xnu-7195.101.1.tar.gz

[apple/xnu.git] / bsd / kern / kern_sig.c

diff --git a/bsd/kern/kern_sig.c b/bsd/kern/kern_sig.c
index 9605be839e6b7814c1a1eafa32b32be73e6cb924..74ecaf33814a9b23939dc2c5f31db2fe04b8ed97 100644 (file)
--- a/bsd/kern/kern_sig.c
+++ b/bsd/kern/kern_sig.c
@@ -1,8 +1,8 @@
 /*
 /*

- * Copyright (c) 1995-2007 Apple Inc. All rights reserved.
+ * Copyright (c) 1995-2016 Apple Inc. All rights reserved.

  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

- * 
+ *

  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in


@@ -11,10 +11,10 @@
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.

- * 
+ *

  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.

- * 
+ *

  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,


@@ -22,7 +22,7 @@
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.

- * 
+ *

  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*


@@ -71,7 +71,7 @@
  * Version 2.0.
  */
 
  * Version 2.0.
  */
 

-#define        SIGPROP         /* include signal properties table */
+#define SIGPROP         /* include signal properties table */

 #include <sys/param.h>
 #include <sys/resourcevar.h>
 #include <sys/proc_internal.h>
 #include <sys/param.h>
 #include <sys/resourcevar.h>
 #include <sys/proc_internal.h>


@@ -88,30 +88,38 @@
 #include <sys/stat.h>
 #include <sys/lock.h>
 #include <sys/kdebug.h>
 #include <sys/stat.h>
 #include <sys/lock.h>
 #include <sys/kdebug.h>

+#include <sys/reason.h>

 
 #include <sys/mount.h>
 #include <sys/sysproto.h>
 
 #include <security/audit/audit.h>
 
 
 #include <sys/mount.h>
 #include <sys/sysproto.h>
 
 #include <security/audit/audit.h>
 

-#include <machine/spl.h>
-

 #include <kern/cpu_number.h>
 
 #include <sys/vm.h>
 #include <kern/cpu_number.h>
 
 #include <sys/vm.h>

-#include <sys/user.h>          /* for coredump */
-#include <kern/ast.h>          /* for APC support */
-#include <kern/lock.h>
-#include <kern/task.h>         /* extern void   *get_bsdtask_info(task_t); */
+#include <sys/user.h>           /* for coredump */
+#include <kern/ast.h>           /* for APC support */
+#include <kern/kalloc.h>
+#include <kern/task.h>          /* extern void   *get_bsdtask_info(task_t); */

 #include <kern/thread.h>
 #include <kern/sched_prim.h>
 #include <kern/thread_call.h>
 #include <kern/thread.h>
 #include <kern/sched_prim.h>
 #include <kern/thread_call.h>

+#include <kern/policy_internal.h>
+

 #include <mach/exception.h>
 #include <mach/task.h>
 #include <mach/thread_act.h>
 #include <libkern/OSAtomic.h>
 
 #include <sys/sdt.h>
 #include <mach/exception.h>
 #include <mach/task.h>
 #include <mach/thread_act.h>
 #include <libkern/OSAtomic.h>
 
 #include <sys/sdt.h>

+#include <sys/codesign.h>
+#include <sys/random.h>
+#include <libkern/section_keywords.h>
+
+#if CONFIG_MACF
+#include <security/mac_framework.h>
+#endif

 
 /*
  * Missing prototypes that Mach should export
 
 /*
  * Missing prototypes that Mach should export


@@ -119,26 +127,26 @@
  * +++
  */
 extern int thread_enable_fpe(thread_t act, int onoff);
  * +++
  */
 extern int thread_enable_fpe(thread_t act, int onoff);

-extern thread_t        port_name_to_thread(mach_port_name_t port_name);
-extern kern_return_t get_signalact(task_t , thread_t *, int);
+extern kern_return_t get_signalact(task_t, thread_t *, int);

 extern unsigned int get_useraddr(void);
 extern unsigned int get_useraddr(void);

-extern kern_return_t task_suspend_internal(task_t);
-extern kern_return_t task_resume_internal(task_t);
+extern boolean_t task_did_exec(task_t task);
+extern boolean_t task_is_exec_copy(task_t task);
+extern void vm_shared_region_reslide_stale(void);

 
 /*
  * ---
  */
 
 
 /*
  * ---
  */
 

-extern void doexception(int exc, mach_exception_code_t code, 
-               mach_exception_subcode_t sub);
+extern void doexception(int exc, mach_exception_code_t code,
+    mach_exception_subcode_t sub);

 
 static void stop(proc_t, proc_t);
 
 static void stop(proc_t, proc_t);

-int cansignal(proc_t, kauth_cred_t, proc_t, int, int);
+static int cansignal_nomac(proc_t, kauth_cred_t, proc_t, int);
+int cansignal(proc_t, kauth_cred_t, proc_t, int);

 int killpg1(proc_t, int, int, int, int);
 int killpg1(proc_t, int, int, int, int);

-int setsigvec(proc_t, thread_t, int, struct __kern_sigaction *, boolean_t in_sigstart);
-static void psignal_uthread(thread_t, int);

 kern_return_t do_bsdexception(int, int, int);
 void __posix_sem_syscall_return(kern_return_t);
 kern_return_t do_bsdexception(int, int, int);
 void __posix_sem_syscall_return(kern_return_t);

+char *proc_name_address(void *p);

 
 /* implementations in osfmk/kern/sync_sema.c. We do not want port.h in this scope, so void * them  */
 kern_return_t semaphore_timedwait_signal_trap_internal(mach_port_name_t, mach_port_name_t, unsigned int, clock_res_t, void (*)(kern_return_t));
 
 /* implementations in osfmk/kern/sync_sema.c. We do not want port.h in this scope, so void * them  */
 kern_return_t semaphore_timedwait_signal_trap_internal(mach_port_name_t, mach_port_name_t, unsigned int, clock_res_t, void (*)(kern_return_t));


@@ -146,34 +154,34 @@ kern_return_t semaphore_timedwait_trap_internal(mach_port_name_t, unsigned int,
 kern_return_t semaphore_wait_signal_trap_internal(mach_port_name_t, mach_port_name_t, void (*)(kern_return_t));
 kern_return_t semaphore_wait_trap_internal(mach_port_name_t, void (*)(kern_return_t));
 
 kern_return_t semaphore_wait_signal_trap_internal(mach_port_name_t, mach_port_name_t, void (*)(kern_return_t));
 kern_return_t semaphore_wait_trap_internal(mach_port_name_t, void (*)(kern_return_t));
 

-static int     filt_sigattach(struct knote *kn);
-static void    filt_sigdetach(struct knote *kn);
-static int     filt_signal(struct knote *kn, long hint);
-static void    filt_signaltouch(struct knote *kn, struct kevent64_s *kev, 
-               long type);
-
-struct filterops sig_filtops = {
-        .f_attach = filt_sigattach,
-        .f_detach = filt_sigdetach,
-        .f_event = filt_signal,
-        .f_touch = filt_signaltouch,
+static int      filt_sigattach(struct knote *kn, struct kevent_qos_s *kev);
+static void     filt_sigdetach(struct knote *kn);
+static int      filt_signal(struct knote *kn, long hint);
+static int      filt_signaltouch(struct knote *kn, struct kevent_qos_s *kev);
+static int      filt_signalprocess(struct knote *kn, struct kevent_qos_s *kev);
+
+SECURITY_READ_ONLY_EARLY(struct filterops) sig_filtops = {
+       .f_attach = filt_sigattach,
+       .f_detach = filt_sigdetach,
+       .f_event = filt_signal,
+       .f_touch = filt_signaltouch,
+       .f_process = filt_signalprocess,

 };
 
 /* structures  and fns for killpg1 iterartion callback and filters */
 struct killpg1_filtargs {
 };
 
 /* structures  and fns for killpg1 iterartion callback and filters */
 struct killpg1_filtargs {

-       int  posix;
-       proc_t cp;
+       bool posix;
+       proc_t curproc;

 };
 
 struct killpg1_iterargs {
 };
 
 struct killpg1_iterargs {

-       proc_t cp;
+       proc_t curproc;

        kauth_cred_t uc;
        int signum;
        kauth_cred_t uc;
        int signum;

-       int * nfoundp;
-       int zombie;
+       int nfound;

 };
 
 };
 

-static int killpg1_filt(proc_t p, void * arg);
+static int killpg1_allfilt(proc_t p, void * arg);

 static int killpg1_pgrpfilt(proc_t p, __unused void * arg);
 static int killpg1_callback(proc_t p, void * arg);
 
 static int killpg1_pgrpfilt(proc_t p, __unused void * arg);
 static int killpg1_callback(proc_t p, void * arg);
 


@@ -186,9 +194,10 @@ static kern_return_t get_signalthread(proc_t, int, thread_t *);
 #define PSIG_LOCKED     0x1
 #define PSIG_VFORK      0x2
 #define PSIG_THREAD     0x4
 #define PSIG_LOCKED     0x1
 #define PSIG_VFORK      0x2
 #define PSIG_THREAD     0x4

+#define PSIG_TRY_THREAD 0x8

 
 

-
-static void psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum);
+static os_reason_t build_signal_reason(int signum, const char *procname);
+static void psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum, os_reason_t signal_reason);

 
 /*
  * NOTE: Source and target may *NOT* overlap! (target is smaller)
 
 /*
  * NOTE: Source and target may *NOT* overlap! (target is smaller)


@@ -196,17 +205,17 @@ static void psignal_internal(proc_t p, task_t task, thread_t thread, int flavor,
 static void
 sigaltstack_kern_to_user32(struct kern_sigaltstack *in, struct user32_sigaltstack *out)
 {
 static void
 sigaltstack_kern_to_user32(struct kern_sigaltstack *in, struct user32_sigaltstack *out)
 {

-       out->ss_sp          = CAST_DOWN_EXPLICIT(user32_addr_t, in->ss_sp);
-       out->ss_size    = CAST_DOWN_EXPLICIT(user32_size_t, in->ss_size);
-       out->ss_flags   = in->ss_flags;
+       out->ss_sp          = CAST_DOWN_EXPLICIT(user32_addr_t, in->ss_sp);
+       out->ss_size    = CAST_DOWN_EXPLICIT(user32_size_t, in->ss_size);
+       out->ss_flags   = in->ss_flags;

 }
 
 static void
 sigaltstack_kern_to_user64(struct kern_sigaltstack *in, struct user64_sigaltstack *out)
 {
 }
 
 static void
 sigaltstack_kern_to_user64(struct kern_sigaltstack *in, struct user64_sigaltstack *out)
 {

-       out->ss_sp          = in->ss_sp;
-       out->ss_size    = in->ss_size;
-       out->ss_flags   = in->ss_flags;
+       out->ss_sp          = in->ss_sp;
+       out->ss_size    = in->ss_size;
+       out->ss_flags   = in->ss_flags;

 }
 
 /*
 }
 
 /*


@@ -217,23 +226,23 @@ sigaltstack_kern_to_user64(struct kern_sigaltstack *in, struct user64_sigaltstac
 static void
 sigaltstack_user32_to_kern(struct user32_sigaltstack *in, struct kern_sigaltstack *out)
 {
 static void
 sigaltstack_user32_to_kern(struct user32_sigaltstack *in, struct kern_sigaltstack *out)
 {

-       out->ss_flags   = in->ss_flags;
-       out->ss_size    = in->ss_size;
-       out->ss_sp              = CAST_USER_ADDR_T(in->ss_sp);
+       out->ss_flags   = in->ss_flags;
+       out->ss_size    = in->ss_size;
+       out->ss_sp              = CAST_USER_ADDR_T(in->ss_sp);

 }
 static void
 sigaltstack_user64_to_kern(struct user64_sigaltstack *in, struct kern_sigaltstack *out)
 {
 }
 static void
 sigaltstack_user64_to_kern(struct user64_sigaltstack *in, struct kern_sigaltstack *out)
 {

-       out->ss_flags   = in->ss_flags;
-       out->ss_size    = in->ss_size;
-       out->ss_sp              = in->ss_sp;
+       out->ss_flags   = in->ss_flags;
+       out->ss_size    = (user_size_t)in->ss_size;
+       out->ss_sp      = (user_addr_t)in->ss_sp;

 }
 
 static void
 sigaction_kern_to_user32(struct kern_sigaction *in, struct user32_sigaction *out)
 {
        /* This assumes 32 bit __sa_handler is of type sig_t */
 }
 
 static void
 sigaction_kern_to_user32(struct kern_sigaction *in, struct user32_sigaction *out)
 {
        /* This assumes 32 bit __sa_handler is of type sig_t */

-       out->__sigaction_u.__sa_handler = CAST_DOWN_EXPLICIT(user32_addr_t,in->__sigaction_u.__sa_handler);
+       out->__sigaction_u.__sa_handler = CAST_DOWN_EXPLICIT(user32_addr_t, in->__sigaction_u.__sa_handler);

        out->sa_mask = in->sa_mask;
        out->sa_flags = in->sa_flags;
 }
        out->sa_mask = in->sa_mask;
        out->sa_flags = in->sa_flags;
 }


@@ -253,26 +262,35 @@ __sigaction_user32_to_kern(struct __user32_sigaction *in, struct __kern_sigactio
        out->sa_tramp = CAST_USER_ADDR_T(in->sa_tramp);
        out->sa_mask = in->sa_mask;
        out->sa_flags = in->sa_flags;
        out->sa_tramp = CAST_USER_ADDR_T(in->sa_tramp);
        out->sa_mask = in->sa_mask;
        out->sa_flags = in->sa_flags;

+
+       kern_return_t kr;
+       kr = machine_thread_function_pointers_convert_from_user(current_thread(),
+           &out->sa_tramp, 1);
+       assert(kr == KERN_SUCCESS);

 }
 
 static void
 __sigaction_user64_to_kern(struct __user64_sigaction *in, struct __kern_sigaction *out)
 {
 }
 
 static void
 __sigaction_user64_to_kern(struct __user64_sigaction *in, struct __kern_sigaction *out)
 {

-       out->__sigaction_u.__sa_handler = in->__sigaction_u.__sa_handler;
-       out->sa_tramp = in->sa_tramp;
+       out->__sigaction_u.__sa_handler = (user_addr_t)in->__sigaction_u.__sa_handler;
+       out->sa_tramp = (user_addr_t)in->sa_tramp;

        out->sa_mask = in->sa_mask;
        out->sa_flags = in->sa_flags;
        out->sa_mask = in->sa_mask;
        out->sa_flags = in->sa_flags;

+
+       kern_return_t kr;
+       kr = machine_thread_function_pointers_convert_from_user(current_thread(),
+           &out->sa_tramp, 1);
+       assert(kr == KERN_SUCCESS);

 }
 
 #if SIGNAL_DEBUG
 void ram_printf(int);
 }
 
 #if SIGNAL_DEBUG
 void ram_printf(int);

-int ram_debug=0;
-unsigned int rdebug_proc=0;
+int ram_debug = 0;
+unsigned int rdebug_proc = 0;

 void
 ram_printf(int x)
 {
 void
 ram_printf(int x)
 {

-    printf("x is %d",x);
-
+       printf("x is %d", x);

 }
 #endif /* SIGNAL_DEBUG */
 
 }
 #endif /* SIGNAL_DEBUG */
 


@@ -283,73 +301,136 @@ signal_setast(thread_t sig_actthread)
        act_set_astbsd(sig_actthread);
 }
 
        act_set_astbsd(sig_actthread);
 }
 

-/*
- * Can process p, with ucred uc, send the signal signum to process q?
- * uc is refcounted  by the caller so internal fileds can be used safely
- * when called with zombie arg, list lock is held
- */
-int
-cansignal(proc_t p, kauth_cred_t uc, proc_t q, int signum, int zombie)
+static int
+cansignal_nomac(proc_t src, kauth_cred_t uc_src, proc_t dst, int signum)

 {
 {

-       kauth_cred_t my_cred;
-       struct session * p_sessp = SESSION_NULL;
-       struct session * q_sessp = SESSION_NULL;
-#if CONFIG_MACF
-       int error;
+       /* you can signal yourself */
+       if (src == dst) {
+               return 1;
+       }

 
 

-       error = mac_proc_check_signal(p, q, signum);
-       if (error)
-               return (0);
-#endif
+       /* you can't send the init proc SIGKILL, even if root */
+       if (signum == SIGKILL && dst == initproc) {
+               return 0;
+       }

 
 

-       /* you can signal yourself */
-       if (p == q)
-               return(1);
+       /* otherwise, root can always signal */
+       if (kauth_cred_issuser(uc_src)) {
+               return 1;
+       }

 
 

-       if (!suser(uc, NULL))
-               return (1);             /* root can always signal */
+       /* processes in the same session can send SIGCONT to each other */
+       {
+               struct session *sess_src = SESSION_NULL;
+               struct session *sess_dst = SESSION_NULL;

 
 

-       if (zombie == 0)
+               /* The session field is protected by the list lock. */

                proc_list_lock();
                proc_list_lock();

-       if (p->p_pgrp != PGRP_NULL)
-               p_sessp = p->p_pgrp->pg_session;
-       if (q->p_pgrp != PGRP_NULL)
-               q_sessp = q->p_pgrp->pg_session;
+               if (src->p_pgrp != PGRP_NULL) {
+                       sess_src = src->p_pgrp->pg_session;
+               }
+               if (dst->p_pgrp != PGRP_NULL) {
+                       sess_dst = dst->p_pgrp->pg_session;
+               }
+               proc_list_unlock();

 
 

-       if (signum == SIGCONT && q_sessp == p_sessp) {
-               if (zombie == 0)
-                       proc_list_unlock();
-               return (1);             /* SIGCONT in session */
+               /* allow SIGCONT within session and for processes without session */
+               if (signum == SIGCONT && sess_src == sess_dst) {
+                       return 1;
+               }

        }
 
        }
 

-       if (zombie == 0) 
-               proc_list_unlock();
+       /* the source process must be authorized to signal the target */
+       {
+               int allowed = 0;
+               kauth_cred_t uc_dst = NOCRED, uc_ref = NOCRED;

 
 

-       /*
-        * If the real or effective UID of the sender matches the real
-        * or saved UID of the target, permit the signal to
-        * be sent.
-        */
-       if (zombie == 0)
-               my_cred = kauth_cred_proc_ref(q);
-       else
-               my_cred = proc_ucred(q);
+               uc_dst = uc_ref = kauth_cred_proc_ref(dst);
+
+               /*
+                * If the real or effective UID of the sender matches the real or saved
+                * UID of the target, allow the signal to be sent.
+                */
+               if (kauth_cred_getruid(uc_src) == kauth_cred_getruid(uc_dst) ||
+                   kauth_cred_getruid(uc_src) == kauth_cred_getsvuid(uc_dst) ||
+                   kauth_cred_getuid(uc_src) == kauth_cred_getruid(uc_dst) ||
+                   kauth_cred_getuid(uc_src) == kauth_cred_getsvuid(uc_dst)) {
+                       allowed = 1;
+               }

 
 

-       if (kauth_cred_getruid(uc) == kauth_cred_getruid(my_cred) ||
-           kauth_cred_getruid(uc) == kauth_cred_getsvuid(my_cred) ||
-           kauth_cred_getuid(uc) == kauth_cred_getruid(my_cred) ||
-           kauth_cred_getuid(uc) == kauth_cred_getsvuid(my_cred)) {
-               if (zombie == 0)
-                       kauth_cred_unref(&my_cred);
-               return (1);
+               if (uc_ref != NOCRED) {
+                       kauth_cred_unref(&uc_ref);
+                       uc_ref = NOCRED;
+               }
+
+               return allowed;
+       }
+}
+
+/*
+ * Can process `src`, with ucred `uc_src`, send the signal `signum` to process
+ * `dst`?  The ucred is referenced by the caller so internal fileds can be used
+ * safely.
+ */
+int
+cansignal(proc_t src, kauth_cred_t uc_src, proc_t dst, int signum)
+{
+#if CONFIG_MACF
+       if (mac_proc_check_signal(src, dst, signum)) {
+               return 0;

        }
        }

+#endif
+
+       return cansignal_nomac(src, uc_src, dst, signum);
+}

 
 

-       if (zombie == 0)
-               kauth_cred_unref(&my_cred);
+/*
+ * <rdar://problem/21952708> Some signals can be restricted from being handled,
+ * forcing the default action for that signal. This behavior applies only to
+ * non-root (EUID != 0) processes, and is configured with the "sigrestrict=x"
+ * bootarg:
+ *
+ *   0 (default): Disallow use of restricted signals. Trying to register a handler
+ *             returns ENOTSUP, which userspace may use to take special action (e.g. abort).
+ *   1: As above, but return EINVAL. Restricted signals behave similarly to SIGKILL.
+ *   2: Usual POSIX semantics.
+ */
+unsigned sigrestrict_arg = 0;

 
 

-       return (0);
+#if PLATFORM_WatchOS
+static int
+sigrestrictmask(void)
+{
+       if (kauth_getuid() != 0 && sigrestrict_arg != 2) {
+               return SIGRESTRICTMASK;
+       }
+       return 0;

 }
 
 }
 

+static int
+signal_is_restricted(proc_t p, int signum)
+{
+       if (sigmask(signum) & sigrestrictmask()) {
+               if (sigrestrict_arg == 0 &&
+                   task_get_apptype(p->task) == TASK_APPTYPE_APP_DEFAULT) {
+                       return ENOTSUP;
+               } else {
+                       return EINVAL;
+               }
+       }
+       return 0;
+}
+
+#else
+
+static inline int
+signal_is_restricted(proc_t p, int signum)
+{
+       (void)p;
+       (void)signum;
+       return 0;
+}
+#endif /* !PLATFORM_WatchOS */

 
 /*
  * Returns:    0                       Success
 
 /*
  * Returns:    0                       Success


@@ -372,104 +453,136 @@ sigaction(proc_t p, struct sigaction_args *uap, __unused int32_t *retval)
        struct sigacts *ps = p->p_sigacts;
 
        int signum;
        struct sigacts *ps = p->p_sigacts;
 
        int signum;

-       int bit, error=0;
+       int bit, error = 0;
+       uint32_t sigreturn_validation = PS_SIGRETURN_VALIDATION_DEFAULT;

 
        signum = uap->signum;
        if (signum <= 0 || signum >= NSIG ||
 
        signum = uap->signum;
        if (signum <= 0 || signum >= NSIG ||

-           signum == SIGKILL || signum == SIGSTOP)
-               return (EINVAL);
+           signum == SIGKILL || signum == SIGSTOP) {
+               return EINVAL;
+       }
+
+       if (uap->nsa) {
+               if (IS_64BIT_PROCESS(p)) {
+                       struct __user64_sigaction       __vec64;
+                       error = copyin(uap->nsa, &__vec64, sizeof(__vec64));
+                       __sigaction_user64_to_kern(&__vec64, &__vec);
+               } else {
+                       struct __user32_sigaction       __vec32;
+                       error = copyin(uap->nsa, &__vec32, sizeof(__vec32));
+                       __sigaction_user32_to_kern(&__vec32, &__vec);
+               }
+               if (error) {
+                       return error;
+               }
+
+               sigreturn_validation = (__vec.sa_flags & SA_VALIDATE_SIGRETURN_FROM_SIGTRAMP) ?
+                   PS_SIGRETURN_VALIDATION_ENABLED : PS_SIGRETURN_VALIDATION_DISABLED;
+               __vec.sa_flags &= SA_USERSPACE_MASK; /* Only pass on valid sa_flags */
+
+               if ((__vec.sa_flags & SA_SIGINFO) || __vec.sa_handler != SIG_DFL) {
+                       if ((error = signal_is_restricted(p, signum))) {
+                               if (error == ENOTSUP) {
+                                       printf("%s(%d): denied attempt to register action for signal %d\n",
+                                           proc_name_address(p), proc_pid(p), signum);
+                               }
+                               return error;
+                       }
+               }
+       }

 
        if (uap->osa) {
                sa->sa_handler = ps->ps_sigact[signum];
                sa->sa_mask = ps->ps_catchmask[signum];
                bit = sigmask(signum);
                sa->sa_flags = 0;
 
        if (uap->osa) {
                sa->sa_handler = ps->ps_sigact[signum];
                sa->sa_mask = ps->ps_catchmask[signum];
                bit = sigmask(signum);
                sa->sa_flags = 0;

