/*
- * Copyright (c) 1995-2007 Apple Inc. All rights reserved.
+ * Copyright (c) 1995-2016 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
#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 <sys/vm.h>
#include <sys/user.h> /* for coredump */
#include <kern/ast.h> /* for APC support */
-#include <kern/lock.h>
+#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/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 <sys/codesign.h>
/*
* Missing prototypes that Mach should export
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 boolean_t thread_should_abort(thread_t);
extern unsigned int get_useraddr(void);
+extern boolean_t task_did_exec(task_t task);
+extern boolean_t task_is_exec_copy(task_t task);
/*
* ---
static void stop(proc_t, proc_t);
int cansignal(proc_t, kauth_cred_t, proc_t, 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);
+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));
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);
+static int filt_signaltouch(struct knote *kn, struct kevent_internal_s *kev);
+static int filt_signalprocess(struct knote *kn, struct filt_process_s *data, struct kevent_internal_s *kev);
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 */
#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)
if (p == q)
return(1);
+ /* you can't send launchd SIGKILL, even if root */
+ if (signum == SIGKILL && q == initproc)
+ return(0);
+
if (!suser(uc, NULL))
return (1); /* root can always signal */
return (0);
}
+/*
+ * <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;
+
+#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
signum = uap->signum;
if (signum <= 0 || signum >= NSIG ||
- signum == SIGKILL || signum == SIGSTOP)
+ 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);
+ __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];
if (IS_64BIT_PROCESS(p)) {
struct user64_sigaction vec64;
-
sigaction_kern_to_user64(sa, &vec64);
error = copyout(&vec64, uap->osa, sizeof(vec64));
} else {
struct user32_sigaction vec32;
-
sigaction_kern_to_user32(sa, &vec32);
error = copyout(&vec32, uap->osa, sizeof(vec32));
}
if (error)
return (error);
}
+
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);
- __vec.sa_flags &= SA_USERSPACE_MASK; /* Only pass on valid sa_flags */
error = setsigvec(p, current_thread(), signum, &__vec, FALSE);
}
+
return (error);
}
struct sigacts *ps = p->p_sigacts;
int bit;
+ assert(signum < NSIG);
+
if ((signum == SIGKILL || signum == SIGSTOP) &&
sa->sa_handler != SIG_DFL)
return(EINVAL);
{
int i;
- for (i = 0; i < NSIG; i++)
+ for (i = 1; i < NSIG; i++)
if (sigprop[i] & SA_IGNORE && i != SIGCONT)
p->p_sigignore |= sigmask(i);
}
return(EINVAL);
}
+__attribute__((noreturn))
void
__posix_sem_syscall_return(kern_return_t kern_result)
{
/* NOTREACHED */
}
+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)
+{
+ 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;
+
+ 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 = (char *) kalloc(EXIT_REASON_USER_DESC_MAX_LEN);
+
+ 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;
+ kfree(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,
+ reason_user_desc_len,
+ &data_addr)) {
+
+ kcdata_memcpy(&exit_reason->osr_kcd_descriptor, (mach_vm_address_t) data_addr,
+ reason_user_desc, 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) {
+ kfree(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) {
+ kfree(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
+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, 0)) {
+ proc_rele(target_proc);
+ return EPERM;
+ }
+
+ 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);
+
+ 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)
+{
+ 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_filt(proc_t p, void * arg)
{
/* PGRP_DROPREF drops the pgrp refernce */
- pgrp_iterate(pgrp, PGRP_BLOCKITERATE | PGRP_DROPREF, killpg1_callback, &karg,
+ pgrp_iterate(pgrp, PGRP_DROPREF, killpg1_callback, &karg,
killpg1_pgrpfilt, NULL);
}
error = (nfound ? 0 : (posix ? EPERM : ESRCH));
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);
}
}
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);
}
}
* 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;
p = (proc_t)(get_bsdtask_info(sig_task));
uth = get_bsdthread_info(sig_actthread);
- if (uth && (uth->uu_flag & UT_VFORK))
+ if (uth->uu_flag & UT_VFORK)
p = uth->uu_proc;
proc_lock(p);
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);
}
+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);
+ }
+
+ 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)
{
thread_t sig_thread;
struct task * sig_task = p->task;
kern_return_t kret;
-
+
*thr = THREAD_NULL;
if ((p->p_lflag & P_LINVFORK) && p->p_vforkact) {
return(KERN_SUCCESS);
}else
return(KERN_FAILURE);
- }
+ }
- proc_lock(p);
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);
}
}
}
- proc_unlock(p);
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,
+ 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,
+ strlen(default_sender_procname) + 1);
+ }
+ } else {
+ printf("build_signal_reason: exceeded space in signal reason buf, unable to log procname\n");
+ }
+
+ return signal_reason;
+}
+
/*
* Send the signal to the process. If the signal has an action, the action
* 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.
* 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;
- 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 signal number");
+ panic("psignal: bad signal number %d", signum);
+
mask = sigmask(signum);
prop = sigprop[signum];
}
#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
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;
- sig_thread = (struct thread *)0;
+ sig_thread = THREAD_NULL;
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;
+ }
/*
* do not send signals to the process that has the thread
* 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;
+ }
if( (flavor & (PSIG_VFORK | PSIG_THREAD)) == 0) {
proc_knote(sig_proc, NOTE_SIGNAL | signum);
if ((flavor & PSIG_LOCKED)== 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);
- 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;
+ } 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);
/* If successful return with ast set */
kret = get_signalthread(sig_proc, signum, &sig_thread);
}
+
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);
/*
* action will be SIG_DFL here.)