-               if ((ps->ps_sigonstack & bit) != 0)
+               if ((ps->ps_sigonstack & bit) != 0) {

                        sa->sa_flags |= SA_ONSTACK;
                        sa->sa_flags |= SA_ONSTACK;

-               if ((ps->ps_sigintr & bit) == 0)
+               }
+               if ((ps->ps_sigintr & bit) == 0) {

                        sa->sa_flags |= SA_RESTART;
                        sa->sa_flags |= SA_RESTART;

-               if (ps->ps_siginfo & bit)
+               }
+               if (ps->ps_siginfo & bit) {

                        sa->sa_flags |= SA_SIGINFO;
                        sa->sa_flags |= SA_SIGINFO;

-               if (ps->ps_signodefer & bit)
+               }
+               if (ps->ps_signodefer & bit) {

                        sa->sa_flags |= SA_NODEFER;
                        sa->sa_flags |= SA_NODEFER;

-               if (ps->ps_64regset & bit)
-                       sa->sa_flags |= SA_64REGSET;
-               if ((signum == SIGCHLD) && (p->p_flag & P_NOCLDSTOP))
+               }
+               if ((signum == SIGCHLD) && (p->p_flag & P_NOCLDSTOP)) {

                        sa->sa_flags |= SA_NOCLDSTOP;
                        sa->sa_flags |= SA_NOCLDSTOP;

-               if ((signum == SIGCHLD) && (p->p_flag & P_NOCLDWAIT))
+               }
+               if ((signum == SIGCHLD) && (p->p_flag & P_NOCLDWAIT)) {

                        sa->sa_flags |= SA_NOCLDWAIT;
                        sa->sa_flags |= SA_NOCLDWAIT;

+               }

 
                if (IS_64BIT_PROCESS(p)) {
 
                if (IS_64BIT_PROCESS(p)) {

-                       struct user64_sigaction vec64;
-                       
+                       struct user64_sigaction vec64 = {};

                        sigaction_kern_to_user64(sa, &vec64);
                        error = copyout(&vec64, uap->osa, sizeof(vec64));
                } else {
                        sigaction_kern_to_user64(sa, &vec64);
                        error = copyout(&vec64, uap->osa, sizeof(vec64));
                } else {

-                       struct user32_sigaction vec32;
-                       
+                       struct user32_sigaction vec32 = {};

                        sigaction_kern_to_user32(sa, &vec32);
                        error = copyout(&vec32, uap->osa, sizeof(vec32));
                }
                        sigaction_kern_to_user32(sa, &vec32);
                        error = copyout(&vec32, uap->osa, sizeof(vec32));
                }

-               if (error)
-                       return (error);
+               if (error) {
+                       return error;
+               }

        }
        }

+

        if (uap->nsa) {
        if (uap->nsa) {

-               if (IS_64BIT_PROCESS(p)) {
-                       struct __user64_sigaction       __vec64;
-                       
-                       error = copyin(uap->nsa, &__vec64, sizeof(__vec64));
-                       __sigaction_user64_to_kern(&__vec64, &__vec);
-               } else {
-                       struct __user32_sigaction       __vec32;
-                       
-                       error = copyin(uap->nsa, &__vec32, sizeof(__vec32));
-                       __sigaction_user32_to_kern(&__vec32, &__vec);
+               uint32_t old_sigreturn_validation = atomic_load_explicit(
+                       &ps->ps_sigreturn_validation, memory_order_relaxed);
+               if (old_sigreturn_validation == PS_SIGRETURN_VALIDATION_DEFAULT) {
+                       atomic_compare_exchange_strong_explicit(&ps->ps_sigreturn_validation,
+                           &old_sigreturn_validation, sigreturn_validation,
+                           memory_order_relaxed, memory_order_relaxed);

                }
                }

-               if (error)
-                       return (error);
-               __vec.sa_flags &= SA_USERSPACE_MASK; /* Only pass on valid sa_flags */

                error = setsigvec(p, current_thread(), signum, &__vec, FALSE);
        }
                error = setsigvec(p, current_thread(), signum, &__vec, FALSE);
        }

-       return (error);
+
+       return error;

 }
 
 /* Routines to manipulate bits on all threads */
 int
 }
 
 /* Routines to manipulate bits on all threads */
 int

-clear_procsiglist(proc_t p,  int bit, boolean_t in_signalstart)
+clear_procsiglist(proc_t p, int bit, boolean_t in_signalstart)

 {
        struct uthread * uth;
        thread_t thact;
 
        proc_lock(p);
 {
        struct uthread * uth;
        thread_t thact;
 
        proc_lock(p);

-       if (!in_signalstart)
+       if (!in_signalstart) {

                proc_signalstart(p, 1);
                proc_signalstart(p, 1);

+       }

 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {

-               thact = p->p_vforkact;  
+               thact = p->p_vforkact;

                uth = (struct uthread *)get_bsdthread_info(thact);
                if (uth) {
                        uth->uu_siglist &= ~bit;
                }
                uth = (struct uthread *)get_bsdthread_info(thact);
                if (uth) {
                        uth->uu_siglist &= ~bit;
                }

-               if (!in_signalstart)
+               if (!in_signalstart) {

                        proc_signalend(p, 1);
                        proc_signalend(p, 1);

+               }

                proc_unlock(p);
                proc_unlock(p);

-               return(0);
-       } 
+               return 0;
+       }

 
        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
                uth->uu_siglist &= ~bit;
        }
        p->p_siglist &= ~bit;
 
        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
                uth->uu_siglist &= ~bit;
        }
        p->p_siglist &= ~bit;

-       if (!in_signalstart)
+       if (!in_signalstart) {

                proc_signalend(p, 1);
                proc_signalend(p, 1);

+       }

        proc_unlock(p);
 
        proc_unlock(p);
 

-       return(0);
+       return 0;

 }
 
 
 static int
 }
 
 
 static int

-unblock_procsigmask(proc_t p,  int bit)
+unblock_procsigmask(proc_t p, int bit)

 {
        struct uthread * uth;
        thread_t thact;
 {
        struct uthread * uth;
        thread_t thact;


@@ -478,7 +591,7 @@ unblock_procsigmask(proc_t p,  int bit)
        proc_signalstart(p, 1);
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
        proc_signalstart(p, 1);
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {

-               thact = p->p_vforkact;  
+               thact = p->p_vforkact;

                uth = (struct uthread *)get_bsdthread_info(thact);
                if (uth) {
                        uth->uu_sigmask &= ~bit;
                uth = (struct uthread *)get_bsdthread_info(thact);
                if (uth) {
                        uth->uu_sigmask &= ~bit;


@@ -486,8 +599,8 @@ unblock_procsigmask(proc_t p,  int bit)
                p->p_sigmask &= ~bit;
                proc_signalend(p, 1);
                proc_unlock(p);
                p->p_sigmask &= ~bit;
                proc_signalend(p, 1);
                proc_unlock(p);

-               return(0);
-       } 
+               return 0;
+       }

        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
                uth->uu_sigmask &= ~bit;
        }
        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
                uth->uu_sigmask &= ~bit;
        }


@@ -495,11 +608,11 @@ unblock_procsigmask(proc_t p,  int bit)
 
        proc_signalend(p, 1);
        proc_unlock(p);
 
        proc_signalend(p, 1);
        proc_unlock(p);

-       return(0);
+       return 0;

 }
 
 static int
 }
 
 static int

-block_procsigmask(proc_t p,  int bit)
+block_procsigmask(proc_t p, int bit)

 {
        struct uthread * uth;
        thread_t thact;
 {
        struct uthread * uth;
        thread_t thact;


@@ -508,7 +621,7 @@ block_procsigmask(proc_t p,  int bit)
        proc_signalstart(p, 1);
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
        proc_signalstart(p, 1);
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {

-               thact = p->p_vforkact;  
+               thact = p->p_vforkact;

                uth = (struct uthread *)get_bsdthread_info(thact);
                if (uth) {
                        uth->uu_sigmask |= bit;
                uth = (struct uthread *)get_bsdthread_info(thact);
                if (uth) {
                        uth->uu_sigmask |= bit;


@@ -516,8 +629,8 @@ block_procsigmask(proc_t p,  int bit)
                p->p_sigmask |=  bit;
                proc_signalend(p, 1);
                proc_unlock(p);
                p->p_sigmask |=  bit;
                proc_signalend(p, 1);
                proc_unlock(p);

-               return(0);
-       } 
+               return 0;
+       }

        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
                uth->uu_sigmask |= bit;
        }
        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
                uth->uu_sigmask |= bit;
        }


@@ -525,11 +638,11 @@ block_procsigmask(proc_t p,  int bit)
 
        proc_signalend(p, 1);
        proc_unlock(p);
 
        proc_signalend(p, 1);
        proc_unlock(p);

-       return(0);
+       return 0;

 }
 
 int
 }
 
 int

-set_procsigmask(proc_t p,  int bit)
+set_procsigmask(proc_t p, int bit)

 {
        struct uthread * uth;
        thread_t thact;
 {
        struct uthread * uth;
        thread_t thact;


@@ -538,7 +651,7 @@ set_procsigmask(proc_t p,  int bit)
        proc_signalstart(p, 1);
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
        proc_signalstart(p, 1);
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {

-               thact = p->p_vforkact;  
+               thact = p->p_vforkact;

                uth = (struct uthread *)get_bsdthread_info(thact);
                if (uth) {
                        uth->uu_sigmask = bit;
                uth = (struct uthread *)get_bsdthread_info(thact);
                if (uth) {
                        uth->uu_sigmask = bit;


@@ -546,8 +659,8 @@ set_procsigmask(proc_t p,  int bit)
                p->p_sigmask =  bit;
                proc_signalend(p, 1);
                proc_unlock(p);
                p->p_sigmask =  bit;
                proc_signalend(p, 1);
                proc_unlock(p);

-               return(0);
-       } 
+               return 0;
+       }

        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
                uth->uu_sigmask = bit;
        }
        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
                uth->uu_sigmask = bit;
        }


@@ -555,7 +668,7 @@ set_procsigmask(proc_t p,  int bit)
        proc_signalend(p, 1);
        proc_unlock(p);
 
        proc_signalend(p, 1);
        proc_unlock(p);
 

-       return(0);
+       return 0;

 }
 
 /* XXX should be static? */
 }
 
 /* XXX should be static? */


@@ -575,53 +688,55 @@ setsigvec(proc_t p, __unused thread_t thread, int signum, struct __kern_sigactio
        struct sigacts *ps = p->p_sigacts;
        int bit;
 
        struct sigacts *ps = p->p_sigacts;
        int bit;
 

+       assert(signum < NSIG);
+

        if ((signum == SIGKILL || signum == SIGSTOP) &&
        if ((signum == SIGKILL || signum == SIGSTOP) &&

-               sa->sa_handler != SIG_DFL)
-               return(EINVAL);
+           sa->sa_handler != SIG_DFL) {
+               return EINVAL;
+       }

        bit = sigmask(signum);
        /*
         * Change setting atomically.
         */
        ps->ps_sigact[signum] = sa->sa_handler;
        ps->ps_trampact[signum] = sa->sa_tramp;
        bit = sigmask(signum);
        /*
         * Change setting atomically.
         */
        ps->ps_sigact[signum] = sa->sa_handler;
        ps->ps_trampact[signum] = sa->sa_tramp;

-       ps->ps_catchmask[signum] = sa->sa_mask &~ sigcantmask;
-       if (sa->sa_flags & SA_SIGINFO)
+       ps->ps_catchmask[signum] = sa->sa_mask & ~sigcantmask;
+       if (sa->sa_flags & SA_SIGINFO) {

                ps->ps_siginfo |= bit;
                ps->ps_siginfo |= bit;

-       else
+       } else {

                ps->ps_siginfo &= ~bit;
                ps->ps_siginfo &= ~bit;

-       if (sa->sa_flags & SA_64REGSET)
-               ps->ps_64regset |= bit;
-       else
-               ps->ps_64regset &= ~bit;
-       if ((sa->sa_flags & SA_RESTART) == 0)
+       }
+       if ((sa->sa_flags & SA_RESTART) == 0) {

                ps->ps_sigintr |= bit;
                ps->ps_sigintr |= bit;

-       else
+       } else {

                ps->ps_sigintr &= ~bit;
                ps->ps_sigintr &= ~bit;

-       if (sa->sa_flags & SA_ONSTACK)
+       }
+       if (sa->sa_flags & SA_ONSTACK) {

                ps->ps_sigonstack |= bit;
                ps->ps_sigonstack |= bit;

-       else
+       } else {

                ps->ps_sigonstack &= ~bit;
                ps->ps_sigonstack &= ~bit;

-       if (sa->sa_flags & SA_USERTRAMP)
-               ps->ps_usertramp |= bit;
-       else
-               ps->ps_usertramp &= ~bit;
-       if (sa->sa_flags & SA_RESETHAND)
+       }
+       if (sa->sa_flags & SA_RESETHAND) {

                ps->ps_sigreset |= bit;
                ps->ps_sigreset |= bit;

-       else
+       } else {

                ps->ps_sigreset &= ~bit;
                ps->ps_sigreset &= ~bit;

-       if (sa->sa_flags & SA_NODEFER)
+       }
+       if (sa->sa_flags & SA_NODEFER) {

                ps->ps_signodefer |= bit;
                ps->ps_signodefer |= bit;

-       else
+       } else {

                ps->ps_signodefer &= ~bit;
                ps->ps_signodefer &= ~bit;

+       }

        if (signum == SIGCHLD) {
        if (signum == SIGCHLD) {

-               if (sa->sa_flags & SA_NOCLDSTOP)
+               if (sa->sa_flags & SA_NOCLDSTOP) {

                        OSBitOrAtomic(P_NOCLDSTOP, &p->p_flag);
                        OSBitOrAtomic(P_NOCLDSTOP, &p->p_flag);

-               else
+               } else {

                        OSBitAndAtomic(~((uint32_t)P_NOCLDSTOP), &p->p_flag);
                        OSBitAndAtomic(~((uint32_t)P_NOCLDSTOP), &p->p_flag);

-               if ((sa->sa_flags & SA_NOCLDWAIT) || (sa->sa_handler == SIG_IGN))
+               }
+               if ((sa->sa_flags & SA_NOCLDWAIT) || (sa->sa_handler == SIG_IGN)) {

                        OSBitOrAtomic(P_NOCLDWAIT, &p->p_flag);
                        OSBitOrAtomic(P_NOCLDWAIT, &p->p_flag);

-               else
+               } else {

                        OSBitAndAtomic(~((uint32_t)P_NOCLDWAIT), &p->p_flag);
                        OSBitAndAtomic(~((uint32_t)P_NOCLDWAIT), &p->p_flag);

+               }

        }
 
        /*
        }
 
        /*


@@ -632,19 +747,20 @@ setsigvec(proc_t p, __unused thread_t thread, int signum, struct __kern_sigactio
         */
        if (sa->sa_handler == SIG_IGN ||
            (sigprop[signum] & SA_IGNORE && sa->sa_handler == SIG_DFL)) {
         */
        if (sa->sa_handler == SIG_IGN ||
            (sigprop[signum] & SA_IGNORE && sa->sa_handler == SIG_DFL)) {

-

                clear_procsiglist(p, bit, in_sigstart);
                clear_procsiglist(p, bit, in_sigstart);

-               if (signum != SIGCONT)
-                       p->p_sigignore |= bit;  /* easier in psignal */
+               if (signum != SIGCONT) {
+                       p->p_sigignore |= bit;  /* easier in psignal */
+               }

                p->p_sigcatch &= ~bit;
        } else {
                p->p_sigignore &= ~bit;
                p->p_sigcatch &= ~bit;
        } else {
                p->p_sigignore &= ~bit;

-               if (sa->sa_handler == SIG_DFL)
+               if (sa->sa_handler == SIG_DFL) {

                        p->p_sigcatch &= ~bit;
                        p->p_sigcatch &= ~bit;

-               else
+               } else {

                        p->p_sigcatch |= bit;
                        p->p_sigcatch |= bit;

+               }

        }
        }

-       return(0);
+       return 0;

 }
 
 /*
 }
 
 /*


@@ -656,9 +772,11 @@ siginit(proc_t p)
 {
        int i;
 
 {
        int i;
 

-       for (i = 1; i < NSIG; i++)
-               if (sigprop[i] & SA_IGNORE && i != SIGCONT)
+       for (i = 1; i < NSIG; i++) {
+               if (sigprop[i] & SA_IGNORE && i != SIGCONT) {

                        p->p_sigignore |= sigmask(i);
                        p->p_sigignore |= sigmask(i);

+               }
+       }

 }
 
 /*
 }
 
 /*


@@ -691,17 +809,23 @@ execsigs(proc_t p, thread_t thread)
         * and are now ignored by default).
         */
        while (p->p_sigcatch) {
         * and are now ignored by default).
         */
        while (p->p_sigcatch) {

-               nc = ffs((long)p->p_sigcatch);
+               nc = ffs((unsigned int)p->p_sigcatch);

                mask = sigmask(nc);
                p->p_sigcatch &= ~mask;
                if (sigprop[nc] & SA_IGNORE) {
                mask = sigmask(nc);
                p->p_sigcatch &= ~mask;
                if (sigprop[nc] & SA_IGNORE) {

-                       if (nc != SIGCONT)
+                       if (nc != SIGCONT) {

                                p->p_sigignore |= mask;
                                p->p_sigignore |= mask;

+                       }

                        ut->uu_siglist &= ~mask;
                }
                ps->ps_sigact[nc] = SIG_DFL;
        }
 
                        ut->uu_siglist &= ~mask;
                }
                ps->ps_sigact[nc] = SIG_DFL;
        }
 

+       atomic_store_explicit(&ps->ps_sigreturn_validation,
+           PS_SIGRETURN_VALIDATION_DEFAULT, memory_order_relaxed);
+       /* Generate random token value used to validate sigreturn arguments */
+       read_random(&ps->ps_sigreturn_token, sizeof(ps->ps_sigreturn_token));
+

        /*
         * Reset stack state to the user stack.
         * Clear set of signals caught on the signal stack.
        /*
         * Reset stack state to the user stack.
         * Clear set of signals caught on the signal stack.


@@ -737,8 +861,9 @@ sigprocmask(proc_t p, struct sigprocmask_args *uap, __unused int32_t *retval)
                goto out;
        }
        error = copyin(uap->mask, &nmask, sizeof(sigset_t));
                goto out;
        }
        error = copyin(uap->mask, &nmask, sizeof(sigset_t));

-       if (error)
+       if (error) {

                goto out;
                goto out;

+       }

 
        switch (uap->how) {
        case SIG_BLOCK:
 
        switch (uap->how) {
        case SIG_BLOCK:


@@ -755,15 +880,16 @@ sigprocmask(proc_t p, struct sigprocmask_args *uap, __unused int32_t *retval)
                set_procsigmask(p, (nmask & ~sigcantmask));
                signal_setast(current_thread());
                break;
                set_procsigmask(p, (nmask & ~sigcantmask));
                signal_setast(current_thread());
                break;

-       
+

        default:
                error = EINVAL;
                break;
        }
 out:
        default:
                error = EINVAL;
                break;
        }
 out:

-       if (!error && omask != USER_ADDR_NULL)
+       if (!error && omask != USER_ADDR_NULL) {

                copyout(&oldmask, omask, sizeof(sigset_t));
                copyout(&oldmask, omask, sizeof(sigset_t));

-       return (error);
+       }
+       return error;

 }
 
 int
 }
 
 int


@@ -775,9 +901,10 @@ sigpending(__unused proc_t p, struct sigpending_args *uap, __unused int32_t *ret
        ut = (struct uthread *)get_bsdthread_info(current_thread());
        pendlist = ut->uu_siglist;
 
        ut = (struct uthread *)get_bsdthread_info(current_thread());
        pendlist = ut->uu_siglist;
 

-       if (uap->osv)
+       if (uap->osv) {

                copyout(&pendlist, uap->osv, sizeof(sigset_t));
                copyout(&pendlist, uap->osv, sizeof(sigset_t));

-       return(0);
+       }
+       return 0;

 }
 
 /*
 }
 
 /*


@@ -797,7 +924,7 @@ int
 sigsuspend(proc_t p, struct sigsuspend_args *uap, int32_t *retval)
 {
        __pthread_testcancel(1);
 sigsuspend(proc_t p, struct sigsuspend_args *uap, int32_t *retval)
 {
        __pthread_testcancel(1);

-       return(sigsuspend_nocancel(p, (struct sigsuspend_nocancel_args *)uap, retval));
+       return sigsuspend_nocancel(p, (struct sigsuspend_nocancel_args *)uap, retval);

 }
 
 int
 }
 
 int


@@ -817,16 +944,16 @@ sigsuspend_nocancel(proc_t p, struct sigsuspend_nocancel_args *uap, __unused int
        ut->uu_oldmask = ut->uu_sigmask;
        ut->uu_flag |= UT_SAS_OLDMASK;
        ut->uu_sigmask = (uap->mask & ~sigcantmask);
        ut->uu_oldmask = ut->uu_sigmask;
        ut->uu_flag |= UT_SAS_OLDMASK;
        ut->uu_sigmask = (uap->mask & ~sigcantmask);

-       (void) tsleep0((caddr_t) p, PPAUSE|PCATCH, "pause", 0, sigcontinue);
+       (void) tsleep0((caddr_t) p, PPAUSE | PCATCH, "pause", 0, sigcontinue);

        /* always return EINTR rather than ERESTART... */
        /* always return EINTR rather than ERESTART... */

-       return (EINTR);
+       return EINTR;

 }
 
 
 int
 __disable_threadsignal(__unused proc_t p,
 }
 
 
 int
 __disable_threadsignal(__unused proc_t p,

-                      __unused struct __disable_threadsignal_args *uap,
-                      __unused int32_t *retval)
+    __unused struct __disable_threadsignal_args *uap,
+    __unused int32_t *retval)

 {
        struct uthread *uth;
 
 {
        struct uthread *uth;
 


@@ -835,28 +962,27 @@ __disable_threadsignal(__unused proc_t p,
        /* No longer valid to have any signal delivered */
        uth->uu_flag |= (UT_NO_SIGMASK | UT_CANCELDISABLE);
 
        /* No longer valid to have any signal delivered */
        uth->uu_flag |= (UT_NO_SIGMASK | UT_CANCELDISABLE);
 

-       return(0);
-
+       return 0;

 }
 
 void
 __pthread_testcancel(int presyscall)
 {
 }
 
 void
 __pthread_testcancel(int presyscall)
 {

-

        thread_t self = current_thread();
        struct uthread * uthread;
 
        uthread = (struct uthread *)get_bsdthread_info(self);
 
        thread_t self = current_thread();
        struct uthread * uthread;
 
        uthread = (struct uthread *)get_bsdthread_info(self);
 

-       
+

        uthread->uu_flag &= ~UT_NOTCANCELPT;
 
        if ((uthread->uu_flag & (UT_CANCELDISABLE | UT_CANCEL | UT_CANCELED)) == UT_CANCEL) {
        uthread->uu_flag &= ~UT_NOTCANCELPT;
 
        if ((uthread->uu_flag & (UT_CANCELDISABLE | UT_CANCEL | UT_CANCELED)) == UT_CANCEL) {

-               if(presyscall != 0) {
+               if (presyscall != 0) {

                        unix_syscall_return(EINTR);
                        /* NOTREACHED */
                        unix_syscall_return(EINTR);
                        /* NOTREACHED */

-               } else 
+               } else {

                        thread_abort_safely(self);
                        thread_abort_safely(self);

+               }

        }
 }
 
        }
 }
 


@@ -864,39 +990,42 @@ __pthread_testcancel(int presyscall)
 
 int
 __pthread_markcancel(__unused proc_t p,
 
 int
 __pthread_markcancel(__unused proc_t p,

-       struct __pthread_markcancel_args *uap, __unused int32_t *retval)
+    struct __pthread_markcancel_args *uap, __unused int32_t *retval)

 {
        thread_act_t target_act;
        int error = 0;
        struct uthread *uth;
 
 {
        thread_act_t target_act;
        int error = 0;
        struct uthread *uth;
 

-       target_act = (thread_act_t)port_name_to_thread(uap->thread_port);
+       target_act = (thread_act_t)port_name_to_thread(uap->thread_port,
+           PORT_TO_THREAD_IN_CURRENT_TASK);

 
 

-       if (target_act == THR_ACT_NULL)
-               return (ESRCH);
+       if (target_act == THR_ACT_NULL) {
+               return ESRCH;
+       }

 
        uth = (struct uthread *)get_bsdthread_info(target_act);
 
        /* if the thread is in vfork do not cancel */
 
        uth = (struct uthread *)get_bsdthread_info(target_act);
 
        /* if the thread is in vfork do not cancel */

-       if ((uth->uu_flag & (UT_VFORK | UT_CANCEL | UT_CANCELED )) == 0) {
+       if ((uth->uu_flag & (UT_VFORK | UT_CANCEL | UT_CANCELED)) == 0) {

                uth->uu_flag |= (UT_CANCEL | UT_NO_SIGMASK);
                uth->uu_flag |= (UT_CANCEL | UT_NO_SIGMASK);

-               if (((uth->uu_flag & UT_NOTCANCELPT) == 0) 
-                       && ((uth->uu_flag & UT_CANCELDISABLE) == 0))
-                               thread_abort_safely(target_act);
+               if (((uth->uu_flag & UT_NOTCANCELPT) == 0)
+                   && ((uth->uu_flag & UT_CANCELDISABLE) == 0)) {
+                       thread_abort_safely(target_act);
+               }

        }
 
        thread_deallocate(target_act);
        }
 
        thread_deallocate(target_act);

-       return (error);
+       return error;

 }
 
 }
 

-/* if action =0 ; return the cancellation state , 
+/* if action =0 ; return the cancellation state ,

  *      if marked for cancellation, make the thread canceled
  * if action = 1 ; Enable the cancel handling
  * if action = 2; Disable the cancel handling
  */
 int
 __pthread_canceled(__unused proc_t p,
  *      if marked for cancellation, make the thread canceled
  * if action = 1 ; Enable the cancel handling
  * if action = 2; Disable the cancel handling
  */
 int
 __pthread_canceled(__unused proc_t p,

-       struct __pthread_canceled_args *uap, __unused int32_t *retval)
+    struct __pthread_canceled_args *uap, __unused int32_t *retval)

 {
        thread_act_t thread;
        struct uthread *uth;
 {
        thread_act_t thread;
        struct uthread *uth;


@@ -906,38 +1035,40 @@ __pthread_canceled(__unused proc_t p,
        uth = (struct uthread *)get_bsdthread_info(thread);
 
        switch (action) {
        uth = (struct uthread *)get_bsdthread_info(thread);
 
        switch (action) {

-               case 1:
-                       uth->uu_flag &= ~UT_CANCELDISABLE;
-                       return(0);
-               case 2:
-                       uth->uu_flag |= UT_CANCELDISABLE;
-                       return(0);
-               case 0:
-               default:
-                       /* if the thread is in vfork do not cancel */
-                       if((uth->uu_flag & ( UT_CANCELDISABLE | UT_CANCEL | UT_CANCELED)) == UT_CANCEL) {
-                               uth->uu_flag &= ~UT_CANCEL;
-                               uth->uu_flag |= (UT_CANCELED | UT_NO_SIGMASK);
-                               return(0);
-                       }
-                       return(EINVAL);
-       }               
-       return(EINVAL);
+       case 1:
+               uth->uu_flag &= ~UT_CANCELDISABLE;
+               return 0;
+       case 2:
+               uth->uu_flag |= UT_CANCELDISABLE;
+               return 0;
+       case 0:
+       default:
+               /* if the thread is in vfork do not cancel */
+               if ((uth->uu_flag & (UT_CANCELDISABLE | UT_CANCEL | UT_CANCELED)) == UT_CANCEL) {
+                       uth->uu_flag &= ~UT_CANCEL;
+                       uth->uu_flag |= (UT_CANCELED | UT_NO_SIGMASK);
+                       return 0;
+               }
+               return EINVAL;
+       }
+       return EINVAL;

 }
 
 }
 

+__attribute__((noreturn))

 void
 void

-__posix_sem_syscall_return(kern_return_t kern_result) 
+__posix_sem_syscall_return(kern_return_t kern_result)

 {
        int error = 0;
 
 {
        int error = 0;
 

-       if (kern_result == KERN_SUCCESS)
+       if (kern_result == KERN_SUCCESS) {

                error = 0;
                error = 0;

-       else if (kern_result == KERN_ABORTED)
+       } else if (kern_result == KERN_ABORTED) {

                error = EINTR;
                error = EINTR;

-       else if (kern_result == KERN_OPERATION_TIMED_OUT) 
+       } else if (kern_result == KERN_OPERATION_TIMED_OUT) {

                error = ETIMEDOUT;
                error = ETIMEDOUT;

-       else
+       } else {

                error = EINVAL;
                error = EINVAL;

+       }

        unix_syscall_return(error);
        /* does not return */
 }
        unix_syscall_return(error);
        /* does not return */
 }


@@ -952,94 +1083,92 @@ __posix_sem_syscall_return(kern_return_t kern_result)
  */
 int
 __old_semwait_signal(proc_t p, struct __old_semwait_signal_args *uap,
  */
 int
 __old_semwait_signal(proc_t p, struct __old_semwait_signal_args *uap,

-                     int32_t *retval)
+    int32_t *retval)

 {
        __pthread_testcancel(0);
 {
        __pthread_testcancel(0);

-       return(__old_semwait_signal_nocancel(p, (struct __old_semwait_signal_nocancel_args *)uap, retval));
+       return __old_semwait_signal_nocancel(p, (struct __old_semwait_signal_nocancel_args *)uap, retval);

 }
 
 int
 __old_semwait_signal_nocancel(proc_t p, struct __old_semwait_signal_nocancel_args *uap,
 }
 
 int
 __old_semwait_signal_nocancel(proc_t p, struct __old_semwait_signal_nocancel_args *uap,

-                              __unused int32_t *retval)
+    __unused int32_t *retval)

 {
 {

-       

        kern_return_t kern_result;
        int error;
        mach_timespec_t then;
        struct timespec now;
        struct user_timespec ts;
        boolean_t truncated_timeout = FALSE;
        kern_return_t kern_result;
        int error;
        mach_timespec_t then;
        struct timespec now;
        struct user_timespec ts;
        boolean_t truncated_timeout = FALSE;

-       
-       if(uap->timeout) {
-               
+
+       if (uap->timeout) {

                if (IS_64BIT_PROCESS(p)) {
                        struct user64_timespec ts64;
                        error = copyin(uap->ts, &ts64, sizeof(ts64));
                if (IS_64BIT_PROCESS(p)) {
                        struct user64_timespec ts64;
                        error = copyin(uap->ts, &ts64, sizeof(ts64));

-                       ts.tv_sec = ts64.tv_sec;
-                       ts.tv_nsec = ts64.tv_nsec;
+                       ts.tv_sec = (user_time_t)ts64.tv_sec;
+                       ts.tv_nsec = (user_long_t)ts64.tv_nsec;

                } else {
                        struct user32_timespec ts32;
                        error = copyin(uap->ts, &ts32, sizeof(ts32));
                        ts.tv_sec = ts32.tv_sec;
                        ts.tv_nsec = ts32.tv_nsec;
                }
                } else {
                        struct user32_timespec ts32;
                        error = copyin(uap->ts, &ts32, sizeof(ts32));
                        ts.tv_sec = ts32.tv_sec;
                        ts.tv_nsec = ts32.tv_nsec;
                }

-               
+

                if (error) {
                        return error;
                }
                if (error) {
                        return error;
                }

-               
+

                if ((ts.tv_sec & 0xFFFFFFFF00000000ULL) != 0) {
                        ts.tv_sec = 0xFFFFFFFF;
                        ts.tv_nsec = 0;
                        truncated_timeout = TRUE;
                }
                if ((ts.tv_sec & 0xFFFFFFFF00000000ULL) != 0) {
                        ts.tv_sec = 0xFFFFFFFF;
                        ts.tv_nsec = 0;
                        truncated_timeout = TRUE;
                }

-               
+

                if (uap->relative) {
                if (uap->relative) {

-                       then.tv_sec = ts.tv_sec;
-                       then.tv_nsec = ts.tv_nsec;
+                       then.tv_sec = (unsigned int)ts.tv_sec;
+                       then.tv_nsec = (clock_res_t)ts.tv_nsec;

                } else {
                        nanotime(&now);
                } else {
                        nanotime(&now);

-                       
+

                        /* if time has elapsed, set time to null timepsec to bailout rightaway */
                        if (now.tv_sec == ts.tv_sec ?
                        /* if time has elapsed, set time to null timepsec to bailout rightaway */
                        if (now.tv_sec == ts.tv_sec ?

-                               now.tv_nsec > ts.tv_nsec :
-                               now.tv_sec > ts.tv_sec) {
+                           now.tv_nsec > ts.tv_nsec :
+                           now.tv_sec > ts.tv_sec) {

                                then.tv_sec = 0;
                                then.tv_nsec = 0;
                        } else {
                                then.tv_sec = 0;
                                then.tv_nsec = 0;
                        } else {

-                               then.tv_sec = ts.tv_sec - now.tv_sec;
-                               then.tv_nsec = ts.tv_nsec - now.tv_nsec;
+                               then.tv_sec = (unsigned int)(ts.tv_sec - now.tv_sec);
+                               then.tv_nsec = (clock_res_t)(ts.tv_nsec - now.tv_nsec);

                                if (then.tv_nsec < 0) {
                                        then.tv_nsec += NSEC_PER_SEC;
                                if (then.tv_nsec < 0) {
                                        then.tv_nsec += NSEC_PER_SEC;

-                                       then.tv_sec--; 
+                                       then.tv_sec--;

                                }
                        }
                }
                                }
                        }
                }

-               
-               if (uap->mutex_sem == 0)
+
+               if (uap->mutex_sem == 0) {

                        kern_result = semaphore_timedwait_trap_internal((mach_port_name_t)uap->cond_sem, then.tv_sec, then.tv_nsec, __posix_sem_syscall_return);
                        kern_result = semaphore_timedwait_trap_internal((mach_port_name_t)uap->cond_sem, then.tv_sec, then.tv_nsec, __posix_sem_syscall_return);

-               else
+               } else {

                        kern_result = semaphore_timedwait_signal_trap_internal(uap->cond_sem, uap->mutex_sem, then.tv_sec, then.tv_nsec, __posix_sem_syscall_return);
                        kern_result = semaphore_timedwait_signal_trap_internal(uap->cond_sem, uap->mutex_sem, then.tv_sec, then.tv_nsec, __posix_sem_syscall_return);

-               
+               }

        } else {
        } else {

-               
-               if (uap->mutex_sem == 0)
+               if (uap->mutex_sem == 0) {

                        kern_result = semaphore_wait_trap_internal(uap->cond_sem, __posix_sem_syscall_return);
                        kern_result = semaphore_wait_trap_internal(uap->cond_sem, __posix_sem_syscall_return);

-               else
-                       
+               } else {

                        kern_result = semaphore_wait_signal_trap_internal(uap->cond_sem, uap->mutex_sem, __posix_sem_syscall_return);
                        kern_result = semaphore_wait_signal_trap_internal(uap->cond_sem, uap->mutex_sem, __posix_sem_syscall_return);

+               }
+       }
+
+       if (kern_result == KERN_SUCCESS && !truncated_timeout) {
+               return 0;
+       } else if (kern_result == KERN_SUCCESS && truncated_timeout) {
+               return EINTR; /* simulate an exceptional condition because Mach doesn't support a longer timeout */
+       } else if (kern_result == KERN_ABORTED) {
+               return EINTR;
+       } else if (kern_result == KERN_OPERATION_TIMED_OUT) {
+               return ETIMEDOUT;
+       } else {
+               return EINVAL;

        }
        }

-       
-       if (kern_result == KERN_SUCCESS && !truncated_timeout)
-               return(0);
-       else if (kern_result == KERN_SUCCESS && truncated_timeout)
-               return(EINTR); /* simulate an exceptional condition because Mach doesn't support a longer timeout */
-       else if (kern_result == KERN_ABORTED)
-               return(EINTR);
-       else if (kern_result == KERN_OPERATION_TIMED_OUT) 
-               return(ETIMEDOUT);
-       else
-               return(EINVAL);

 }
 #endif /* OLD_SEMWAIT_SIGNAL*/
 
 }
 #endif /* OLD_SEMWAIT_SIGNAL*/
 


@@ -1052,96 +1181,96 @@ __old_semwait_signal_nocancel(proc_t p, struct __old_semwait_signal_nocancel_arg
  */
 int
 __semwait_signal(proc_t p, struct __semwait_signal_args *uap,
  */
 int
 __semwait_signal(proc_t p, struct __semwait_signal_args *uap,

-                     int32_t *retval)
+    int32_t *retval)

 {
        __pthread_testcancel(0);
 {
        __pthread_testcancel(0);

-       return(__semwait_signal_nocancel(p, (struct __semwait_signal_nocancel_args *)uap, retval));
+       return __semwait_signal_nocancel(p, (struct __semwait_signal_nocancel_args *)uap, retval);

 }
 
 int
 __semwait_signal_nocancel(__unused proc_t p, struct __semwait_signal_nocancel_args *uap,
 }
 
 int
 __semwait_signal_nocancel(__unused proc_t p, struct __semwait_signal_nocancel_args *uap,

-                              __unused int32_t *retval)
+    __unused int32_t *retval)

 {
 {

-       

        kern_return_t kern_result;
        mach_timespec_t then;
        struct timespec now;
        struct user_timespec ts;
        kern_return_t kern_result;
        mach_timespec_t then;
        struct timespec now;
        struct user_timespec ts;

-        boolean_t truncated_timeout = FALSE;
-       
-       if(uap->timeout) {
-                
-               ts.tv_sec = uap->tv_sec;
-                ts.tv_nsec = uap->tv_nsec;
-
-                if ((ts.tv_sec & 0xFFFFFFFF00000000ULL) != 0) {
-                        ts.tv_sec = 0xFFFFFFFF;
-                        ts.tv_nsec = 0;
-                        truncated_timeout = TRUE;
-                }              
-               
+       boolean_t truncated_timeout = FALSE;
+
+       if (uap->timeout) {
+               ts.tv_sec = (user_time_t)uap->tv_sec;
+               ts.tv_nsec = uap->tv_nsec;
+
+               if ((ts.tv_sec & 0xFFFFFFFF00000000ULL) != 0) {
+                       ts.tv_sec = 0xFFFFFFFF;
+                       ts.tv_nsec = 0;
+                       truncated_timeout = TRUE;
+               }
+

                if (uap->relative) {
                if (uap->relative) {

-                       then.tv_sec = ts.tv_sec;
-                       then.tv_nsec = ts.tv_nsec;
+                       then.tv_sec = (unsigned int)ts.tv_sec;
+                       then.tv_nsec = (clock_res_t)ts.tv_nsec;

                } else {
                        nanotime(&now);
 
                } else {
                        nanotime(&now);
 

-                        /* if time has elapsed, set time to null timepsec to bailout rightaway */
-                        if (now.tv_sec == ts.tv_sec ?
-                                now.tv_nsec > ts.tv_nsec :
-                                now.tv_sec > ts.tv_sec) {
-                                then.tv_sec = 0;
-                                then.tv_nsec = 0;
-                        } else {
-                                then.tv_sec = ts.tv_sec - now.tv_sec;
-                                then.tv_nsec = ts.tv_nsec - now.tv_nsec;
-                                if (then.tv_nsec < 0) {
-                                        then.tv_nsec += NSEC_PER_SEC;
-                                        then.tv_sec--;
-                                }
-                        }
-               }
-                                       
-               if (uap->mutex_sem == 0)
+                       /* if time has elapsed, set time to null timepsec to bailout rightaway */
+                       if (now.tv_sec == ts.tv_sec ?
+                           now.tv_nsec > ts.tv_nsec :
+                           now.tv_sec > ts.tv_sec) {
+                               then.tv_sec = 0;
+                               then.tv_nsec = 0;
+                       } else {
+                               then.tv_sec = (unsigned int)(ts.tv_sec - now.tv_sec);
+                               then.tv_nsec = (clock_res_t)(ts.tv_nsec - now.tv_nsec);
+                               if (then.tv_nsec < 0) {
+                                       then.tv_nsec += NSEC_PER_SEC;
+                                       then.tv_sec--;
+                               }
+                       }
+               }
+
+               if (uap->mutex_sem == 0) {

                        kern_result = semaphore_timedwait_trap_internal((mach_port_name_t)uap->cond_sem, then.tv_sec, then.tv_nsec, __posix_sem_syscall_return);
                        kern_result = semaphore_timedwait_trap_internal((mach_port_name_t)uap->cond_sem, then.tv_sec, then.tv_nsec, __posix_sem_syscall_return);

-               else
+               } else {

                        kern_result = semaphore_timedwait_signal_trap_internal(uap->cond_sem, uap->mutex_sem, then.tv_sec, then.tv_nsec, __posix_sem_syscall_return);
                        kern_result = semaphore_timedwait_signal_trap_internal(uap->cond_sem, uap->mutex_sem, then.tv_sec, then.tv_nsec, __posix_sem_syscall_return);

-               
+               }

        } else {
        } else {

-               
-               if (uap->mutex_sem == 0)
+               if (uap->mutex_sem == 0) {

                        kern_result = semaphore_wait_trap_internal(uap->cond_sem, __posix_sem_syscall_return);
                        kern_result = semaphore_wait_trap_internal(uap->cond_sem, __posix_sem_syscall_return);

-               else
-                       
+               } else {

                        kern_result = semaphore_wait_signal_trap_internal(uap->cond_sem, uap->mutex_sem, __posix_sem_syscall_return);
                        kern_result = semaphore_wait_signal_trap_internal(uap->cond_sem, uap->mutex_sem, __posix_sem_syscall_return);

+               }
+       }
+
+       if (kern_result == KERN_SUCCESS && !truncated_timeout) {
+               return 0;
+       } else if (kern_result == KERN_SUCCESS && truncated_timeout) {
+               return EINTR; /* simulate an exceptional condition because Mach doesn't support a longer timeout */
+       } else if (kern_result == KERN_ABORTED) {
+               return EINTR;
+       } else if (kern_result == KERN_OPERATION_TIMED_OUT) {
+               return ETIMEDOUT;
+       } else {
+               return EINVAL;

        }
        }

-       
-       if (kern_result == KERN_SUCCESS && !truncated_timeout)
-                return(0);
-        else if (kern_result == KERN_SUCCESS && truncated_timeout)
-                return(EINTR); /* simulate an exceptional condition because Mach doesn't support a longer timeout */
-       else if (kern_result == KERN_ABORTED)
-               return(EINTR);
-       else if (kern_result == KERN_OPERATION_TIMED_OUT) 
-               return(ETIMEDOUT);
-       else
-               return(EINVAL);

 }
 
 
 }
 
 

-int 
+int

 __pthread_kill(__unused proc_t p, struct __pthread_kill_args *uap,
 __pthread_kill(__unused proc_t p, struct __pthread_kill_args *uap,

-              __unused int32_t *retval) 
+    __unused int32_t *retval)

 {
        thread_t target_act;
        int error = 0;
        int signum = uap->sig;
        struct uthread *uth;
 
 {
        thread_t target_act;
        int error = 0;
        int signum = uap->sig;
        struct uthread *uth;
 

-       target_act = (thread_t)port_name_to_thread(uap->thread_port);
+       target_act = (thread_t)port_name_to_thread(uap->thread_port,
+           PORT_TO_THREAD_NONE);

 
 

-       if (target_act == THREAD_NULL)
-               return (ESRCH);
+       if (target_act == THREAD_NULL) {
+               return ESRCH;
+       }

        if ((u_int)signum >= NSIG) {
                error = EINVAL;
                goto out;
        if ((u_int)signum >= NSIG) {
                error = EINVAL;
                goto out;


@@ -1154,17 +1283,23 @@ __pthread_kill(__unused proc_t p, struct __pthread_kill_args *uap,
                goto out;
        }
 
                goto out;
        }
 

-       if (signum)
+       if ((thread_get_tag(target_act) & THREAD_TAG_WORKQUEUE) && !uth->uu_workq_pthread_kill_allowed) {
+               error = ENOTSUP;
+               goto out;
+       }
+
+       if (signum) {

                psignal_uthread(target_act, signum);
                psignal_uthread(target_act, signum);

+       }

 out:
        thread_deallocate(target_act);
 out:
        thread_deallocate(target_act);

-       return (error);
+       return error;

 }
 
 
 }
 
 

-int 
+int

 __pthread_sigmask(__unused proc_t p, struct __pthread_sigmask_args *uap,
 __pthread_sigmask(__unused proc_t p, struct __pthread_sigmask_args *uap,

-                 __unused int32_t *retval)
+    __unused int32_t *retval)

 {
        user_addr_t set = uap->set;
        user_addr_t oset = uap->oset;
 {
        user_addr_t set = uap->set;
        user_addr_t oset = uap->oset;


@@ -1182,8 +1317,9 @@ __pthread_sigmask(__unused proc_t p, struct __pthread_sigmask_args *uap,
        }
 
        error = copyin(set, &nset, sizeof(sigset_t));
        }
 
        error = copyin(set, &nset, sizeof(sigset_t));

-       if (error)
+       if (error) {

                goto out;
                goto out;

+       }

 
        switch (uap->how) {
        case SIG_BLOCK:
 
        switch (uap->how) {
        case SIG_BLOCK:


@@ -1199,16 +1335,16 @@ __pthread_sigmask(__unused proc_t p, struct __pthread_sigmask_args *uap,
                ut->uu_sigmask = (nset & ~sigcantmask);
                signal_setast(current_thread());
                break;
                ut->uu_sigmask = (nset & ~sigcantmask);
                signal_setast(current_thread());
                break;

-       
+

        default:
                error = EINVAL;
        default:
                error = EINVAL;

-

        }
 out:
        }
 out:

-       if (!error && oset != USER_ADDR_NULL)
+       if (!error && oset != USER_ADDR_NULL) {

                copyout(&oldset, oset, sizeof(sigset_t));
                copyout(&oldset, oset, sizeof(sigset_t));

+       }

 
 

-       return(error);
+       return error;

 }
 
 /*
 }
 
 /*


@@ -1217,14 +1353,14 @@ out:
  *     copyin:EFAULT
  *     copyout:EFAULT
  */
  *     copyin:EFAULT
  *     copyout:EFAULT
  */

-int 
+int

 __sigwait(proc_t p, struct __sigwait_args *uap, int32_t *retval)
 {
        __pthread_testcancel(1);
 __sigwait(proc_t p, struct __sigwait_args *uap, int32_t *retval)
 {
        __pthread_testcancel(1);

-       return(__sigwait_nocancel(p, (struct __sigwait_nocancel_args *)uap, retval));
+       return __sigwait_nocancel(p, (struct __sigwait_nocancel_args *)uap, retval);

 }
 
 }
 

-int 
+int

 __sigwait_nocancel(proc_t p, struct __sigwait_nocancel_args *uap, __unused int32_t *retval)
 {
        struct uthread *ut;
 __sigwait_nocancel(proc_t p, struct __sigwait_nocancel_args *uap, __unused int32_t *retval)
 {
        struct uthread *ut;


@@ -1232,31 +1368,34 @@ __sigwait_nocancel(proc_t p, struct __sigwait_nocancel_args *uap, __unused int32
        int error = 0;
        sigset_t mask;
        sigset_t siglist;
        int error = 0;
        sigset_t mask;
        sigset_t siglist;

-       sigset_t sigw=0;
+       sigset_t sigw = 0;

        int signum;
 
        ut = (struct uthread *)get_bsdthread_info(current_thread());
 
        int signum;
 
        ut = (struct uthread *)get_bsdthread_info(current_thread());
 

-       if (uap->set == USER_ADDR_NULL)
-               return(EINVAL);
+       if (uap->set == USER_ADDR_NULL) {
+               return EINVAL;
+       }

 
        error = copyin(uap->set, &mask, sizeof(sigset_t));
 
        error = copyin(uap->set, &mask, sizeof(sigset_t));

-       if (error)
-               return(error);
+       if (error) {
+               return error;
+       }

 
        siglist = (mask & ~sigcantmask);
 
 
        siglist = (mask & ~sigcantmask);
 

-       if (siglist == 0)
-               return(EINVAL);
+       if (siglist == 0) {
+               return EINVAL;
+       }

 
        proc_lock(p);
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
                proc_unlock(p);
 
        proc_lock(p);
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
                proc_unlock(p);

-               return(EINVAL);
+               return EINVAL;

        } else {
                proc_signalstart(p, 1);
                TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
        } else {
                proc_signalstart(p, 1);
                TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {

-                       if ( (sigw = uth->uu_siglist & siglist) ) {
+                       if ((sigw = uth->uu_siglist & siglist)) {

                                break;
                        }
                }
                                break;
                        }
                }


@@ -1274,22 +1413,23 @@ __sigwait_nocancel(proc_t p, struct __sigwait_nocancel_args *uap, __unused int32
         * save it here and mark the sigacts structure
         * to indicate this.
         */
         * save it here and mark the sigacts structure
         * to indicate this.
         */

-       uth = ut;               /* wait for it to be delivered to us */
+       uth = ut;               /* wait for it to be delivered to us */

        ut->uu_oldmask = ut->uu_sigmask;
        ut->uu_flag |= UT_SAS_OLDMASK;
        if (siglist == (sigset_t)0) {
                proc_unlock(p);
        ut->uu_oldmask = ut->uu_sigmask;
        ut->uu_flag |= UT_SAS_OLDMASK;
        if (siglist == (sigset_t)0) {
                proc_unlock(p);

-               return(EINVAL);
+               return EINVAL;

        }
        /* SIGKILL and SIGSTOP are not maskable as well */
        }
        /* SIGKILL and SIGSTOP are not maskable as well */

-       ut->uu_sigmask = ~(siglist|sigcantmask);
-       ut->uu_sigwait = siglist; 
+       ut->uu_sigmask = ~(siglist | sigcantmask);
+       ut->uu_sigwait = siglist;

 
        /* No Continuations for now */
 
        /* No Continuations for now */

-       error =  msleep((caddr_t)&ut->uu_sigwait, &p->p_mlock, PPAUSE|PCATCH, "pause", 0);
+       error =  msleep((caddr_t)&ut->uu_sigwait, &p->p_mlock, PPAUSE | PCATCH, "pause", 0);

 
 

-       if (error == ERESTART)
+       if (error == ERESTART) {

                error = 0;
                error = 0;

+       }

 
        sigw = (ut->uu_sigwait & siglist);
        ut->uu_sigmask = ut->uu_oldmask;
 
        sigw = (ut->uu_sigwait & siglist);
        ut->uu_sigmask = ut->uu_oldmask;


@@ -1299,8 +1439,9 @@ sigwait1:
        ut->uu_sigwait = 0;
        if (!error) {
                signum = ffs((unsigned int)sigw);
        ut->uu_sigwait = 0;
        if (!error) {
                signum = ffs((unsigned int)sigw);

-               if (!signum)
+               if (!signum) {

                        panic("sigwait with no signal wakeup");
                        panic("sigwait with no signal wakeup");

+               }

                /* Clear the pending signal in the thread it was delivered */
                uth->uu_siglist &= ~(sigmask(signum));
 
                /* Clear the pending signal in the thread it was delivered */
                uth->uu_siglist &= ~(sigmask(signum));
 


@@ -1309,13 +1450,14 @@ sigwait1:
 #endif
 
                proc_unlock(p);
 #endif
 
                proc_unlock(p);

-               if (uap->sig != USER_ADDR_NULL)
-                               error = copyout(&signum, uap->sig, sizeof(int));
-       } else
+               if (uap->sig != USER_ADDR_NULL) {
+                       error = copyout(&signum, uap->sig, sizeof(int));
+               }
+       } else {

                proc_unlock(p);
                proc_unlock(p);

+       }

 
 

-       return(error);
-
+       return error;

 }
 
 int
 }
 
 int


@@ -1330,24 +1472,27 @@ sigaltstack(__unused proc_t p, struct sigaltstack_args *uap, __unused int32_t *r
        uth = (struct uthread *)get_bsdthread_info(current_thread());
 
        pstk = &uth->uu_sigstk;
        uth = (struct uthread *)get_bsdthread_info(current_thread());
 
        pstk = &uth->uu_sigstk;

-       if ((uth->uu_flag & UT_ALTSTACK) == 0)
+       if ((uth->uu_flag & UT_ALTSTACK) == 0) {

                uth->uu_sigstk.ss_flags |= SA_DISABLE;
                uth->uu_sigstk.ss_flags |= SA_DISABLE;

+       }

        onstack = pstk->ss_flags & SA_ONSTACK;
        if (uap->oss) {
                if (IS_64BIT_PROCESS(p)) {
        onstack = pstk->ss_flags & SA_ONSTACK;
        if (uap->oss) {
                if (IS_64BIT_PROCESS(p)) {

-                       struct user64_sigaltstack ss64;
-                       sigaltstack_kern_to_user64(pstk, &ss64);                        
+                       struct user64_sigaltstack ss64 = {};
+                       sigaltstack_kern_to_user64(pstk, &ss64);

                        error = copyout(&ss64, uap->oss, sizeof(ss64));
                } else {
                        error = copyout(&ss64, uap->oss, sizeof(ss64));
                } else {

-                       struct user32_sigaltstack ss32;
-                       sigaltstack_kern_to_user32(pstk, &ss32);                        
+                       struct user32_sigaltstack ss32 = {};
+                       sigaltstack_kern_to_user32(pstk, &ss32);

                        error = copyout(&ss32, uap->oss, sizeof(ss32));
                }
                        error = copyout(&ss32, uap->oss, sizeof(ss32));
                }

-               if (error)
-                       return (error);
+               if (error) {
+                       return error;
+               }
+       }
+       if (uap->nss == USER_ADDR_NULL) {
+               return 0;

        }
        }

-       if (uap->nss == USER_ADDR_NULL)
-               return (0);

        if (IS_64BIT_PROCESS(p)) {
                struct user64_sigaltstack ss64;
                error = copyin(uap->nss, &ss64, sizeof(ss64));
        if (IS_64BIT_PROCESS(p)) {
                struct user64_sigaltstack ss64;
                error = copyin(uap->nss, &ss64, sizeof(ss64));


@@ -1357,29 +1502,33 @@ sigaltstack(__unused proc_t p, struct sigaltstack_args *uap, __unused int32_t *r
                error = copyin(uap->nss, &ss32, sizeof(ss32));
                sigaltstack_user32_to_kern(&ss32, &ss);
        }
                error = copyin(uap->nss, &ss32, sizeof(ss32));
                sigaltstack_user32_to_kern(&ss32, &ss);
        }

-       if (error)
-               return (error);
-       if ((ss.ss_flags & ~SA_DISABLE) != 0)  {
-               return(EINVAL);
+       if (error) {
+               return error;
+       }
+       if ((ss.ss_flags & ~SA_DISABLE) != 0) {
+               return EINVAL;

        }
 
        if (ss.ss_flags & SA_DISABLE) {
                /* if we are here we are not in the signal handler ;so no need to check */
        }
 
        if (ss.ss_flags & SA_DISABLE) {
                /* if we are here we are not in the signal handler ;so no need to check */

-               if (uth->uu_sigstk.ss_flags & SA_ONSTACK)
-                       return (EINVAL);
+               if (uth->uu_sigstk.ss_flags & SA_ONSTACK) {
+                       return EINVAL;
+               }

                uth->uu_flag &= ~UT_ALTSTACK;
                uth->uu_sigstk.ss_flags = ss.ss_flags;
                uth->uu_flag &= ~UT_ALTSTACK;
                uth->uu_sigstk.ss_flags = ss.ss_flags;

-               return (0);
+               return 0;
+       }
+       if (onstack) {
+               return EPERM;

        }
        }

-       if (onstack)
-               return (EPERM);

 /* The older stacksize was 8K, enforce that one so no compat problems */
 #define OLDMINSIGSTKSZ 8*1024
 /* The older stacksize was 8K, enforce that one so no compat problems */
 #define OLDMINSIGSTKSZ 8*1024

-       if (ss.ss_size < OLDMINSIGSTKSZ)
-               return (ENOMEM);
+       if (ss.ss_size < OLDMINSIGSTKSZ) {
+               return ENOMEM;
+       }

        uth->uu_flag |= UT_ALTSTACK;
        uth->uu_flag |= UT_ALTSTACK;

-       uth->uu_sigstk= ss;
-       return (0);
+       uth->uu_sigstk = ss;
+       return 0;

 }
 
 int
 }
 
 int


@@ -1387,150 +1536,336 @@ kill(proc_t cp, struct kill_args *uap, __unused int32_t *retval)
 {
        proc_t p;
        kauth_cred_t uc = kauth_cred_get();
 {
        proc_t p;
        kauth_cred_t uc = kauth_cred_get();

-       int posix = uap->posix;         /* !0 if posix behaviour desired */
+       int posix = uap->posix;         /* !0 if posix behaviour desired */

 
 

-       AUDIT_ARG(pid, uap->pid);
-       AUDIT_ARG(signum, uap->signum);
+       AUDIT_ARG(pid, uap->pid);
+       AUDIT_ARG(signum, uap->signum);

 
 

-       if ((u_int)uap->signum >= NSIG)
-               return (EINVAL);
+       if ((u_int)uap->signum >= NSIG) {
+               return EINVAL;
+       }

        if (uap->pid > 0) {
                /* kill single process */
                if ((p = proc_find(uap->pid)) == NULL) {
                        if ((p = pzfind(uap->pid)) != NULL) {
                                /*
        if (uap->pid > 0) {
                /* kill single process */
                if ((p = proc_find(uap->pid)) == NULL) {
                        if ((p = pzfind(uap->pid)) != NULL) {
                                /*

-                                * IEEE Std 1003.1-2001: return success
-                                * when killing a zombie.
+                                * POSIX 1003.1-2001 requires returning success when killing a
+                                * zombie; see Rationale for kill(2).

                                 */
                                 */

-                               return (0);
+                               return 0;

                        }
                        }

-                       return (ESRCH);
+                       return ESRCH;

                }
                AUDIT_ARG(process, p);
                }
                AUDIT_ARG(process, p);

-               if (!cansignal(cp, uc, p, uap->signum, 0)) {
+               if (!cansignal(cp, uc, p, uap->signum)) {

                        proc_rele(p);
                        proc_rele(p);

-                       return(EPERM);
+                       return EPERM;

                }
                }

-               if (uap->signum)
+               if (uap->signum) {

                        psignal(p, uap->signum);
                        psignal(p, uap->signum);

+               }

                proc_rele(p);
                proc_rele(p);

-               return (0);
+               return 0;

        }
        switch (uap->pid) {
        }
        switch (uap->pid) {

-       case -1:                /* broadcast signal */
-               return (killpg1(cp, uap->signum, 0, 1, posix));
-       case 0:                 /* signal own process group */
-               return (killpg1(cp, uap->signum, 0, 0, posix));
-       default:                /* negative explicit process group */
-               return (killpg1(cp, uap->signum, -(uap->pid), 0, posix));
+       case -1: /* broadcast signal */
+               return killpg1(cp, uap->signum, 0, 1, posix);
+       case 0: /* signal own process group */
+               return killpg1(cp, uap->signum, 0, 0, posix);
+       default: /* negative explicit process group */
+               return killpg1(cp, uap->signum, -(uap->pid), 0, posix);

        }
        /* NOTREACHED */
 }
 
        }
        /* NOTREACHED */
 }
 

-static int
-killpg1_filt(proc_t p, void * arg)
+os_reason_t
+build_userspace_exit_reason(uint32_t reason_namespace, uint64_t reason_code, user_addr_t payload, uint32_t payload_size,
+    user_addr_t reason_string, uint64_t reason_flags)

 {
 {

-       struct killpg1_filtargs * kfargp = (struct killpg1_filtargs *)arg;
-       proc_t cp = kfargp->cp;
-       int posix = kfargp->posix;
+       os_reason_t exit_reason = OS_REASON_NULL;

 
 

+       int error = 0;
+       int num_items_to_copy = 0;
+       uint32_t user_data_to_copy = 0;
+       char *reason_user_desc = NULL;
+       size_t reason_user_desc_len = 0;

 
 

-       if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
-               (!posix && p == cp))
-               return(0);
-       else
-               return(1);
-}
+       exit_reason = os_reason_create(reason_namespace, reason_code);
+       if (exit_reason == OS_REASON_NULL) {
+               printf("build_userspace_exit_reason: failed to allocate exit reason\n");
+               return exit_reason;
+       }
+
+       exit_reason->osr_flags |= OS_REASON_FLAG_FROM_USERSPACE;
+
+       /*
+        * Only apply flags that are allowed to be passed from userspace.
+        */
+       exit_reason->osr_flags |= (reason_flags & OS_REASON_FLAG_MASK_ALLOWED_FROM_USER);
+       if ((reason_flags & OS_REASON_FLAG_MASK_ALLOWED_FROM_USER) != reason_flags) {
+               printf("build_userspace_exit_reason: illegal flags passed from userspace (some masked off) 0x%llx, ns: %u, code 0x%llx\n",
+                   reason_flags, reason_namespace, reason_code);
+       }
+
+       if (!(exit_reason->osr_flags & OS_REASON_FLAG_NO_CRASH_REPORT)) {
+               exit_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT;
+       }
+
+       if (payload != USER_ADDR_NULL) {
+               if (payload_size == 0) {
+                       printf("build_userspace_exit_reason: exit reason with namespace %u, nonzero payload but zero length\n",
+                           reason_namespace);
+                       exit_reason->osr_flags |= OS_REASON_FLAG_BAD_PARAMS;
+                       payload = USER_ADDR_NULL;
+               } else {
+                       num_items_to_copy++;
+
+                       if (payload_size > EXIT_REASON_PAYLOAD_MAX_LEN) {
+                               exit_reason->osr_flags |= OS_REASON_FLAG_PAYLOAD_TRUNCATED;
+                               payload_size = EXIT_REASON_PAYLOAD_MAX_LEN;
+                       }
+
+                       user_data_to_copy += payload_size;
+               }
+       }
+
+       if (reason_string != USER_ADDR_NULL) {
+               reason_user_desc = kheap_alloc(KHEAP_TEMP,
+                   EXIT_REASON_USER_DESC_MAX_LEN, Z_WAITOK);
+
+               if (reason_user_desc != NULL) {
+                       error = copyinstr(reason_string, (void *) reason_user_desc,
+                           EXIT_REASON_USER_DESC_MAX_LEN, &reason_user_desc_len);
+
+                       if (error == 0) {
+                               num_items_to_copy++;
+                               user_data_to_copy += reason_user_desc_len;
+                       } else if (error == ENAMETOOLONG) {
+                               num_items_to_copy++;
+                               reason_user_desc[EXIT_REASON_USER_DESC_MAX_LEN - 1] = '\0';
+                               user_data_to_copy += reason_user_desc_len;
+                       } else {
+                               exit_reason->osr_flags |= OS_REASON_FLAG_FAILED_DATA_COPYIN;
+                               kheap_free(KHEAP_TEMP, reason_user_desc,
+                                   EXIT_REASON_USER_DESC_MAX_LEN);
+                               reason_user_desc = NULL;
+                               reason_user_desc_len = 0;
+                       }
+               }
+       }
+
+       if (num_items_to_copy != 0) {
+               uint32_t reason_buffer_size_estimate = 0;
+               mach_vm_address_t data_addr = 0;

 
 

+               reason_buffer_size_estimate = kcdata_estimate_required_buffer_size(num_items_to_copy, user_data_to_copy);
+
+               error = os_reason_alloc_buffer(exit_reason, reason_buffer_size_estimate);
+               if (error != 0) {
+                       printf("build_userspace_exit_reason: failed to allocate signal reason buffer\n");
+                       goto out_failed_copyin;
+               }
+
+               if (reason_user_desc != NULL && reason_user_desc_len != 0) {
+                       if (KERN_SUCCESS == kcdata_get_memory_addr(&exit_reason->osr_kcd_descriptor,
+                           EXIT_REASON_USER_DESC,
+                           (uint32_t)reason_user_desc_len,
+                           &data_addr)) {
+                               kcdata_memcpy(&exit_reason->osr_kcd_descriptor, (mach_vm_address_t) data_addr,
+                                   reason_user_desc, (uint32_t)reason_user_desc_len);
+                       } else {
+                               printf("build_userspace_exit_reason: failed to allocate space for reason string\n");
+                               goto out_failed_copyin;
+                       }
+               }
+
+               if (payload != USER_ADDR_NULL) {
+                       if (KERN_SUCCESS ==
+                           kcdata_get_memory_addr(&exit_reason->osr_kcd_descriptor,
+                           EXIT_REASON_USER_PAYLOAD,
+                           payload_size,
+                           &data_addr)) {
+                               error = copyin(payload, (void *) data_addr, payload_size);
+                               if (error) {
+                                       printf("build_userspace_exit_reason: failed to copy in payload data with error %d\n", error);
+                                       goto out_failed_copyin;
+                               }
+                       } else {
+                               printf("build_userspace_exit_reason: failed to allocate space for payload data\n");
+                               goto out_failed_copyin;
+                       }
+               }
+       }
+
+       if (reason_user_desc != NULL) {
+               kheap_free(KHEAP_TEMP, reason_user_desc, EXIT_REASON_USER_DESC_MAX_LEN);
+               reason_user_desc = NULL;
+               reason_user_desc_len = 0;
+       }
+
+       return exit_reason;
+
+out_failed_copyin:
+
+       if (reason_user_desc != NULL) {
+               kheap_free(KHEAP_TEMP, reason_user_desc, EXIT_REASON_USER_DESC_MAX_LEN);
+               reason_user_desc = NULL;
+               reason_user_desc_len = 0;
+       }
+
+       exit_reason->osr_flags |= OS_REASON_FLAG_FAILED_DATA_COPYIN;
+       os_reason_alloc_buffer(exit_reason, 0);
+       return exit_reason;
+}

 
 static int
 
 static int

-killpg1_pgrpfilt(proc_t p, __unused void * arg)
+terminate_with_payload_internal(struct proc *cur_proc, int target_pid, uint32_t reason_namespace,
+    uint64_t reason_code, user_addr_t payload, uint32_t payload_size,
+    user_addr_t reason_string, uint64_t reason_flags)
+{
+       proc_t target_proc = PROC_NULL;
+       kauth_cred_t cur_cred = kauth_cred_get();
+
+       os_reason_t signal_reason = OS_REASON_NULL;
+
+       AUDIT_ARG(pid, target_pid);
+       if ((target_pid <= 0)) {
+               return EINVAL;
+       }
+
+       target_proc = proc_find(target_pid);
+       if (target_proc == PROC_NULL) {
+               return ESRCH;
+       }
+
+       AUDIT_ARG(process, target_proc);
+
+       if (!cansignal(cur_proc, cur_cred, target_proc, SIGKILL)) {
+               proc_rele(target_proc);
+               return EPERM;
+       }
+
+       if (target_pid != cur_proc->p_pid) {
+               /*
+                * FLAG_ABORT should only be set on terminate_with_reason(getpid()) that
+                * was a fallback from an unsuccessful abort_with_reason(). In that case
+                * caller's pid matches the target one. Otherwise remove the flag.
+                */
+               reason_flags &= ~((typeof(reason_flags))OS_REASON_FLAG_ABORT);
+       }
+
+       KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+           target_proc->p_pid, reason_namespace,
+           reason_code, 0, 0);
+
+       signal_reason = build_userspace_exit_reason(reason_namespace, reason_code, payload, payload_size,
+           reason_string, (reason_flags | OS_REASON_FLAG_NO_CRASHED_TID));
+
+       if (target_pid == cur_proc->p_pid) {
+               /*
+                * psignal_thread_with_reason() will pend a SIGKILL on the specified thread or
+                * return if the thread and/or task are already terminating. Either way, the
+                * current thread won't return to userspace.
+                */
+               psignal_thread_with_reason(target_proc, current_thread(), SIGKILL, signal_reason);
+       } else {
+               psignal_with_reason(target_proc, SIGKILL, signal_reason);
+       }
+
+       proc_rele(target_proc);
+
+       return 0;
+}
+
+int
+terminate_with_payload(struct proc *cur_proc, struct terminate_with_payload_args *args,
+    __unused int32_t *retval)

 {
 {

-        if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
-                (p->p_stat == SZOMB))
-                return(0);
-        else
-                return(1);
+       return terminate_with_payload_internal(cur_proc, args->pid, args->reason_namespace, args->reason_code, args->payload,
+                  args->payload_size, args->reason_string, args->reason_flags);

 }
 
 }
 

+static int
+killpg1_allfilt(proc_t p, void * arg)
+{
+       struct killpg1_filtargs * kfargp = (struct killpg1_filtargs *)arg;

 
 

+       /*
+        * Don't signal initproc, a system process, or the current process if POSIX
+        * isn't specified.
+        */
+       return p->p_pid > 1 && !(p->p_flag & P_SYSTEM) &&
+              (kfargp->posix ? true : p != kfargp->curproc);
+}

 
 static int
 
 static int

-killpg1_callback(proc_t p, void * arg)
-{
-       struct killpg1_iterargs * kargp = (struct killpg1_iterargs *)arg;
-        proc_t cp = kargp->cp;
-        kauth_cred_t uc = kargp->uc;   /* refcounted by the caller safe to use internal fields */
-        int signum = kargp->signum;
-       int * nfoundp = kargp->nfoundp;
-       int n;
-       int zombie = 0;
-       int error = 0;
+killpg1_pgrpfilt(proc_t p, __unused void * arg)
+{
+       /* XXX shouldn't this allow signalling zombies? */
+       return p->p_pid > 1 && !(p->p_flag & P_SYSTEM) && p->p_stat != SZOMB;
+}

 
 

-       if ((kargp->zombie != 0) && ((p->p_listflag & P_LIST_EXITED) == P_LIST_EXITED))
-               zombie = 1;
+static int
+killpg1_callback(proc_t p, void *arg)
+{
+       struct killpg1_iterargs *kargp = (struct killpg1_iterargs *)arg;
+       int signum = kargp->signum;

 
 

-       if (zombie != 0) {
-               proc_list_lock();
-               error = cansignal(cp, uc, p, signum, zombie);
-               proc_list_unlock();
-       
-               if (error != 0 && nfoundp != NULL) {
-                       n = *nfoundp;
-                       *nfoundp = n+1;
+       if ((p->p_listflag & P_LIST_EXITED) == P_LIST_EXITED) {
+               /*
+                * Count zombies as found for the purposes of signalling, since POSIX
+                * 1003.1-2001 sees signalling zombies as successful.  If killpg(2) or
+                * kill(2) with pid -1 only finds zombies that can be signalled, it
+                * shouldn't return ESRCH.  See the Rationale for kill(2).
+                *
+                * Don't call into MAC -- it's not expecting signal checks for exited
+                * processes.
+                */
+               if (cansignal_nomac(kargp->curproc, kargp->uc, p, signum)) {
+                       kargp->nfound++;

                }
                }

-       } else {
-               if (cansignal(cp, uc, p, signum, 0) == 0)
-                       return(PROC_RETURNED);
+       } else if (cansignal(kargp->curproc, kargp->uc, p, signum)) {
+               kargp->nfound++;

 
 

-               if (nfoundp != NULL) {
-                       n = *nfoundp;
-                       *nfoundp = n+1;
-               }
-               if (signum != 0)
+               if (signum != 0) {

                        psignal(p, signum);
                        psignal(p, signum);

+               }

        }
 
        }
 

-       return(PROC_RETURNED);
+       return PROC_RETURNED;

 }
 
 /*
  * Common code for kill process group/broadcast kill.
 }
 
 /*
  * Common code for kill process group/broadcast kill.

- * cp is calling process.

  */
 int
  */
 int

-killpg1(proc_t cp, int signum, int pgid, int all, int posix)
+killpg1(proc_t curproc, int signum, int pgid, int all, int posix)

 {
        kauth_cred_t uc;
        struct pgrp *pgrp;
 {
        kauth_cred_t uc;
        struct pgrp *pgrp;

-       int nfound = 0;
-       struct killpg1_iterargs karg;
-       struct killpg1_filtargs kfarg;

        int error = 0;
        int error = 0;

-       
-       uc = kauth_cred_proc_ref(cp);
-       if (all) {
-               /* 
-                * broadcast 
-                */
-               kfarg.posix = posix;
-               kfarg.cp = cp;

 
 

-               karg.cp = cp;
-               karg.uc = uc;
-               karg.nfoundp = &nfound;
-               karg.signum = signum;
-               karg.zombie = 1;
-
-               proc_iterate((PROC_ALLPROCLIST | PROC_ZOMBPROCLIST), killpg1_callback, &karg, killpg1_filt, (void *)&kfarg);
+       uc = kauth_cred_proc_ref(curproc);
+       struct killpg1_iterargs karg = {
+               .curproc = curproc, .uc = uc, .nfound = 0, .signum = signum
+       };

 
 

+       if (all) {
+               /*
+                * Broadcast to all processes that the user can signal (pid was -1).
+                */
+               struct killpg1_filtargs kfarg = {
+                       .posix = posix, .curproc = curproc
+               };
+               proc_iterate(PROC_ALLPROCLIST | PROC_ZOMBPROCLIST, killpg1_callback,
+                   &karg, killpg1_allfilt, &kfarg);

        } else {
                if (pgid == 0) {
        } else {
                if (pgid == 0) {

-                       /* 
-                        * zero pgid means send to my process group.
+                       /*
+                        * Send to current the current process' process group.

                         */
                         */

-                       pgrp = proc_pgrp(cp);
-                } else {
+                       pgrp = proc_pgrp(curproc);
+               } else {

                        pgrp = pgfind(pgid);
                        if (pgrp == NULL) {
                                error = ESRCH;
                        pgrp = pgfind(pgid);
                        if (pgrp == NULL) {
                                error = ESRCH;


@@ -1538,24 +1873,16 @@ killpg1(proc_t cp, int signum, int pgid, int all, int posix)
                        }
                }
 
                        }
                }
 

-                karg.nfoundp = &nfound;
-                karg.uc = uc;
-                karg.signum = signum;
-               karg.cp = cp;
-               karg.zombie = 0;
-
-

                /* PGRP_DROPREF drops the pgrp refernce */
                /* PGRP_DROPREF drops the pgrp refernce */

-               pgrp_iterate(pgrp, PGRP_BLOCKITERATE | PGRP_DROPREF, killpg1_callback, &karg,
-                       killpg1_pgrpfilt, NULL);
+               pgrp_iterate(pgrp, PGRP_DROPREF, killpg1_callback, &karg,
+                   killpg1_pgrpfilt, NULL);

        }
        }

-       error =  (nfound ? 0 : (posix ? EPERM : ESRCH));
+       error = (karg.nfound > 0 ? 0 : (posix ? EPERM : ESRCH));

 out:
        kauth_cred_unref(&uc);
 out:
        kauth_cred_unref(&uc);

-       return (error);
+       return error;

 }
 
 }
 

-

 /*
  * Send a signal to a process group.
  */
 /*
  * Send a signal to a process group.
  */


@@ -1580,20 +1907,21 @@ pgsignal_filt(proc_t p, void * arg)
 {
        int checkctty = *(int*)arg;
 
 {
        int checkctty = *(int*)arg;
 

-       if ((checkctty == 0) || p->p_flag & P_CONTROLT)
-               return(1);
-       else 
-               return(0);
+       if ((checkctty == 0) || p->p_flag & P_CONTROLT) {
+               return 1;
+       } else {
+               return 0;
+       }

 }
 
 
 static int
 pgsignal_callback(proc_t p, void * arg)
 {
 }
 
 
 static int
 pgsignal_callback(proc_t p, void * arg)
 {

-        int  signum = *(int*)arg;
+       int  signum = *(int*)arg;

 
        psignal(p, signum);
 
        psignal(p, signum);

-       return(PROC_RETURNED);
+       return PROC_RETURNED;

 }
 
 
 }
 
 


@@ -1601,7 +1929,7 @@ void
 pgsignal(struct pgrp *pgrp, int signum, int checkctty)
 {
        if (pgrp != PGRP_NULL) {
 pgsignal(struct pgrp *pgrp, int signum, int checkctty)
 {
        if (pgrp != PGRP_NULL) {

-               pgrp_iterate(pgrp, PGRP_BLOCKITERATE, pgsignal_callback, &signum, pgsignal_filt, &checkctty);
+               pgrp_iterate(pgrp, 0, pgsignal_callback, &signum, pgsignal_filt, &checkctty);

        }
 }
 
        }
 }
 


@@ -1613,7 +1941,7 @@ tty_pgsignal(struct tty *tp, int signum, int checkctty)
 
        pg = tty_pgrp(tp);
        if (pg != PGRP_NULL) {
 
        pg = tty_pgrp(tp);
        if (pg != PGRP_NULL) {

-               pgrp_iterate(pg, PGRP_BLOCKITERATE, pgsignal_callback, &signum, pgsignal_filt, &checkctty);
+               pgrp_iterate(pg, 0, pgsignal_callback, &signum, pgsignal_filt, &checkctty);

                pg_rele(pg);
        }
 }
                pg_rele(pg);
        }
 }


@@ -1621,25 +1949,28 @@ tty_pgsignal(struct tty *tp, int signum, int checkctty)
  * Send a signal caused by a trap to a specific thread.
  */
 void
  * Send a signal caused by a trap to a specific thread.
  */
 void

-threadsignal(thread_t sig_actthread, int signum, mach_exception_code_t code)
+threadsignal(thread_t sig_actthread, int signum, mach_exception_code_t code, boolean_t set_exitreason)

 {
        struct uthread *uth;
        struct task * sig_task;
        proc_t p;
        int mask;
 
 {
        struct uthread *uth;
        struct task * sig_task;
        proc_t p;
        int mask;
 

-       if ((u_int)signum >= NSIG || signum == 0)
+       if ((u_int)signum >= NSIG || signum == 0) {

                return;
                return;

+       }

 
        mask = sigmask(signum);
 
        mask = sigmask(signum);

-       if ((mask & threadmask) == 0)
+       if ((mask & threadmask) == 0) {

                return;
                return;

+       }

        sig_task = get_threadtask(sig_actthread);
        p = (proc_t)(get_bsdtask_info(sig_task));
 
        uth = get_bsdthread_info(sig_actthread);
        sig_task = get_threadtask(sig_actthread);
        p = (proc_t)(get_bsdtask_info(sig_task));
 
        uth = get_bsdthread_info(sig_actthread);

-       if (uth->uu_flag & UT_VFORK)
+       if (uth->uu_flag & UT_VFORK) {

                p = uth->uu_proc;
                p = uth->uu_proc;

+       }

 
        proc_lock(p);
        if (!(p->p_lflag & P_LTRACED) && (p->p_sigignore & mask)) {
 
        proc_lock(p);
        if (!(p->p_lflag & P_LTRACED) && (p->p_sigignore & mask)) {


@@ -1649,12 +1980,117 @@ threadsignal(thread_t sig_actthread, int signum, mach_exception_code_t code)
 
        uth->uu_siglist |= mask;
        uth->uu_code = code;
 
        uth->uu_siglist |= mask;
        uth->uu_code = code;

+
+       /* Attempt to establish whether the signal will be fatal (mirrors logic in psignal_internal()) */
+       if (set_exitreason && ((p->p_lflag & P_LTRACED) || (!(uth->uu_sigwait & mask)
+           && !(uth->uu_sigmask & mask) && !(p->p_sigcatch & mask))) &&
+           !(mask & stopsigmask) && !(mask & contsigmask)) {
+               if (uth->uu_exit_reason == OS_REASON_NULL) {
+                       KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+                           p->p_pid, OS_REASON_SIGNAL, signum, 0, 0);
+
+                       os_reason_t signal_reason = build_signal_reason(signum, "exc handler");
+
+                       set_thread_exit_reason(sig_actthread, signal_reason, TRUE);
+
+                       /* We dropped/consumed the reference in set_thread_exit_reason() */
+                       signal_reason = OS_REASON_NULL;
+               }
+       }
+

        proc_unlock(p);
 
        /* mark on process as well */
        signal_setast(sig_actthread);
 }
 
        proc_unlock(p);
 
        /* mark on process as well */
        signal_setast(sig_actthread);
 }
 

+/* Called with proc locked */
+static void
+set_thread_extra_flags(struct uthread *uth, os_reason_t reason)
+{
+       extern int vm_shared_region_reslide_restrict;
+       assert(uth != NULL);
+       /*
+        * Check whether the userland fault address falls within the shared
+        * region and notify userland if so. This allows launchd to apply
+        * special policies around this fault type.
+        */
+       if (reason->osr_namespace == OS_REASON_SIGNAL &&
+           reason->osr_code == SIGSEGV) {
+               mach_vm_address_t fault_address = uth->uu_subcode;
+
+#if defined(__arm64__)
+               /* taken from osfmk/arm/misc_protos.h */
+               #define TBI_MASK           0xff00000000000000
+               #define tbi_clear(addr)    ((addr) & ~(TBI_MASK))
+               fault_address = tbi_clear(fault_address);
+#endif /* __arm64__ */
+
+               if (fault_address >= SHARED_REGION_BASE &&
+                   fault_address <= SHARED_REGION_BASE + SHARED_REGION_SIZE) {
+                       /*
+                        * Always report whether the fault happened within the shared cache
+                        * region, but only stale the slide if the resliding is extended
+                        * to all processes or if the process faulting is a platform one.
+                        */
+                       reason->osr_flags |= OS_REASON_FLAG_SHAREDREGION_FAULT;
+
+#if __has_feature(ptrauth_calls)
+                       if (!vm_shared_region_reslide_restrict || csproc_get_platform_binary(current_proc())) {
+                               vm_shared_region_reslide_stale();
+                       }
+#endif /* __has_feature(ptrauth_calls) */
+               }
+       }
+}
+
+void
+set_thread_exit_reason(void *th, void *reason, boolean_t proc_locked)
+{
+       struct uthread *targ_uth = get_bsdthread_info(th);
+       struct task *targ_task = NULL;
+       proc_t targ_proc = NULL;
+
+       os_reason_t exit_reason = (os_reason_t)reason;
+
+       if (exit_reason == OS_REASON_NULL) {
+               return;
+       }
+
+       if (!proc_locked) {
+               targ_task = get_threadtask(th);
+               targ_proc = (proc_t)(get_bsdtask_info(targ_task));
+
+               proc_lock(targ_proc);
+       }
+
+       set_thread_extra_flags(targ_uth, exit_reason);
+
+       if (targ_uth->uu_exit_reason == OS_REASON_NULL) {
+               targ_uth->uu_exit_reason = exit_reason;
+       } else {
+               /* The caller expects that we drop a reference on the exit reason */
+               os_reason_free(exit_reason);
+       }
+
+       if (!proc_locked) {
+               assert(targ_proc != NULL);
+               proc_unlock(targ_proc);
+       }
+}
+
+/*
+ * get_signalthread
+ *
+ * Picks an appropriate thread from a process to target with a signal.
+ *
+ * Called with proc locked.
+ * Returns thread with BSD ast set.
+ *
+ * We attempt to deliver a proc-wide signal to the first thread in the task.
+ * This allows single threaded applications which use signals to
+ * be able to be linked with multithreaded libraries.
+ */

 static kern_return_t
 get_signalthread(proc_t p, int signum, thread_t * thr)
 {
 static kern_return_t
 get_signalthread(proc_t p, int signum, thread_t * thr)
 {


@@ -1663,36 +2099,102 @@ get_signalthread(proc_t p, int signum, thread_t * thr)
        thread_t sig_thread;
        struct task * sig_task = p->task;
        kern_return_t kret;
        thread_t sig_thread;
        struct task * sig_task = p->task;
        kern_return_t kret;

-       
+       bool skip_wqthreads = true;
+

        *thr = THREAD_NULL;
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
        *thr = THREAD_NULL;
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {

-               sig_thread = p->p_vforkact;     
+               sig_thread = p->p_vforkact;

                kret = check_actforsig(sig_task, sig_thread, 1);
                kret = check_actforsig(sig_task, sig_thread, 1);

-               if (kret == KERN_SUCCESS)  {
+               if (kret == KERN_SUCCESS) {

                        *thr = sig_thread;
                        *thr = sig_thread;

-                       return(KERN_SUCCESS);
-               }else
-                       return(KERN_FAILURE);
-       } 
+                       return KERN_SUCCESS;
+               } else {
+                       return KERN_FAILURE;
+               }
+       }

 
 

-       proc_lock(p);
+again:

        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {

-               if(((uth->uu_flag & UT_NO_SIGMASK)== 0) && 
-                       (((uth->uu_sigmask & mask) == 0) || (uth->uu_sigwait & mask))) {
-                       if (check_actforsig(p->task, uth->uu_context.vc_thread, 1) == KERN_SUCCESS) {
-                               *thr = uth->uu_context.vc_thread;
-                               proc_unlock(p);
-                               return(KERN_SUCCESS);
+               if (((uth->uu_flag & UT_NO_SIGMASK) == 0) &&
+                   (((uth->uu_sigmask & mask) == 0) || (uth->uu_sigwait & mask))) {
+                       thread_t th = uth->uu_context.vc_thread;
+                       if (skip_wqthreads && (thread_get_tag(th) & THREAD_TAG_WORKQUEUE)) {
+                               /* Workqueue threads may be parked in the kernel unable to
+                                * deliver signals for an extended period of time, so skip them
+                                * in favor of pthreads in a first pass. (rdar://50054475). */
+                       } else if (check_actforsig(p->task, th, 1) == KERN_SUCCESS) {
+                               *thr = th;
+                               return KERN_SUCCESS;

                        }
                }
                        }
                }

-       }
-       proc_unlock(p);
-       if (get_signalact(p->task, thr, 1) == KERN_SUCCESS) {
-               return(KERN_SUCCESS);
+       }
+       if (skip_wqthreads) {
+               skip_wqthreads = false;
+               goto again;
+       }
+       if (get_signalact(p->task, thr, 1) == KERN_SUCCESS) {
+               return KERN_SUCCESS;
+       }
+
+       return KERN_FAILURE;
+}
+
+static os_reason_t
+build_signal_reason(int signum, const char *procname)
+{
+       os_reason_t signal_reason = OS_REASON_NULL;
+       proc_t sender_proc = current_proc();
+       uint32_t reason_buffer_size_estimate = 0, proc_name_length = 0;
+       const char *default_sender_procname = "unknown";
+       mach_vm_address_t data_addr;
+       int ret;
+
+       signal_reason = os_reason_create(OS_REASON_SIGNAL, signum);
+       if (signal_reason == OS_REASON_NULL) {
+               printf("build_signal_reason: unable to allocate signal reason structure.\n");
+               return signal_reason;
+       }
+
+       reason_buffer_size_estimate = kcdata_estimate_required_buffer_size(2, sizeof(sender_proc->p_name) +
+           sizeof(sender_proc->p_pid));
+
+       ret = os_reason_alloc_buffer_noblock(signal_reason, reason_buffer_size_estimate);
+       if (ret != 0) {
+               printf("build_signal_reason: unable to allocate signal reason buffer.\n");
+               return signal_reason;
+       }
+
+       if (KERN_SUCCESS == kcdata_get_memory_addr(&signal_reason->osr_kcd_descriptor, KCDATA_TYPE_PID,
+           sizeof(sender_proc->p_pid), &data_addr)) {
+               kcdata_memcpy(&signal_reason->osr_kcd_descriptor, data_addr, &sender_proc->p_pid,
+                   sizeof(sender_proc->p_pid));
+       } else {
+               printf("build_signal_reason: exceeded space in signal reason buf, unable to log PID\n");
+       }
+
+       proc_name_length = sizeof(sender_proc->p_name);
+       if (KERN_SUCCESS == kcdata_get_memory_addr(&signal_reason->osr_kcd_descriptor, KCDATA_TYPE_PROCNAME,
+           proc_name_length, &data_addr)) {
+               if (procname) {
+                       char truncated_procname[proc_name_length];
+                       strncpy((char *) &truncated_procname, procname, proc_name_length);
+                       truncated_procname[proc_name_length - 1] = '\0';
+
+                       kcdata_memcpy(&signal_reason->osr_kcd_descriptor, data_addr, truncated_procname,
+                           (uint32_t)strlen((char *) &truncated_procname));
+               } else if (*sender_proc->p_name) {
+                       kcdata_memcpy(&signal_reason->osr_kcd_descriptor, data_addr, &sender_proc->p_name,
+                           sizeof(sender_proc->p_name));
+               } else {
+                       kcdata_memcpy(&signal_reason->osr_kcd_descriptor, data_addr, &default_sender_procname,
+                           (uint32_t)strlen(default_sender_procname) + 1);
+               }
+       } else {
+               printf("build_signal_reason: exceeded space in signal reason buf, unable to log procname\n");

        }
 
        }
 

-       return(KERN_FAILURE);
+       return signal_reason;

 }
 
 /*
 }
 
 /*


@@ -1700,6 +2202,9 @@ get_signalthread(proc_t p, int signum, thread_t * thr)
  * is usually performed by the target process rather than the caller; we add
  * the signal to the set of pending signals for the process.
  *
  * is usually performed by the target process rather than the caller; we add
  * the signal to the set of pending signals for the process.
  *

+ * Always drops a reference on a signal_reason if one is provided, whether via
+ * passing it to a thread or deallocating directly.
+ *

  * Exceptions:
  *   o When a stop signal is sent to a sleeping process that takes the
  *     default action, the process is stopped without awakening it.
  * Exceptions:
  *   o When a stop signal is sent to a sleeping process that takes the
  *     default action, the process is stopped without awakening it.


@@ -1709,31 +2214,51 @@ get_signalthread(proc_t p, int signum, thread_t * thr)
  * Other ignored signals are discarded immediately.
  */
 static void
  * Other ignored signals are discarded immediately.
  */
 static void

-psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
+psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum, os_reason_t signal_reason)

 {
        int prop;
 {
        int prop;

-       sig_t action = NULL;
-       proc_t          sig_proc;
-       thread_t        sig_thread;
-       register task_t         sig_task;
-       int mask;
-       struct uthread *uth;
-       kern_return_t kret;
-       uid_t r_uid;
-       proc_t pp;
-       kauth_cred_t my_cred;
+       user_addr_t action = USER_ADDR_NULL;
+       proc_t                  sig_proc;
+       thread_t                sig_thread;
+       task_t                  sig_task;
+       int                     mask;
+       struct uthread          *uth;
+       kern_return_t           kret;
+       uid_t                   r_uid;
+       proc_t                  pp;
+       kauth_cred_t            my_cred;
+       char                    *launchd_exit_reason_desc = NULL;
+       boolean_t               update_thread_policy = FALSE;
+
+       if ((u_int)signum >= NSIG || signum == 0) {
+               panic("psignal: bad signal number %d", signum);
+       }

 
 

-       if ((u_int)signum >= NSIG || signum == 0)
-               panic("psignal signal number");

        mask = sigmask(signum);
        prop = sigprop[signum];
 
 #if SIGNAL_DEBUG
        mask = sigmask(signum);
        prop = sigprop[signum];
 
 #if SIGNAL_DEBUG

-        if(rdebug_proc && (p != PROC_NULL) && (p == rdebug_proc)) {
-                ram_printf(3);
-        }
+       if (rdebug_proc && (p != PROC_NULL) && (p == rdebug_proc)) {
+               ram_printf(3);
+       }

 #endif /* SIGNAL_DEBUG */
 
 #endif /* SIGNAL_DEBUG */
 

+       /* catch unexpected initproc kills early for easier debuggging */
+       if (signum == SIGKILL && p == initproc) {
+               if (signal_reason == NULL) {
+                       panic_plain("unexpected SIGKILL of %s %s (no reason provided)",
+                           (p->p_name[0] != '\0' ? p->p_name : "initproc"),
+                           ((p->p_csflags & CS_KILLED) ? "(CS_KILLED)" : ""));
+               } else {
+                       launchd_exit_reason_desc = launchd_exit_reason_get_string_desc(signal_reason);
+                       panic_plain("unexpected SIGKILL of %s %s with reason -- namespace %d code 0x%llx description %." LAUNCHD_PANIC_REASON_STRING_MAXLEN "s",
+                           (p->p_name[0] != '\0' ? p->p_name : "initproc"),
+                           ((p->p_csflags & CS_KILLED) ? "(CS_KILLED)" : ""),
+                           signal_reason->osr_namespace, signal_reason->osr_code,
+                           launchd_exit_reason_desc ? launchd_exit_reason_desc : "none");
+               }
+       }
+

        /*
         *      We will need the task pointer later.  Grab it now to
         *      check for a zombie process.  Also don't send signals
        /*
         *      We will need the task pointer later.  Grab it now to
         *      check for a zombie process.  Also don't send signals


@@ -1747,14 +2272,21 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                sig_task = get_threadtask(thread);
                sig_thread = thread;
                sig_proc = (proc_t)get_bsdtask_info(sig_task);
                sig_task = get_threadtask(thread);
                sig_thread = thread;
                sig_proc = (proc_t)get_bsdtask_info(sig_task);

+       } else if (flavor & PSIG_TRY_THREAD) {
+               assert((thread == current_thread()) && (p == current_proc()));
+               sig_task = p->task;
+               sig_thread = thread;
+               sig_proc = p;

        } else {
                sig_task = p->task;
        } else {
                sig_task = p->task;

-               sig_thread = (struct thread *)0;
+               sig_thread = THREAD_NULL;

                sig_proc = p;
        }
 
                sig_proc = p;
        }
 

-       if ((sig_task == TASK_NULL) || is_kerneltask(sig_task))
+       if ((sig_task == TASK_NULL) || is_kerneltask(sig_task)) {
+               os_reason_free(signal_reason);

                return;
                return;

+       }

 
        /*
         * do not send signals to the process that has the thread
 
        /*
         * do not send signals to the process that has the thread


@@ -1763,37 +2295,50 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
         * also no need to send a signal to a process that is in the middle
         * of being torn down.
         */
         * also no need to send a signal to a process that is in the middle
         * of being torn down.
         */

-       if (ISSET(sig_proc->p_flag, P_REBOOT) ||
-           ISSET(sig_proc->p_lflag, P_LEXIT))
+       if (ISSET(sig_proc->p_flag, P_REBOOT) || ISSET(sig_proc->p_lflag, P_LEXIT)) {
+               DTRACE_PROC3(signal__discard, thread_t, sig_thread, proc_t, sig_proc, int, signum);
+               os_reason_free(signal_reason);

                return;
                return;

+       }

 
 

-       if( (flavor & (PSIG_VFORK | PSIG_THREAD)) == 0) {
+       if ((flavor & (PSIG_VFORK | PSIG_THREAD)) == 0) {

                proc_knote(sig_proc, NOTE_SIGNAL | signum);
        }
 
                proc_knote(sig_proc, NOTE_SIGNAL | signum);
        }
 

-       if ((flavor & PSIG_LOCKED)== 0)
+       if ((flavor & PSIG_LOCKED) == 0) {

                proc_signalstart(sig_proc, 0);
                proc_signalstart(sig_proc, 0);

+       }

 
 

-       /*
-        *      Deliver the signal to the first thread in the task. This
-        *      allows single threaded applications which use signals to
-        *      be able to be linked with multithreaded libraries.  We have
-        *      an implicit reference to the current thread, but need
-        *      an explicit one otherwise.  The thread reference keeps
-        *      the corresponding task data structures around too.  This
-        *      reference is released by thread_deallocate.
-        */
-       
-
+       /* Don't send signals to a process that has ignored them. */

        if (((flavor & PSIG_VFORK) == 0) && ((sig_proc->p_lflag & P_LTRACED) == 0) && (sig_proc->p_sigignore & mask)) {
                DTRACE_PROC3(signal__discard, thread_t, sig_thread, proc_t, sig_proc, int, signum);
        if (((flavor & PSIG_VFORK) == 0) && ((sig_proc->p_lflag & P_LTRACED) == 0) && (sig_proc->p_sigignore & mask)) {
                DTRACE_PROC3(signal__discard, thread_t, sig_thread, proc_t, sig_proc, int, signum);

-               goto psigout;
+               goto sigout_unlocked;

        }
 
        }
 

+       /*
+        * The proc_lock prevents the targeted thread from being deallocated
+        * or handling the signal until we're done signaling it.
+        *
+        * Once the proc_lock is dropped, we have no guarantee the thread or uthread exists anymore.
+        *
+        * XXX: What if the thread goes inactive after the thread passes bsd ast point?
+        */
+       proc_lock(sig_proc);
+

        if (flavor & PSIG_VFORK) {
                action = SIG_DFL;
                act_set_astbsd(sig_thread);
                kret = KERN_SUCCESS;
        if (flavor & PSIG_VFORK) {
                action = SIG_DFL;
                act_set_astbsd(sig_thread);
                kret = KERN_SUCCESS;

+       } else if (flavor & PSIG_TRY_THREAD) {
+               uth = get_bsdthread_info(sig_thread);
+               if (((uth->uu_flag & UT_NO_SIGMASK) == 0) &&
+                   (((uth->uu_sigmask & mask) == 0) || (uth->uu_sigwait & mask)) &&
+                   ((kret = check_actforsig(sig_proc->task, sig_thread, 1)) == KERN_SUCCESS)) {
+                       /* deliver to specified thread */
+               } else {
+                       /* deliver to any willing thread */
+                       kret = get_signalthread(sig_proc, signum, &sig_thread);
+               }

        } else if (flavor & PSIG_THREAD) {
                /* If successful return with ast set */
                kret = check_actforsig(sig_task, sig_thread, 1);
        } else if (flavor & PSIG_THREAD) {
                /* If successful return with ast set */
                kret = check_actforsig(sig_task, sig_thread, 1);


@@ -1801,14 +2346,13 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                /* If successful return with ast set */
                kret = get_signalthread(sig_proc, signum, &sig_thread);
        }
                /* If successful return with ast set */
                kret = get_signalthread(sig_proc, signum, &sig_thread);
        }

+

        if (kret != KERN_SUCCESS) {
        if (kret != KERN_SUCCESS) {

-#if SIGNAL_DEBUG
-                       ram_printf(1);
-#endif /* SIGNAL_DEBUG */
-               goto psigout;
+               DTRACE_PROC3(signal__discard, thread_t, sig_thread, proc_t, sig_proc, int, signum);
+               proc_unlock(sig_proc);
+               goto sigout_unlocked;

        }
 
        }
 

-

        uth = get_bsdthread_info(sig_thread);
 
        /*
        uth = get_bsdthread_info(sig_thread);
 
        /*


@@ -1816,9 +2360,9 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
         */
 
        if ((flavor & PSIG_VFORK) == 0) {
         */
 
        if ((flavor & PSIG_VFORK) == 0) {

-               if (sig_proc->p_lflag & P_LTRACED)
+               if (sig_proc->p_lflag & P_LTRACED) {

                        action = SIG_DFL;
                        action = SIG_DFL;

-               else {
+               } else {

                        /*
                         * If the signal is being ignored,
                         * then we forget about it immediately.
                        /*
                         * If the signal is being ignored,
                         * then we forget about it immediately.


@@ -1826,28 +2370,31 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                         * and if it is set to SIG_IGN,
                         * action will be SIG_DFL here.)
                         */
                         * and if it is set to SIG_IGN,
                         * action will be SIG_DFL here.)
                         */

-                       if (sig_proc->p_sigignore & mask)
-                               goto psigout;
-                       if (uth->uu_sigwait & mask)
+                       if (sig_proc->p_sigignore & mask) {
+                               goto sigout_locked;
+                       }
+
+                       if (uth->uu_sigwait & mask) {

                                action = KERN_SIG_WAIT;
                                action = KERN_SIG_WAIT;

-                       else if (uth->uu_sigmask & mask)
+                       } else if (uth->uu_sigmask & mask) {

                                action = KERN_SIG_HOLD;
                                action = KERN_SIG_HOLD;

-                       else if (sig_proc->p_sigcatch & mask)
+                       } else if (sig_proc->p_sigcatch & mask) {

                                action = KERN_SIG_CATCH;
                                action = KERN_SIG_CATCH;

-                       else
+                       } else {

                                action = SIG_DFL;
                                action = SIG_DFL;

+                       }

                }
        }
 
                }
        }
 

-
-       proc_lock(sig_proc);
-
+       /* TODO: p_nice isn't hooked up to the scheduler... */

        if (sig_proc->p_nice > NZERO && action == SIG_DFL && (prop & SA_KILL) &&
        if (sig_proc->p_nice > NZERO && action == SIG_DFL && (prop & SA_KILL) &&

-               (sig_proc->p_lflag & P_LTRACED) == 0)
-                       sig_proc->p_nice = NZERO;
+           (sig_proc->p_lflag & P_LTRACED) == 0) {
+               sig_proc->p_nice = NZERO;
+       }

 
 

-       if (prop & SA_CONT)
+       if (prop & SA_CONT) {

                uth->uu_siglist &= ~stopsigmask;
                uth->uu_siglist &= ~stopsigmask;

+       }

 
        if (prop & SA_STOP) {
                struct pgrp *pg;
 
        if (prop & SA_STOP) {
                struct pgrp *pg;


@@ -1857,41 +2404,34 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                 * is default; don't stop the process below if sleeping,
                 * and don't clear any pending SIGCONT.
                 */
                 * is default; don't stop the process below if sleeping,
                 * and don't clear any pending SIGCONT.
                 */

-               proc_unlock(sig_proc);

                pg = proc_pgrp(sig_proc);
                if (prop & SA_TTYSTOP && pg->pg_jobc == 0 &&
                pg = proc_pgrp(sig_proc);
                if (prop & SA_TTYSTOP && pg->pg_jobc == 0 &&

-                       action == SIG_DFL) {
+                   action == SIG_DFL) {

                        pg_rele(pg);
                        pg_rele(pg);

-                       goto psigout;
+                       goto sigout_locked;

                }
                pg_rele(pg);
                }
                pg_rele(pg);

-               proc_lock(sig_proc);

                uth->uu_siglist &= ~contsigmask;
        }
 
        uth->uu_siglist |= mask;
                uth->uu_siglist &= ~contsigmask;
        }
 
        uth->uu_siglist |= mask;

-       /* 
-        * Repost AST incase sigthread has processed 
-        * ast and missed signal post.
-        */
-       if (action == KERN_SIG_CATCH)
-               act_set_astbsd(sig_thread);

 
 

-       

        /*
         * Defer further processing for signals which are held,
         * except that stopped processes must be continued by SIGCONT.
         */
        /* vfork will not go thru as action is SIG_DFL */
        if ((action == KERN_SIG_HOLD) && ((prop & SA_CONT) == 0 || sig_proc->p_stat != SSTOP)) {
        /*
         * Defer further processing for signals which are held,
         * except that stopped processes must be continued by SIGCONT.
         */
        /* vfork will not go thru as action is SIG_DFL */
        if ((action == KERN_SIG_HOLD) && ((prop & SA_CONT) == 0 || sig_proc->p_stat != SSTOP)) {

-               proc_unlock(sig_proc);
-               goto psigout;
+               goto sigout_locked;

        }
        }

+

        /*
         *      SIGKILL priority twiddling moved here from above because
         *      it needs sig_thread.  Could merge it into large switch
         *      below if we didn't care about priority for tracing
         *      as SIGKILL's action is always SIG_DFL.
        /*
         *      SIGKILL priority twiddling moved here from above because
         *      it needs sig_thread.  Could merge it into large switch
         *      below if we didn't care about priority for tracing
         *      as SIGKILL's action is always SIG_DFL.

+        *
+        *      TODO: p_nice isn't hooked up to the scheduler...

         */
        if ((signum == SIGKILL) && (sig_proc->p_nice > NZERO)) {
                sig_proc->p_nice = NZERO;
         */
        if ((signum == SIGKILL) && (sig_proc->p_nice > NZERO)) {
                sig_proc->p_nice = NZERO;


@@ -1903,15 +2443,16 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
         *      issig() and stop for the parent.
         */
        if (sig_proc->p_lflag & P_LTRACED) {
         *      issig() and stop for the parent.
         */
        if (sig_proc->p_lflag & P_LTRACED) {

-               if (sig_proc->p_stat != SSTOP)
+               if (sig_proc->p_stat != SSTOP) {

                        goto runlocked;
                        goto runlocked;

-               else {
-                       proc_unlock(sig_proc);
-                       goto psigout;
+               } else {
+                       goto sigout_locked;

                }
        }
                }
        }

-       if ((flavor & PSIG_VFORK) != 0)
+
+       if ((flavor & PSIG_VFORK) != 0) {

                goto runlocked;
                goto runlocked;

+       }

 
        if (action == KERN_SIG_WAIT) {
 #if CONFIG_DTRACE
 
        if (action == KERN_SIG_WAIT) {
 #if CONFIG_DTRACE


@@ -1935,13 +2476,9 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                if (prop & SA_CONT) {
                        OSBitOrAtomic(P_CONTINUED, &sig_proc->p_flag);
                        sig_proc->p_contproc = current_proc()->p_pid;
                if (prop & SA_CONT) {
                        OSBitOrAtomic(P_CONTINUED, &sig_proc->p_flag);
                        sig_proc->p_contproc = current_proc()->p_pid;

-
-                       proc_unlock(sig_proc);

                        (void) task_resume_internal(sig_task);
                        (void) task_resume_internal(sig_task);

-                       goto psigout;

                }
                }

-               proc_unlock(sig_proc);
-               goto psigout;
+               goto sigout_locked;

        }
 
        if (action != SIG_DFL) {
        }
 
        if (action != SIG_DFL) {


@@ -1952,13 +2489,10 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                 */
                if (prop & SA_CONT) {
                        OSBitOrAtomic(P_CONTINUED, &sig_proc->p_flag);
                 */
                if (prop & SA_CONT) {
                        OSBitOrAtomic(P_CONTINUED, &sig_proc->p_flag);

-                       proc_unlock(sig_proc);

                        (void) task_resume_internal(sig_task);
                        (void) task_resume_internal(sig_task);

-                       proc_lock(sig_proc);

                        sig_proc->p_stat = SRUN;
                        sig_proc->p_stat = SRUN;

-               }  else if (sig_proc->p_stat == SSTOP) {
-                       proc_unlock(sig_proc);
-                       goto psigout;
+               } else if (sig_proc->p_stat == SSTOP) {
+                       goto sigout_locked;

                }
                /*
                 * Fill out siginfo structure information to pass to the
                }
                /*
                 * Fill out siginfo structure information to pass to the


@@ -1973,9 +2507,7 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                 * Note:        Avoid the SIGCHLD recursion case!
                 */
                if (signum != SIGCHLD) {
                 * Note:        Avoid the SIGCHLD recursion case!
                 */
                if (signum != SIGCHLD) {

-                       proc_unlock(sig_proc);

                        r_uid = kauth_getruid();
                        r_uid = kauth_getruid();

-                       proc_lock(sig_proc);

 
                        sig_proc->si_pid = current_proc()->p_pid;
                        sig_proc->si_status = W_EXITCODE(signum, 0);
 
                        sig_proc->si_pid = current_proc()->p_pid;
                        sig_proc->si_status = W_EXITCODE(signum, 0);


@@ -1987,6 +2519,7 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
        } else {
                /*      Default action - varies */
                if (mask & stopsigmask) {
        } else {
                /*      Default action - varies */
                if (mask & stopsigmask) {

+                       assert(signal_reason == NULL);

                        /*
                         * These are the signals which by default
                         * stop a process.
                        /*
                         * These are the signals which by default
                         * stop a process.


@@ -1995,14 +2528,13 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                         * stopped from the keyboard.
                         */
                        if (!(prop & SA_STOP) && sig_proc->p_pptr == initproc) {
                         * stopped from the keyboard.
                         */
                        if (!(prop & SA_STOP) && sig_proc->p_pptr == initproc) {

-                               proc_unlock(sig_proc);
-                               psignal_locked(sig_proc, SIGKILL);
-                               proc_lock(sig_proc);

                                uth->uu_siglist &= ~mask;
                                proc_unlock(sig_proc);
                                uth->uu_siglist &= ~mask;
                                proc_unlock(sig_proc);

-                               goto psigout;
+                               /* siglock still locked, proc_lock not locked */
+                               psignal_locked(sig_proc, SIGKILL);
+                               goto sigout_unlocked;

                        }
                        }

-                        
+

                        /*
                         *      Stop the task
                         *      if task hasn't already been stopped by
                        /*
                         *      Stop the task
                         *      if task hasn't already been stopped by


@@ -2018,8 +2550,7 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
 
                                pp = proc_parentholdref(sig_proc);
                                stop(sig_proc, pp);
 
                                pp = proc_parentholdref(sig_proc);
                                stop(sig_proc, pp);

-                               if (( pp != PROC_NULL) && ((pp->p_flag & P_NOCLDSTOP) == 0)) {
-
+                               if ((pp != PROC_NULL) && ((pp->p_flag & P_NOCLDSTOP) == 0)) {

                                        my_cred = kauth_cred_proc_ref(sig_proc);
                                        r_uid = kauth_cred_getruid(my_cred);
                                        kauth_cred_unref(&my_cred);
                                        my_cred = kauth_cred_proc_ref(sig_proc);
                                        r_uid = kauth_cred_getruid(my_cred);
                                        kauth_cred_unref(&my_cred);


@@ -2031,35 +2562,35 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                                         * when sent to the parent must set the
                                         * child's signal number into si_status.
                                         */
                                         * when sent to the parent must set the
                                         * child's signal number into si_status.
                                         */

-                                       if (signum != SIGSTOP)
+                                       if (signum != SIGSTOP) {

                                                pp->si_status = WEXITSTATUS(sig_proc->p_xstat);
                                                pp->si_status = WEXITSTATUS(sig_proc->p_xstat);

-                                       else
+                                       } else {

                                                pp->si_status = W_EXITCODE(signum, signum);
                                                pp->si_status = W_EXITCODE(signum, signum);

+                                       }

                                        pp->si_code = CLD_STOPPED;
                                        pp->si_uid = r_uid;
                                        proc_unlock(sig_proc);
 
                                        psignal(pp, SIGCHLD);
                                }
                                        pp->si_code = CLD_STOPPED;
                                        pp->si_uid = r_uid;
                                        proc_unlock(sig_proc);
 
                                        psignal(pp, SIGCHLD);
                                }

-                               if (pp != PROC_NULL)
+                               if (pp != PROC_NULL) {

                                        proc_parentdropref(pp, 0);
                                        proc_parentdropref(pp, 0);

-                       } else
-                               proc_unlock(sig_proc);
-                       goto psigout;
+                               }
+
+                               goto sigout_unlocked;
+                       }
+
+                       goto sigout_locked;

                }
 
                DTRACE_PROC3(signal__send, thread_t, sig_thread, proc_t, p, int, signum);
 
                }
 
                DTRACE_PROC3(signal__send, thread_t, sig_thread, proc_t, p, int, signum);
 

+               switch (signum) {

                /*
                /*

-                * enters switch with sig_proc lock held but dropped when
-                * gets out of switch
+                * Signals ignored by default have been dealt
+                * with already, since their bits are on in
+                * p_sigignore.

                 */
                 */

-               switch (signum) {
-                       /*
-                        * Signals ignored by default have been dealt
-                        * with already, since their bits are on in
-                        * p_sigignore.
-                        */

 
                case SIGKILL:
                        /*
 
                case SIGKILL:
                        /*


@@ -2078,22 +2609,35 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                         * We would need to cover this approp down the line.
                         */
                        act_set_astbsd(sig_thread);
                         * We would need to cover this approp down the line.
                         */
                        act_set_astbsd(sig_thread);

-                       thread_abort(sig_thread);
-                       proc_unlock(sig_proc);
+                       kret = thread_abort(sig_thread);
+                       update_thread_policy = (kret == KERN_SUCCESS);
+
+                       if (uth->uu_exit_reason == OS_REASON_NULL) {
+                               if (signal_reason == OS_REASON_NULL) {
+                                       KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+                                           sig_proc->p_pid, OS_REASON_SIGNAL, signum, 0, 0);

 
 

-                       goto psigout;
+                                       signal_reason = build_signal_reason(signum, NULL);
+                               }
+
+                               os_reason_ref(signal_reason);
+                               set_thread_exit_reason(sig_thread, signal_reason, TRUE);
+                       }
+
+                       goto sigout_locked;

 
                case SIGCONT:
                        /*
                         * Let the process run.  If it's sleeping on an
                         * event, it remains so.
                         */
 
                case SIGCONT:
                        /*
                         * Let the process run.  If it's sleeping on an
                         * event, it remains so.
                         */

+                       assert(signal_reason == NULL);

                        OSBitOrAtomic(P_CONTINUED, &sig_proc->p_flag);
                        sig_proc->p_contproc = sig_proc->p_pid;
                        OSBitOrAtomic(P_CONTINUED, &sig_proc->p_flag);
                        sig_proc->p_contproc = sig_proc->p_pid;

+                       sig_proc->p_xstat = signum;

 
 

-                       proc_unlock(sig_proc);

                        (void) task_resume_internal(sig_task);
                        (void) task_resume_internal(sig_task);

-                       proc_lock(sig_proc);
+

                        /*
                         * When processing a SIGCONT, we need to check
                         * to see if there are signals pending that
                        /*
                         * When processing a SIGCONT, we need to check
                         * to see if there are signals pending that


@@ -2104,7 +2648,7 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                         * cause their handlers to fire.  If it's only
                         * the SIGCONT, then don't wake up.
                         */
                         * cause their handlers to fire.  If it's only
                         * the SIGCONT, then don't wake up.
                         */

-                       if (((flavor & (PSIG_VFORK|PSIG_THREAD)) == 0) && (((uth->uu_siglist & ~uth->uu_sigmask) & ~sig_proc->p_sigignore) & ~mask)) {
+                       if (((flavor & (PSIG_VFORK | PSIG_THREAD)) == 0) && (((uth->uu_siglist & ~uth->uu_sigmask) & ~sig_proc->p_sigignore) & ~mask)) {

                                uth->uu_siglist &= ~mask;
                                sig_proc->p_stat = SRUN;
                                goto runlocked;
                                uth->uu_siglist &= ~mask;
                                sig_proc->p_stat = SRUN;
                                goto runlocked;


@@ -2112,8 +2656,7 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
 
                        uth->uu_siglist &= ~mask;
                        sig_proc->p_stat = SRUN;
 
                        uth->uu_siglist &= ~mask;
                        sig_proc->p_stat = SRUN;

-                       proc_unlock(sig_proc);
-                       goto psigout;
+                       goto sigout_locked;

 
                default:
                        /*
 
                default:
                        /*


@@ -2121,11 +2664,24 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                         * the process, and for which there is no handler,
                         * needs to act like SIGKILL
                         */
                         * the process, and for which there is no handler,
                         * needs to act like SIGKILL
                         */

-                       if (((flavor & (PSIG_VFORK|PSIG_THREAD)) == 0) && (action == SIG_DFL) && (prop & SA_KILL)) {
+                       if (((flavor & (PSIG_VFORK | PSIG_THREAD)) == 0) && (action == SIG_DFL) && (prop & SA_KILL)) {

                                sig_proc->p_stat = SRUN;
                                sig_proc->p_stat = SRUN;

-                               proc_unlock(sig_proc);
-                               thread_abort(sig_thread);
-                               goto psigout;
+                               kret = thread_abort(sig_thread);
+                               update_thread_policy = (kret == KERN_SUCCESS);
+
+                               if (uth->uu_exit_reason == OS_REASON_NULL) {
+                                       if (signal_reason == OS_REASON_NULL) {
+                                               KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+                                                   sig_proc->p_pid, OS_REASON_SIGNAL, signum, 0, 0);
+
+                                               signal_reason = build_signal_reason(signum, NULL);
+                                       }
+
+                                       os_reason_ref(signal_reason);
+                                       set_thread_exit_reason(sig_thread, signal_reason, TRUE);
+                               }
+
+                               goto sigout_locked;

                        }
 
                        /*
                        }
 
                        /*


@@ -2133,8 +2689,7 @@ psignal_internal(proc_t p, task_t task, thread_t thread, int flavor, int signum)
                         * resume it.
                         */
                        if (sig_proc->p_stat == SSTOP) {
                         * resume it.
                         */
                        if (sig_proc->p_stat == SSTOP) {

-                               proc_unlock(sig_proc);
-                               goto psigout;
+                               goto sigout_locked;

                        }
                        goto runlocked;
                }
                        }
                        goto runlocked;
                }


@@ -2147,24 +2702,39 @@ runlocked:
         * while we were stopped), check for a signal from the debugger.
         */
        if (sig_proc->p_stat == SSTOP) {
         * while we were stopped), check for a signal from the debugger.
         */
        if (sig_proc->p_stat == SSTOP) {

-               if ((sig_proc->p_lflag & P_LTRACED) != 0 && sig_proc->p_xstat != 0)
-                       uth->uu_siglist |= sigmask(sig_proc->p_xstat); 
+               if ((sig_proc->p_lflag & P_LTRACED) != 0 && sig_proc->p_xstat != 0) {
+                       uth->uu_siglist |= sigmask(sig_proc->p_xstat);
+               }
+

                if ((flavor & PSIG_VFORK) != 0) {
                        sig_proc->p_stat = SRUN;
                }
                if ((flavor & PSIG_VFORK) != 0) {
                        sig_proc->p_stat = SRUN;
                }

-               proc_unlock(sig_proc);  

        } else {
                /*
        } else {
                /*

-                * setrunnable(p) in BSD and
-                * Wake up the thread if it is interruptible.
-                */
+                * setrunnable(p) in BSD and
+                * Wake up the thread if it is interruptible.
+                */

                sig_proc->p_stat = SRUN;
                sig_proc->p_stat = SRUN;

-               proc_unlock(sig_proc);  
-               if ((flavor & PSIG_VFORK) == 0)
+               if ((flavor & PSIG_VFORK) == 0) {

                        thread_abort_safely(sig_thread);
                        thread_abort_safely(sig_thread);

+               }
+       }
+
+sigout_locked:
+       if (update_thread_policy) {
+               /*
+                * Update the thread policy to heading to terminate, increase priority if
+                * necessary. This needs to be done before we drop the proc lock because the
+                * thread can take the fatal signal once it's dropped.
+                */
+               proc_set_thread_policy(sig_thread, TASK_POLICY_ATTRIBUTE, TASK_POLICY_TERMINATED, TASK_POLICY_ENABLE);

        }
        }

-psigout:
-       if ((flavor & PSIG_LOCKED)== 0) {
+
+       proc_unlock(sig_proc);
+
+sigout_unlocked:
+       os_reason_free(signal_reason);
+       if ((flavor & PSIG_LOCKED) == 0) {

                proc_signalend(sig_proc, 0);
        }
 }
                proc_signalend(sig_proc, 0);
        }
 }


@@ -2172,27 +2742,64 @@ psigout:
 void
 psignal(proc_t p, int signum)
 {
 void
 psignal(proc_t p, int signum)
 {

-       psignal_internal(p, NULL, NULL, 0, signum);
+       psignal_internal(p, NULL, NULL, 0, signum, NULL);
+}
+
+void
+psignal_with_reason(proc_t p, int signum, struct os_reason *signal_reason)
+{
+       psignal_internal(p, NULL, NULL, 0, signum, signal_reason);
+}
+
+void
+psignal_sigkill_with_reason(struct proc *p, struct os_reason *signal_reason)
+{
+       psignal_internal(p, NULL, NULL, 0, SIGKILL, signal_reason);

 }
 
 void
 psignal_locked(proc_t p, int signum)
 {
 }
 
 void
 psignal_locked(proc_t p, int signum)
 {

-       psignal_internal(p, NULL, NULL, PSIG_LOCKED, signum);
+       psignal_internal(p, NULL, NULL, PSIG_LOCKED, signum, NULL);
+}
+
+void
+psignal_vfork_with_reason(proc_t p, task_t new_task, thread_t thread, int signum, struct os_reason *signal_reason)
+{
+       psignal_internal(p, new_task, thread, PSIG_VFORK, signum, signal_reason);

 }
 
 }
 

+

 void
 psignal_vfork(proc_t p, task_t new_task, thread_t thread, int signum)
 {
 void
 psignal_vfork(proc_t p, task_t new_task, thread_t thread, int signum)
 {

-       psignal_internal(p, new_task, thread, PSIG_VFORK, signum);
+       psignal_internal(p, new_task, thread, PSIG_VFORK, signum, NULL);

 }
 
 }
 

-static void
+void

 psignal_uthread(thread_t thread, int signum)
 {
 psignal_uthread(thread_t thread, int signum)
 {

-       psignal_internal(PROC_NULL, TASK_NULL, thread, PSIG_THREAD, signum);
+       psignal_internal(PROC_NULL, TASK_NULL, thread, PSIG_THREAD, signum, NULL);
+}
+
+/* same as psignal(), but prefer delivery to 'thread' if possible */
+void
+psignal_try_thread(proc_t p, thread_t thread, int signum)
+{
+       psignal_internal(p, NULL, thread, PSIG_TRY_THREAD, signum, NULL);
+}
+
+void
+psignal_try_thread_with_reason(proc_t p, thread_t thread, int signum, struct os_reason *signal_reason)
+{
+       psignal_internal(p, TASK_NULL, thread, PSIG_TRY_THREAD, signum, signal_reason);

 }
 
 }
 

+void
+psignal_thread_with_reason(proc_t p, thread_t thread, int signum, struct os_reason *signal_reason)
+{
+       psignal_internal(p, TASK_NULL, thread, PSIG_THREAD, signum, signal_reason);
+}

 
 /*
  * If the current process has received a signal (should be caught or cause
 
 /*
  * If the current process has received a signal (should be caught or cause


@@ -2220,32 +2827,33 @@ issignal_locked(proc_t p)
        cur_act = current_thread();
 
 #if SIGNAL_DEBUG
        cur_act = current_thread();
 
 #if SIGNAL_DEBUG

-        if(rdebug_proc && (p == rdebug_proc)) {
-                ram_printf(3);
-        }
+       if (rdebug_proc && (p == rdebug_proc)) {
+               ram_printf(3);
+       }

 #endif /* SIGNAL_DEBUG */
 
        /*
         * Try to grab the signal lock.
         */
        if (sig_try_locked(p) <= 0) {
 #endif /* SIGNAL_DEBUG */
 
        /*
         * Try to grab the signal lock.
         */
        if (sig_try_locked(p) <= 0) {

-               return(0);
+               return 0;

        }
 
        proc_signalstart(p, 1);
 
        ut = get_bsdthread_info(cur_act);
        }
 
        proc_signalstart(p, 1);
 
        ut = get_bsdthread_info(cur_act);

-       for(;;) {
-               sigbits = ut->uu_siglist  & ~ut->uu_sigmask;
+       for (;;) {
+               sigbits = ut->uu_siglist & ~ut->uu_sigmask;

 
 

-               if (p->p_lflag & P_LPPWAIT)
+               if (p->p_lflag & P_LPPWAIT) {

                        sigbits &= ~stopsigmask;
                        sigbits &= ~stopsigmask;

-               if (sigbits == 0) {             /* no signal to send */
+               }
+               if (sigbits == 0) {             /* no signal to send */

                        retval = 0;
                        goto out;
                }
 
                        retval = 0;
                        goto out;
                }
 

-               signum = ffs((long)sigbits);
+               signum = ffs((unsigned int)sigbits);

                mask = sigmask(signum);
                prop = sigprop[signum];
 
                mask = sigmask(signum);
                prop = sigprop[signum];
 


@@ -2254,25 +2862,25 @@ issignal_locked(proc_t p)
                 * only if P_LTRACED was on when they were posted.
                 */
                if (mask & p->p_sigignore && (p->p_lflag & P_LTRACED) == 0) {
                 * only if P_LTRACED was on when they were posted.
                 */
                if (mask & p->p_sigignore && (p->p_lflag & P_LTRACED) == 0) {

-                       ut->uu_siglist &= ~mask;                /* take the signal! */
+                       ut->uu_siglist &= ~mask;

                        continue;
                }
                        continue;
                }

-               if (p->p_lflag & P_LTRACED && (p->p_lflag & P_LPPWAIT) == 0)  {
-                       task_t  task;
+
+               if (p->p_lflag & P_LTRACED && (p->p_lflag & P_LPPWAIT) == 0) {

                        /*
                        /*

-                        * If traced, always stop, and stay
-                        * stopped until released by the debugger.
+                        * If traced, deliver the signal to the debugger, and wait to be
+                        * released.

                         */
                         */

-                       /* ptrace debugging */
+                       task_t  task;

                        p->p_xstat = signum;
                        p->p_xstat = signum;

-       
+

                        if (p->p_lflag & P_LSIGEXC) {
                                p->sigwait = TRUE;
                                p->sigwait_thread = cur_act;
                                p->p_stat = SSTOP;
                                OSBitAndAtomic(~((uint32_t)P_CONTINUED), &p->p_flag);
                                p->p_lflag &= ~P_LWAITED;
                        if (p->p_lflag & P_LSIGEXC) {
                                p->sigwait = TRUE;
                                p->sigwait_thread = cur_act;
                                p->p_stat = SSTOP;
                                OSBitAndAtomic(~((uint32_t)P_CONTINUED), &p->p_flag);
                                p->p_lflag &= ~P_LWAITED;

-                               ut->uu_siglist &= ~mask;        /* clear the old signal */
+                               ut->uu_siglist &= ~mask; /* clear the current signal from the pending list */

                                proc_signalend(p, 1);
                                proc_unlock(p);
                                do_bsdexception(EXC_SOFTWARE, EXC_SOFT_SIGNAL, signum);
                                proc_signalend(p, 1);
                                proc_unlock(p);
                                do_bsdexception(EXC_SOFTWARE, EXC_SOFT_SIGNAL, signum);


@@ -2289,6 +2897,8 @@ issignal_locked(proc_t p)
                                        proc_lock(pp);
 
                                        pp->si_pid = p->p_pid;
                                        proc_lock(pp);
 
                                        pp->si_pid = p->p_pid;

+                                       pp->p_xhighbits = p->p_xhighbits;
+                                       p->p_xhighbits = 0;

                                        pp->si_status = p->p_xstat;
                                        pp->si_code = CLD_TRAPPED;
                                        pp->si_uid = r_uid;
                                        pp->si_status = p->p_xstat;
                                        pp->si_code = CLD_TRAPPED;
                                        pp->si_uid = r_uid;


@@ -2297,9 +2907,9 @@ issignal_locked(proc_t p)
                                }
 
                                /*
                                }
 
                                /*

-                               *       XXX Have to really stop for debuggers;
-                               *       XXX stop() doesn't do the right thing.
-                               */
+                                *      XXX Have to really stop for debuggers;
+                                *      XXX stop() doesn't do the right thing.
+                                */

                                task = p->task;
                                task_suspend_internal(task);
 
                                task = p->task;
                                task_suspend_internal(task);
 


@@ -2309,7 +2919,7 @@ issignal_locked(proc_t p)
                                p->p_stat = SSTOP;
                                OSBitAndAtomic(~((uint32_t)P_CONTINUED), &p->p_flag);
                                p->p_lflag &= ~P_LWAITED;
                                p->p_stat = SSTOP;
                                OSBitAndAtomic(~((uint32_t)P_CONTINUED), &p->p_flag);
                                p->p_lflag &= ~P_LWAITED;

-                               ut->uu_siglist &= ~mask;        /* clear the old signal */
+                               ut->uu_siglist &= ~mask;

 
                                proc_signalend(p, 1);
                                proc_unlock(p);
 
                                proc_signalend(p, 1);
                                proc_unlock(p);


@@ -2332,59 +2942,41 @@ issignal_locked(proc_t p)
                        p->sigwait_thread = NULL;
                        wakeup((caddr_t)&p->sigwait_thread);
 
                        p->sigwait_thread = NULL;
                        wakeup((caddr_t)&p->sigwait_thread);
 

-                       /*
-                        * This code is to detect when gdb is killed
-                        * even as the traced program is attached.
-                        * pgsignal would get the SIGKILL to traced program
-                        * That's what we are trying to see (I hope)
-                        */
-                       if (ut->uu_siglist & sigmask(SIGKILL)) {
+                       if (signum == SIGKILL || ut->uu_siglist & sigmask(SIGKILL)) {

                                /*
                                /*

-                                * Wait event may still be outstanding;
-                                * clear it, since sig_lock_to_exit will
-                                * wait.
+                                * Deliver a pending sigkill even if it's not the current signal.
+                                * Necessary for PT_KILL, which should not be delivered to the
+                                * debugger, but we can't differentiate it from any other KILL.

                                 */
                                 */

-                               clear_wait(current_thread(), THREAD_INTERRUPTED);
-                               sig_lock_to_exit(p);
-                               /*
-                               * Since this thread will be resumed
-                               * to allow the current syscall to
-                               * be completed, must save u_qsave
-                               * before calling exit().  (Since exit()
-                               * calls closef() which can trash u_qsave.)
-                               */
-                               proc_signalend(p, 1);
-                               proc_unlock(p);
-                               KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_FRCEXIT) | DBG_FUNC_NONE,
-                                             p->p_pid, W_EXITCODE(0, SIGKILL), 2, 0, 0);
-                               exit1(p, W_EXITCODE(0, SIGKILL), (int *)NULL);
-                               proc_lock(p);
-                               return(0);
+                               signum = SIGKILL;
+                               goto deliver_sig;

                        }
 
                        }
 

-                       /*
-                        *      We may have to quit
-                        */
+                       /* We may have to quit. */

                        if (thread_should_abort(current_thread())) {
                                retval = 0;
                                goto out;
                        }
                        if (thread_should_abort(current_thread())) {
                                retval = 0;
                                goto out;
                        }

+

                        /*
                         * If parent wants us to take the signal,
                         * then it will leave it in p->p_xstat;
                         * otherwise we just look for signals again.
                         */
                        signum = p->p_xstat;
                        /*
                         * If parent wants us to take the signal,
                         * then it will leave it in p->p_xstat;
                         * otherwise we just look for signals again.
                         */
                        signum = p->p_xstat;

-                       if (signum == 0)
+                       if (signum == 0) {

                                continue;
                                continue;

+                       }
+

                        /*
                         * Put the new signal into p_siglist.  If the
                         * signal is being masked, look for other signals.
                         */
                        mask = sigmask(signum);
                        ut->uu_siglist |= mask;
                        /*
                         * Put the new signal into p_siglist.  If the
                         * signal is being masked, look for other signals.
                         */
                        mask = sigmask(signum);
                        ut->uu_siglist |= mask;

-                       if (ut->uu_sigmask & mask)
+                       if (ut->uu_sigmask & mask) {

                                continue;
                                continue;

+                       }

                }
 
                /*
                }
 
                /*


@@ -2394,23 +2986,7 @@ issignal_locked(proc_t p)
                 */
 
                switch ((long)p->p_sigacts->ps_sigact[signum]) {
                 */
 
                switch ((long)p->p_sigacts->ps_sigact[signum]) {

-               

                case (long)SIG_DFL:
                case (long)SIG_DFL:

-                       /*
-                        * Don't take default actions on system processes.
-                        */
-                       if (p->p_ppid == 0) {
-#if DIAGNOSTIC
-                               /*
-                                * Are you sure you want to ignore SIGSEGV
-                                * in init? XXX
-                                */
-                               printf("Process (pid %d) got signal %d\n",
-                                       p->p_pid, signum);
-#endif
-                               break;                          /* == ignore */
-                       }
-                       

                        /*
                         * If there is a pending stop signal to process
                         * with default action, stop here,
                        /*
                         * If there is a pending stop signal to process
                         * with default action, stop here,


@@ -2424,17 +3000,16 @@ issignal_locked(proc_t p)
                                proc_unlock(p);
                                pg = proc_pgrp(p);
                                if (p->p_lflag & P_LTRACED ||
                                proc_unlock(p);
                                pg = proc_pgrp(p);
                                if (p->p_lflag & P_LTRACED ||

-                                       (pg->pg_jobc == 0 &&
-                                       prop & SA_TTYSTOP)) {
+                                   (pg->pg_jobc == 0 &&
+                                   prop & SA_TTYSTOP)) {

                                        proc_lock(p);
                                        pg_rele(pg);
                                        proc_lock(p);
                                        pg_rele(pg);

-                                       break;  /* == ignore */
+                                       break; /* ignore signal */

                                }
                                pg_rele(pg);
                                if (p->p_stat != SSTOP) {
                                        proc_lock(p);
                                        p->p_xstat = signum;
                                }
                                pg_rele(pg);
                                if (p->p_stat != SSTOP) {
                                        proc_lock(p);
                                        p->p_xstat = signum;

-                               

                                        p->p_stat = SSTOP;
                                        p->p_lflag &= ~P_LWAITED;
                                        proc_unlock(p);
                                        p->p_stat = SSTOP;
                                        p->p_lflag &= ~P_LWAITED;
                                        proc_unlock(p);


@@ -2455,8 +3030,9 @@ issignal_locked(proc_t p)
 
                                                psignal(pp, SIGCHLD);
                                        }
 
                                                psignal(pp, SIGCHLD);
                                        }

-                                       if (pp != PROC_NULL)
+                                       if (pp != PROC_NULL) {

                                                proc_parentdropref(pp, 0);
                                                proc_parentdropref(pp, 0);

+                                       }

                                }
                                proc_lock(p);
                                break;
                                }
                                proc_lock(p);
                                break;


@@ -2465,16 +3041,11 @@ issignal_locked(proc_t p)
                                 * Except for SIGCONT, shouldn't get here.
                                 * Default action is to ignore; drop it.
                                 */
                                 * Except for SIGCONT, shouldn't get here.
                                 * Default action is to ignore; drop it.
                                 */

-                               break;          /* == ignore */
+                               break; /* ignore signal */

                        } else {
                        } else {

-                               ut->uu_siglist &= ~mask;        /* take the signal! */
-                               retval = signum;
-                               goto out;
+                               goto deliver_sig;

                        }
 
                        }
 

-                       /*NOTREACHED*/
-                       break;
-

                case (long)SIG_IGN:
                        /*
                         * Masking above should prevent us ever trying
                case (long)SIG_IGN:
                        /*
                         * Masking above should prevent us ever trying


@@ -2482,25 +3053,29 @@ issignal_locked(proc_t p)
                         * than SIGCONT, unless process is traced.
                         */
                        if ((prop & SA_CONT) == 0 &&
                         * than SIGCONT, unless process is traced.
                         */
                        if ((prop & SA_CONT) == 0 &&

-                               (p->p_lflag & P_LTRACED) == 0)
+                           (p->p_lflag & P_LTRACED) == 0) {

                                printf("issignal\n");
                                printf("issignal\n");

-                       break;          /* == ignore */
+                       }
+                       break; /* ignore signal */

 
                default:
 
                default:

-                       /*
-                        * This signal has an action, let
-                        * postsig() process it.
-                        */
-                       ut->uu_siglist &= ~mask;                /* take the signal! */
-                       retval = signum;
-                       goto out;
-               }
-               ut->uu_siglist &= ~mask;                /* take the signal! */
+                       /* This signal has an action - deliver it. */
+                       goto deliver_sig;

                }
                }

+
+               /* If we dropped through, the signal was ignored - remove it from pending list. */
+               ut->uu_siglist &= ~mask;
+       } /* for(;;) */
+

        /* NOTREACHED */
        /* NOTREACHED */

+
+deliver_sig:
+       ut->uu_siglist &= ~mask;
+       retval = signum;
+

 out:
        proc_signalend(p, 1);
 out:
        proc_signalend(p, 1);

-       return(retval);
+       return retval;

 }
 
 /* called from _sleep */
 }
 
 /* called from _sleep */


@@ -2511,31 +3086,34 @@ CURSIG(proc_t p)
        thread_t cur_act;
        struct uthread * ut;
        int retnum = 0;
        thread_t cur_act;
        struct uthread * ut;
        int retnum = 0;

-           
+

 
        cur_act = current_thread();
 
        ut = get_bsdthread_info(cur_act);
 
 
        cur_act = current_thread();
 
        ut = get_bsdthread_info(cur_act);
 

-       if (ut->uu_siglist == 0)
-               return (0);
+       if (ut->uu_siglist == 0) {
+               return 0;
+       }

 
 

-       if (((ut->uu_siglist & ~ut->uu_sigmask) == 0) && ((p->p_lflag & P_LTRACED) == 0))
-               return (0);
+       if (((ut->uu_siglist & ~ut->uu_sigmask) == 0) && ((p->p_lflag & P_LTRACED) == 0)) {
+               return 0;
+       }

 
        sigbits = ut->uu_siglist & ~ut->uu_sigmask;
 
 
        sigbits = ut->uu_siglist & ~ut->uu_sigmask;
 

-       for(;;) {
-               if (p->p_lflag & P_LPPWAIT)
+       for (;;) {
+               if (p->p_lflag & P_LPPWAIT) {

                        sigbits &= ~stopsigmask;
                        sigbits &= ~stopsigmask;

-               if (sigbits == 0) {             /* no signal to send */
-                       return (retnum);
+               }
+               if (sigbits == 0) {             /* no signal to send */
+                       return retnum;

                }
 
                }
 

-               signum = ffs((long)sigbits);
+               signum = ffs((unsigned int)sigbits);

                mask = sigmask(signum);
                prop = sigprop[signum];
                mask = sigmask(signum);
                prop = sigprop[signum];

-               sigbits &= ~mask;               /* take the signal out */
+               sigbits &= ~mask;               /* take the signal out */

 
                /*
                 * We should see pending but ignored signals
 
                /*
                 * We should see pending but ignored signals


@@ -2546,7 +3124,7 @@ CURSIG(proc_t p)
                }
 
                if (p->p_lflag & P_LTRACED && (p->p_lflag & P_LPPWAIT) == 0) {
                }
 
                if (p->p_lflag & P_LTRACED && (p->p_lflag & P_LPPWAIT) == 0) {

-                       return(signum);
+                       return signum;

                }
 
                /*
                }
 
                /*


@@ -2556,23 +3134,7 @@ CURSIG(proc_t p)
                 */
 
                switch ((long)p->p_sigacts->ps_sigact[signum]) {
                 */
 
                switch ((long)p->p_sigacts->ps_sigact[signum]) {

-               

                case (long)SIG_DFL:
                case (long)SIG_DFL:

-                       /*
-                        * Don't take default actions on system processes.
-                        */
-                       if (p->p_ppid == 0) {
-#if DIAGNOSTIC
-                               /*
-                                * Are you sure you want to ignore SIGSEGV
-                                * in init? XXX
-                                */
-                               printf("Process (pid %d) got signal %d\n",
-                                       p->p_pid, signum);
-#endif
-                               break;                          /* == ignore */
-                       }
-                       

                        /*
                         * If there is a pending stop signal to process
                         * with default action, stop here,
                        /*
                         * If there is a pending stop signal to process
                         * with default action, stop here,


@@ -2586,10 +3148,10 @@ CURSIG(proc_t p)
                                pg = proc_pgrp(p);
 
                                if (p->p_lflag & P_LTRACED ||
                                pg = proc_pgrp(p);
 
                                if (p->p_lflag & P_LTRACED ||

-                                       (pg->pg_jobc == 0 &&
-                                       prop & SA_TTYSTOP)) {
+                                   (pg->pg_jobc == 0 &&
+                                   prop & SA_TTYSTOP)) {

                                        pg_rele(pg);
                                        pg_rele(pg);

-                                       break;  /* == ignore */
+                                       break;  /* == ignore */

                                }
                                pg_rele(pg);
                                retnum = signum;
                                }
                                pg_rele(pg);
                                retnum = signum;


@@ -2599,11 +3161,11 @@ CURSIG(proc_t p)
                                 * Except for SIGCONT, shouldn't get here.
                                 * Default action is to ignore; drop it.
                                 */
                                 * Except for SIGCONT, shouldn't get here.
                                 * Default action is to ignore; drop it.
                                 */

-                               break;          /* == ignore */
+                               break;          /* == ignore */

                        } else {
                        } else {

-                               return (signum);
+                               return signum;

                        }
                        }

-                       /*NOTREACHED*/
+               /*NOTREACHED*/

 
                case (long)SIG_IGN:
                        /*
 
                case (long)SIG_IGN:
                        /*


@@ -2612,16 +3174,17 @@ CURSIG(proc_t p)
                         * than SIGCONT, unless process is traced.
                         */
                        if ((prop & SA_CONT) == 0 &&
                         * than SIGCONT, unless process is traced.
                         */
                        if ((prop & SA_CONT) == 0 &&

-                               (p->p_lflag & P_LTRACED) == 0)
+                           (p->p_lflag & P_LTRACED) == 0) {

                                printf("issignal\n");
                                printf("issignal\n");

-                       break;          /* == ignore */
+                       }
+                       break;          /* == ignore */

 
                default:
                        /*
                         * This signal has an action, let
                         * postsig() process it.
                         */
 
                default:
                        /*
                         * This signal has an action, let
                         * postsig() process it.
                         */

-                       return (signum);
+                       return signum;

                }
        }
        /* NOTREACHED */
                }
        }
        /* NOTREACHED */


@@ -2657,15 +3220,18 @@ postsig_locked(int signum)
        uint32_t code;
        int mask, returnmask;
        struct uthread * ut;
        uint32_t code;
        int mask, returnmask;
        struct uthread * ut;

+       os_reason_t ut_exit_reason = OS_REASON_NULL;

 
 #if DIAGNOSTIC
 
 #if DIAGNOSTIC

-       if (signum == 0)
+       if (signum == 0) {

                panic("postsig");
                panic("postsig");

+       }

        /*
         *      This must be called on master cpu
         */
        /*
         *      This must be called on master cpu
         */

-       if (cpu_number() != master_cpu)
+       if (cpu_number() != master_cpu) {

                panic("psig not on master");
                panic("psig not on master");

+       }

 #endif
 
        /*
 #endif
 
        /*


@@ -2686,19 +3252,30 @@ postsig_locked(int signum)
                 * Default catcher, where the default is to kill
                 * the process.  (Other cases were ignored above.)
                 */
                 * Default catcher, where the default is to kill
                 * the process.  (Other cases were ignored above.)
                 */

-               sig_lock_to_exit(p);
+
+               /*
+                * exit_with_reason() below will consume a reference to the thread's exit reason, so we take another
+                * reference so the thread still has one even after we call exit_with_reason(). The thread's reference will
+                * ultimately be destroyed in uthread_cleanup().
+                */
+               ut_exit_reason = ut->uu_exit_reason;
+               os_reason_ref(ut_exit_reason);
+

                p->p_acflag |= AXSIG;
                if (sigprop[signum] & SA_CORE) {
                        p->p_sigacts->ps_sig = signum;
                        proc_signalend(p, 1);
                        proc_unlock(p);
                p->p_acflag |= AXSIG;
                if (sigprop[signum] & SA_CORE) {
                        p->p_sigacts->ps_sig = signum;
                        proc_signalend(p, 1);
                        proc_unlock(p);

-                       if (coredump(p, 0, 0) == 0)
+#if CONFIG_COREDUMP
+                       if (coredump(p, 0, 0) == 0) {

                                signum |= WCOREFLAG;
                                signum |= WCOREFLAG;

-               } else  {
+                       }
+#endif
+               } else {

                        proc_signalend(p, 1);
                        proc_unlock(p);
                }
                        proc_signalend(p, 1);
                        proc_unlock(p);
                }

-               
+

 #if CONFIG_DTRACE
                bzero((caddr_t)&(ut->t_dtrace_siginfo), sizeof(ut->t_dtrace_siginfo));
 
 #if CONFIG_DTRACE
                bzero((caddr_t)&(ut->t_dtrace_siginfo), sizeof(ut->t_dtrace_siginfo));
 


@@ -2715,15 +3292,17 @@ postsig_locked(int signum)
                default:
                        break;
                }
                default:
                        break;
                }

-               
+

 
                DTRACE_PROC3(signal__handle, int, signum, siginfo_t *, &(ut->t_dtrace_siginfo),
 
                DTRACE_PROC3(signal__handle, int, signum, siginfo_t *, &(ut->t_dtrace_siginfo),

-                                       void (*)(void), SIG_DFL);
+                   void (*)(void), SIG_DFL);

 #endif
 
                KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_FRCEXIT) | DBG_FUNC_NONE,
 #endif
 
                KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_FRCEXIT) | DBG_FUNC_NONE,

-                                             p->p_pid, W_EXITCODE(0, signum), 3, 0, 0);
-               exit1(p, W_EXITCODE(0, signum), (int *)NULL);
+                   p->p_pid, W_EXITCODE(0, signum), 3, 0, 0);
+
+               exit_with_reason(p, W_EXITCODE(0, signum), (int *)NULL, TRUE, TRUE, 0, ut_exit_reason);
+

                proc_lock(p);
                return;
        } else {
                proc_lock(p);
                return;
        } else {


@@ -2731,9 +3310,10 @@ postsig_locked(int signum)
                 * If we get here, the signal must be caught.
                 */
 #if DIAGNOSTIC
                 * If we get here, the signal must be caught.
                 */
 #if DIAGNOSTIC

-               if (catcher == SIG_IGN || (ut->uu_sigmask & mask))
+               if (catcher == SIG_IGN || (ut->uu_sigmask & mask)) {

                        log(LOG_WARNING,
                        log(LOG_WARNING,

-                               "postsig: processing masked or ignored signal\n");
+                           "postsig: processing masked or ignored signal\n");
+               }

 #endif
 
                /*
 #endif
 
                /*


@@ -2749,14 +3329,18 @@ postsig_locked(int signum)
                        returnmask = ut->uu_oldmask;
                        ut->uu_flag &= ~UT_SAS_OLDMASK;
                        ut->uu_oldmask = 0;
                        returnmask = ut->uu_oldmask;
                        ut->uu_flag &= ~UT_SAS_OLDMASK;
                        ut->uu_oldmask = 0;

-               } else
+               } else {

                        returnmask = ut->uu_sigmask;
                        returnmask = ut->uu_sigmask;

+               }

                ut->uu_sigmask |= ps->ps_catchmask[signum];
                ut->uu_sigmask |= ps->ps_catchmask[signum];

-               if ((ps->ps_signodefer & mask) == 0)
+               if ((ps->ps_signodefer & mask) == 0) {

                        ut->uu_sigmask |= mask;
                        ut->uu_sigmask |= mask;

+               }
+               sigset_t siginfo = ps->ps_siginfo;

                if ((signum != SIGILL) && (signum != SIGTRAP) && (ps->ps_sigreset & mask)) {
                if ((signum != SIGILL) && (signum != SIGTRAP) && (ps->ps_sigreset & mask)) {

-                       if ((signum != SIGCONT) && (sigprop[signum] & SA_IGNORE))
+                       if ((signum != SIGCONT) && (sigprop[signum] & SA_IGNORE)) {

                                p->p_sigignore |= mask;
                                p->p_sigignore |= mask;

+                       }

                        ps->ps_sigact[signum] = SIG_DFL;
                        ps->ps_siginfo &= ~mask;
                        ps->ps_signodefer &= ~mask;
                        ps->ps_sigact[signum] = SIG_DFL;
                        ps->ps_siginfo &= ~mask;
                        ps->ps_signodefer &= ~mask;


@@ -2769,7 +3353,7 @@ postsig_locked(int signum)
                        ps->ps_code = 0;
                }
                OSIncrementAtomicLong(&p->p_stats->p_ru.ru_nsignals);
                        ps->ps_code = 0;
                }
                OSIncrementAtomicLong(&p->p_stats->p_ru.ru_nsignals);

-               sendsig(p, catcher, signum, returnmask, code);
+               sendsig(p, catcher, signum, returnmask, code, siginfo);

        }
        proc_signalend(p, 1);
 }
        }
        proc_signalend(p, 1);
 }


@@ -2783,34 +3367,36 @@ postsig_locked(int signum)
  */
 
 static int
  */
 
 static int

-filt_sigattach(struct knote *kn)
+filt_sigattach(struct knote *kn, __unused struct kevent_qos_s *kev)

 {
        proc_t p = current_proc();  /* can attach only to oneself */
 
        proc_klist_lock();
 
 {
        proc_t p = current_proc();  /* can attach only to oneself */
 
        proc_klist_lock();
 

-       kn->kn_ptr.p_proc = p;
-       kn->kn_flags |= EV_CLEAR;               /* automatically set */
+       kn->kn_proc = p;
+       kn->kn_flags |= EV_CLEAR; /* automatically set */
+       kn->kn_sdata = 0;         /* incoming data is ignored */

 
        KNOTE_ATTACH(&p->p_klist, kn);
 
        proc_klist_unlock();
 
 
        KNOTE_ATTACH(&p->p_klist, kn);
 
        proc_klist_unlock();
 

-       return (0);
+       /* edge-triggered events can't have fired before we attached */
+       return 0;

 }
 
 /*
  * remove the knote from the process list, if it hasn't already
 }
 
 /*
  * remove the knote from the process list, if it hasn't already

- * been removed by exit processing.  
+ * been removed by exit processing.

  */
  */

-          
+

 static void
 filt_sigdetach(struct knote *kn)
 {
 static void
 filt_sigdetach(struct knote *kn)
 {

-       proc_t p = kn->kn_ptr.p_proc;
+       proc_t p = kn->kn_proc;

 
        proc_klist_lock();
 
        proc_klist_lock();

-       kn->kn_ptr.p_proc = NULL;
+       kn->kn_proc = NULL;

        KNOTE_DETACH(&p->p_klist, kn);
        proc_klist_unlock();
 }
        KNOTE_DETACH(&p->p_klist, kn);
        proc_klist_unlock();
 }


@@ -2827,40 +3413,55 @@ filt_sigdetach(struct knote *kn)
 static int
 filt_signal(struct knote *kn, long hint)
 {
 static int
 filt_signal(struct knote *kn, long hint)
 {

-

        if (hint & NOTE_SIGNAL) {
                hint &= ~NOTE_SIGNAL;
 
        if (hint & NOTE_SIGNAL) {
                hint &= ~NOTE_SIGNAL;
 

-               if (kn->kn_id == (unsigned int)hint)
-                       kn->kn_data++;
+               if (kn->kn_id == (unsigned int)hint) {
+                       kn->kn_hook32++;
+               }

        } else if (hint & NOTE_EXIT) {
                panic("filt_signal: detected NOTE_EXIT event");
        }
 
        } else if (hint & NOTE_EXIT) {
                panic("filt_signal: detected NOTE_EXIT event");
        }
 

-       return (kn->kn_data != 0);
+       return kn->kn_hook32 != 0;

 }
 
 }
 

-static void
-filt_signaltouch(struct knote *kn, struct kevent64_s *kev, long type)
+static int
+filt_signaltouch(struct knote *kn, struct kevent_qos_s *kev)

 {
 {

+#pragma unused(kev)
+
+       int res;
+

        proc_klist_lock();
        proc_klist_lock();

-       switch (type) {
-       case EVENT_REGISTER:
-               kn->kn_sfflags = kev->fflags;
-               kn->kn_sdata = kev->data;
-               break;
-       case EVENT_PROCESS:
-               *kev = kn->kn_kevent;
-               if (kn->kn_flags & EV_CLEAR) {
-                       kn->kn_data = 0;
-                       kn->kn_fflags = 0;
-               }
-               break;
-       default:
-               panic("filt_machporttouch() - invalid type (%ld)", type);
-               break;
+
+       /*
+        * No data to save - just capture if it is already fired
+        */
+       res = (kn->kn_hook32 > 0);
+
+       proc_klist_unlock();
+
+       return res;
+}
+
+static int
+filt_signalprocess(struct knote *kn, struct kevent_qos_s *kev)
+{
+       int res = 0;
+
+       /*
+        * Snapshot the event data.
+        */
+
+       proc_klist_lock();
+       if (kn->kn_hook32) {
+               knote_fill_kevent(kn, kev, kn->kn_hook32);
+               kn->kn_hook32 = 0;
+               res = 1;

        }
        proc_klist_unlock();
        }
        proc_klist_unlock();

+       return res;

 }
 
 void
 }
 
 void


@@ -2868,51 +3469,52 @@ bsd_ast(thread_t thread)
 {
        proc_t p = current_proc();
        struct uthread *ut = get_bsdthread_info(thread);
 {
        proc_t p = current_proc();
        struct uthread *ut = get_bsdthread_info(thread);

-       int     signum;
-       user_addr_t pc;
+       int     signum;

        static int bsd_init_done = 0;
 
        static int bsd_init_done = 0;
 

-       if (p == NULL)
+       if (p == NULL) {

                return;
                return;

+       }

 
 

-       if ((p->p_flag & P_OWEUPC) && (p->p_flag & P_PROFIL)) {
-               pc = get_useraddr();
-               addupc_task(p, pc, 1);
-               OSBitAndAtomic(~((uint32_t)P_OWEUPC), &p->p_flag);
+       /* don't run bsd ast on exec copy or exec'ed tasks */
+       if (task_did_exec(current_task()) || task_is_exec_copy(current_task())) {
+               return;

        }
 
        if (timerisset(&p->p_vtimer_user.it_value)) {
        }
 
        if (timerisset(&p->p_vtimer_user.it_value)) {

-               uint32_t        microsecs;
+               uint32_t        microsecs;

 
                task_vtimer_update(p->task, TASK_VTIMER_USER, &microsecs);
 
                if (!itimerdecr(p, &p->p_vtimer_user, microsecs)) {
 
                task_vtimer_update(p->task, TASK_VTIMER_USER, &microsecs);
 
                if (!itimerdecr(p, &p->p_vtimer_user, microsecs)) {

-                       if (timerisset(&p->p_vtimer_user.it_value))
+                       if (timerisset(&p->p_vtimer_user.it_value)) {

                                task_vtimer_set(p->task, TASK_VTIMER_USER);
                                task_vtimer_set(p->task, TASK_VTIMER_USER);

-                       else
+                       } else {

                                task_vtimer_clear(p->task, TASK_VTIMER_USER);
                                task_vtimer_clear(p->task, TASK_VTIMER_USER);

+                       }

 
 

-                       psignal(p, SIGVTALRM);
+                       psignal_try_thread(p, thread, SIGVTALRM);

                }
        }
 
        if (timerisset(&p->p_vtimer_prof.it_value)) {
                }
        }
 
        if (timerisset(&p->p_vtimer_prof.it_value)) {

-               uint32_t        microsecs;
+               uint32_t        microsecs;

 
                task_vtimer_update(p->task, TASK_VTIMER_PROF, &microsecs);
 
                if (!itimerdecr(p, &p->p_vtimer_prof, microsecs)) {
 
                task_vtimer_update(p->task, TASK_VTIMER_PROF, &microsecs);
 
                if (!itimerdecr(p, &p->p_vtimer_prof, microsecs)) {

-                       if (timerisset(&p->p_vtimer_prof.it_value))
+                       if (timerisset(&p->p_vtimer_prof.it_value)) {

                                task_vtimer_set(p->task, TASK_VTIMER_PROF);
                                task_vtimer_set(p->task, TASK_VTIMER_PROF);

-                       else
+                       } else {

                                task_vtimer_clear(p->task, TASK_VTIMER_PROF);
                                task_vtimer_clear(p->task, TASK_VTIMER_PROF);

+                       }

 
 

-                       psignal(p, SIGPROF);
+                       psignal_try_thread(p, thread, SIGPROF);

                }
        }
 
        if (timerisset(&p->p_rlim_cpu)) {
                }
        }
 
        if (timerisset(&p->p_rlim_cpu)) {

-               struct timeval          tv;
+               struct timeval          tv;

 
                task_vtimer_update(p->task, TASK_VTIMER_RLIM, (uint32_t *) &tv.tv_usec);
 
 
                task_vtimer_update(p->task, TASK_VTIMER_RLIM, (uint32_t *) &tv.tv_usec);
 


@@ -2922,21 +3524,20 @@ bsd_ast(thread_t thread)
                        timersub(&p->p_rlim_cpu, &tv, &p->p_rlim_cpu);
                        proc_spinunlock(p);
                } else {
                        timersub(&p->p_rlim_cpu, &tv, &p->p_rlim_cpu);
                        proc_spinunlock(p);
                } else {

-

                        timerclear(&p->p_rlim_cpu);
                        proc_spinunlock(p);
 
                        task_vtimer_clear(p->task, TASK_VTIMER_RLIM);
 
                        timerclear(&p->p_rlim_cpu);
                        proc_spinunlock(p);
 
                        task_vtimer_clear(p->task, TASK_VTIMER_RLIM);
 

-                       psignal(p, SIGXCPU);
+                       psignal_try_thread(p, thread, SIGXCPU);

                }
        }
 
 #if CONFIG_DTRACE
        if (ut->t_dtrace_sig) {
                }
        }
 
 #if CONFIG_DTRACE
        if (ut->t_dtrace_sig) {

-           uint8_t dt_action_sig = ut->t_dtrace_sig;
-           ut->t_dtrace_sig = 0;
-           psignal(p, dt_action_sig);
+               uint8_t dt_action_sig = ut->t_dtrace_sig;
+               ut->t_dtrace_sig = 0;
+               psignal(p, dt_action_sig);

        }
 
        if (ut->t_dtrace_stop) {
        }
 
        if (ut->t_dtrace_stop) {


@@ -2948,7 +3549,7 @@ bsd_ast(thread_t thread)
        }
 
        if (ut->t_dtrace_resumepid) {
        }
 
        if (ut->t_dtrace_resumepid) {

-               proc_t resumeproc = proc_find(ut->t_dtrace_resumepid);
+               proc_t resumeproc = proc_find((int)ut->t_dtrace_resumepid);

                ut->t_dtrace_resumepid = 0;
                if (resumeproc != PROC_NULL) {
                        proc_lock(resumeproc);
                ut->t_dtrace_resumepid = 0;
                if (resumeproc != PROC_NULL) {
                        proc_lock(resumeproc);


@@ -2957,28 +3558,33 @@ bsd_ast(thread_t thread)
                                resumeproc->p_dtrace_stop = 0;
                                proc_unlock(resumeproc);
                                task_resume_internal(resumeproc->task);
                                resumeproc->p_dtrace_stop = 0;
                                proc_unlock(resumeproc);
                                task_resume_internal(resumeproc->task);

-                       }
-                       else {
+                       } else {

                                proc_unlock(resumeproc);
                        }
                        proc_rele(resumeproc);
                }
        }
                                proc_unlock(resumeproc);
                        }
                        proc_rele(resumeproc);
                }
        }

-                   
+

 #endif /* CONFIG_DTRACE */
 
        proc_lock(p);
        if (CHECK_SIGNALS(p, current_thread(), ut)) {
 #endif /* CONFIG_DTRACE */
 
        proc_lock(p);
        if (CHECK_SIGNALS(p, current_thread(), ut)) {

-               while ( (signum = issignal_locked(p)) )
+               while ((signum = issignal_locked(p))) {

                        postsig_locked(signum);
                        postsig_locked(signum);

+               }

        }
        proc_unlock(p);
 
        }
        proc_unlock(p);
 

+#ifdef CONFIG_32BIT_TELEMETRY
+       if (task_consume_32bit_log_flag(p->task)) {
+               proc_log_32bit_telemetry(p);
+       }
+#endif /* CONFIG_32BIT_TELEMETRY */
+

        if (!bsd_init_done) {
                bsd_init_done = 1;
                bsdinit_task();
        }
        if (!bsd_init_done) {
                bsd_init_done = 1;
                bsdinit_task();
        }

-

 }
 
 /* ptrace set runnable */
 }
 
 /* ptrace set runnable */


@@ -2995,7 +3601,7 @@ pt_setrunnable(proc_t p)
                proc_unlock(p);
                if (p->sigwait) {
                        wakeup((caddr_t)&(p->sigwait));
                proc_unlock(p);
                if (p->sigwait) {
                        wakeup((caddr_t)&(p->sigwait));

-                       if ((p->p_lflag & P_LSIGEXC) == 0) {    // 5878479
+                       if ((p->p_lflag & P_LSIGEXC) == 0) {    // 5878479

                                task_release(task);
                        }
                }
                                task_release(task);
                        }
                }


@@ -3004,15 +3610,15 @@ pt_setrunnable(proc_t p)
 
 kern_return_t
 do_bsdexception(
 
 kern_return_t
 do_bsdexception(

-           int exc,
-           int code,
-           int sub)
+       int exc,
+       int code,
+       int sub)

 {
        mach_exception_data_type_t   codes[EXCEPTION_CODE_MAX];
 
 {
        mach_exception_data_type_t   codes[EXCEPTION_CODE_MAX];
 

-       codes[0] = code;        
+       codes[0] = code;

        codes[1] = sub;
        codes[1] = sub;

-       return(bsd_exception(exc, codes, 2));
+       return bsd_exception(exc, codes, 2);

 }
 
 int
 }
 
 int


@@ -3024,18 +3630,18 @@ proc_pendingsignals(proc_t p, sigset_t mask)
 
        proc_lock(p);
        /* If the process is in proc exit return no signal info */
 
        proc_lock(p);
        /* If the process is in proc exit return no signal info */

-       if (p->p_lflag & P_LPEXIT)  {
+       if (p->p_lflag & P_LPEXIT) {

                goto out;
        }
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
                goto out;
        }
 
        if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {

-               th = p->p_vforkact;     
+               th = p->p_vforkact;

                uth = (struct uthread *)get_bsdthread_info(th);
                if (uth) {
                        bits = (((uth->uu_siglist & ~uth->uu_sigmask) & ~p->p_sigignore) & mask);
                }
                goto out;
                uth = (struct uthread *)get_bsdthread_info(th);
                if (uth) {
                        bits = (((uth->uu_siglist & ~uth->uu_sigmask) & ~p->p_sigignore) & mask);
                }
                goto out;

-       } 
+       }

 
        bits = 0;
        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {
 
        bits = 0;
        TAILQ_FOREACH(uth, &p->p_uthlist, uu_list) {


@@ -3043,14 +3649,14 @@ proc_pendingsignals(proc_t p, sigset_t mask)
        }
 out:
        proc_unlock(p);
        }
 out:
        proc_unlock(p);

-       return(bits);
+       return bits;

 }
 
 int
 thread_issignal(proc_t p, thread_t th, sigset_t mask)
 {
        struct uthread * uth;
 }
 
 int
 thread_issignal(proc_t p, thread_t th, sigset_t mask)
 {
        struct uthread * uth;

-       sigset_t  bits=0;
+       sigset_t  bits = 0;

 
        proc_lock(p);
        uth = (struct uthread *)get_bsdthread_info(th);
 
        proc_lock(p);
        uth = (struct uthread *)get_bsdthread_info(th);


@@ -3058,7 +3664,7 @@ thread_issignal(proc_t p, thread_t th, sigset_t mask)
                bits = (((uth->uu_siglist & ~uth->uu_sigmask) & ~p->p_sigignore) & mask);
        }
        proc_unlock(p);
                bits = (((uth->uu_siglist & ~uth->uu_sigmask) & ~p->p_sigignore) & mask);
        }
        proc_unlock(p);

-       return(bits);
+       return bits;

 }
 
 /*
 }
 
 /*


@@ -3067,58 +3673,70 @@ thread_issignal(proc_t p, thread_t th, sigset_t mask)
 int
 hassigprop(int sig, int prop)
 {
 int
 hassigprop(int sig, int prop)
 {

-       return (sigprop[sig] & prop);
+       return sigprop[sig] & prop;

 }
 
 void
 pgsigio(pid_t pgid, int sig)
 }
 
 void
 pgsigio(pid_t pgid, int sig)

-{ 
+{

        proc_t p = PROC_NULL;
 
        proc_t p = PROC_NULL;
 

-       if (pgid < 0) 
+       if (pgid < 0) {

                gsignal(-(pgid), sig);
                gsignal(-(pgid), sig);

-
-       else if (pgid > 0 && (p = proc_find(pgid)) != 0) 
+       } else if (pgid > 0 && (p = proc_find(pgid)) != 0) {

                psignal(p, sig);
                psignal(p, sig);

-       if (p != PROC_NULL)
+       }
+       if (p != PROC_NULL) {

                proc_rele(p);
                proc_rele(p);

+       }

 }
 
 void
 proc_signalstart(proc_t p, int locked)
 {
 }
 
 void
 proc_signalstart(proc_t p, int locked)
 {

-       if (!locked)
+       if (!locked) {

                proc_lock(p);
                proc_lock(p);

+       }
+
+       if (p->p_signalholder == current_thread()) {
+               panic("proc_signalstart: thread attempting to signal a process for which it holds the signal lock");
+       }
+

        p->p_sigwaitcnt++;
        p->p_sigwaitcnt++;

-       while ((p->p_lflag & P_LINSIGNAL) == P_LINSIGNAL)
+       while ((p->p_lflag & P_LINSIGNAL) == P_LINSIGNAL) {

                msleep(&p->p_sigmask, &p->p_mlock, 0, "proc_signstart", NULL);
                msleep(&p->p_sigmask, &p->p_mlock, 0, "proc_signstart", NULL);

+       }

        p->p_sigwaitcnt--;
 
        p->p_lflag |= P_LINSIGNAL;
        p->p_signalholder = current_thread();
        p->p_sigwaitcnt--;
 
        p->p_lflag |= P_LINSIGNAL;
        p->p_signalholder = current_thread();

-       if (!locked)
+       if (!locked) {

                proc_unlock(p);
                proc_unlock(p);

+       }

 }
 
 void
 proc_signalend(proc_t p, int locked)
 {
 }
 
 void
 proc_signalend(proc_t p, int locked)
 {

-       if (!locked)
+       if (!locked) {

                proc_lock(p);
                proc_lock(p);

+       }

        p->p_lflag &= ~P_LINSIGNAL;
 
        p->p_lflag &= ~P_LINSIGNAL;
 

-       if (p->p_sigwaitcnt > 0)
+       if (p->p_sigwaitcnt > 0) {

                wakeup(&p->p_sigmask);
                wakeup(&p->p_sigmask);

+       }

 
        p->p_signalholder = NULL;
 
        p->p_signalholder = NULL;

-       if (!locked)
+       if (!locked) {

                proc_unlock(p);
                proc_unlock(p);

+       }

 }
 
 void
 sig_lock_to_exit(proc_t p)
 {
 }
 
 void
 sig_lock_to_exit(proc_t p)
 {

-       thread_t        self = current_thread();
+       thread_t        self = current_thread();

 
        p->exit_thread = self;
        proc_unlock(p);
 
        p->exit_thread = self;
        proc_unlock(p);


@@ -3132,11 +3750,11 @@ sig_lock_to_exit(proc_t p)
 int
 sig_try_locked(proc_t p)
 {
 int
 sig_try_locked(proc_t p)
 {

-       thread_t        self = current_thread();
+       thread_t        self = current_thread();

 
        while (p->sigwait || p->exit_thread) {
                if (p->exit_thread) {
 
        while (p->sigwait || p->exit_thread) {
                if (p->exit_thread) {

-                       return(0);
+                       return 0;

                }
                msleep((caddr_t)&p->sigwait_thread, &p->p_mlock, PCATCH | PDROP, 0, 0);
                if (thread_should_abort(self)) {
                }
                msleep((caddr_t)&p->sigwait_thread, &p->p_mlock, PCATCH | PDROP, 0, 0);
                if (thread_should_abort(self)) {