*/
if (sig_proc->p_sigignore & mask)
- goto psigout;
+ goto sigout_locked;
+
if (uth->uu_sigwait & mask)
action = KERN_SIG_WAIT;
else if (uth->uu_sigmask & mask)
}
}
-
- 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) &&
(sig_proc->p_lflag & P_LTRACED) == 0)
sig_proc->p_nice = NZERO;
* 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 &&
action == SIG_DFL) {
pg_rele(pg);
- goto psigout;
+ goto sigout_locked;
}
pg_rele(pg);
- proc_lock(sig_proc);
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)) {
- proc_unlock(sig_proc);
- goto psigout;
- }
+ if ((action == KERN_SIG_HOLD) && ((prop & SA_CONT) == 0 || sig_proc->p_stat != SSTOP))
+ 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.
+ *
+ * TODO: p_nice isn't hooked up to the scheduler...
*/
if ((signum == SIGKILL) && (sig_proc->p_nice > NZERO)) {
sig_proc->p_nice = NZERO;
if (sig_proc->p_lflag & P_LTRACED) {
if (sig_proc->p_stat != SSTOP)
goto runlocked;
- else {
- proc_unlock(sig_proc);
- goto psigout;
- }
+ else
+ goto sigout_locked;
}
+
if ((flavor & PSIG_VFORK) != 0)
goto runlocked;
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(sig_task);
- goto psigout;
+ (void) task_resume_internal(sig_task);
}
- proc_unlock(sig_proc);
- goto psigout;
+ goto sigout_locked;
}
if (action != SIG_DFL) {
*/
if (prop & SA_CONT) {
OSBitOrAtomic(P_CONTINUED, &sig_proc->p_flag);
- proc_unlock(sig_proc);
- (void) task_resume(sig_task);
- proc_lock(sig_proc);
+ (void) task_resume_internal(sig_task);
sig_proc->p_stat = SRUN;
} else if (sig_proc->p_stat == SSTOP) {
- proc_unlock(sig_proc);
- goto psigout;
+ goto sigout_locked;
}
/*
* Fill out siginfo structure information to pass to the
* Note: Avoid the SIGCHLD recursion case!
*/
if (signum != SIGCHLD) {
- proc_unlock(sig_proc);
r_uid = kauth_getruid();
- proc_lock(sig_proc);
sig_proc->si_pid = current_proc()->p_pid;
sig_proc->si_status = W_EXITCODE(signum, 0);
} else {
/* Default action - varies */
if (mask & stopsigmask) {
+ assert(signal_reason == NULL);
/*
* These are the signals which by default
* stop a process.
* 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);
- 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
psignal(pp, SIGCHLD);
}
- if (pp != PROC_NULL)
+ if (pp != PROC_NULL) {
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);
- /*
- * enters switch with sig_proc lock held but dropped when
- * gets out of switch
- */
switch (signum) {
/*
* Signals ignored by default have been dealt
* Process will be running after 'run'
*/
sig_proc->p_stat = SRUN;
- proc_unlock(sig_proc);
/*
* In scenarios where suspend/resume are racing
* the signal we are missing AST_BSD by the time
* We would need to cover this approp down the line.
*/
act_set_astbsd(sig_thread);
- thread_abort(sig_thread);
+ 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);
+ }
- goto psigout;
+ 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.
*/
+ assert(signal_reason == NULL);
OSBitOrAtomic(P_CONTINUED, &sig_proc->p_flag);
sig_proc->p_contproc = sig_proc->p_pid;
- proc_unlock(sig_proc);
- (void) task_resume(sig_task);
- proc_lock(sig_proc);
+ (void) task_resume_internal(sig_task);
+
/*
* When processing a SIGCONT, we need to check
* to see if there are signals pending that
uth->uu_siglist &= ~mask;
sig_proc->p_stat = SRUN;
- proc_unlock(sig_proc);
- goto psigout;
+ goto sigout_locked;
default:
/*
*/
if (((flavor & (PSIG_VFORK|PSIG_THREAD)) == 0) && (action == SIG_DFL) && (prop & SA_KILL)) {
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;
}
/*
* resume it.
*/
if (sig_proc->p_stat == SSTOP) {
- proc_unlock(sig_proc);
- goto psigout;
+ goto sigout_locked;
}
goto runlocked;
}
*/
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);
+ uth->uu_siglist |= sigmask(sig_proc->p_xstat);
+
if ((flavor & PSIG_VFORK) != 0) {
sig_proc->p_stat = SRUN;
}
- proc_unlock(sig_proc);
} else {
/*
* setrunnable(p) in BSD and
* Wake up the thread if it is interruptible.
*/
sig_proc->p_stat = SRUN;
- proc_unlock(sig_proc);
if ((flavor & PSIG_VFORK) == 0)
thread_abort_safely(sig_thread);
}
-psigout:
+
+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);
+ }
+
+ proc_unlock(sig_proc);
+
+sigout_unlocked:
+ os_reason_free(signal_reason);
if ((flavor & PSIG_LOCKED)== 0) {
proc_signalend(sig_proc, 0);
}
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_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)
{
- 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_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
* postsig(signum);
*/
int
-issignal(proc_t p)
+issignal_locked(proc_t p)
{
int signum, mask, prop, sigbits;
thread_t cur_act;
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 */
- proc_lock(p);
/*
* Try to grab the signal lock.
*/
if (sig_try_locked(p) <= 0) {
- proc_unlock(p);
- return(0);
+ return 0;
}
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)
sigbits &= ~stopsigmask;
* 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;
}
+
if (p->p_lflag & P_LTRACED && (p->p_lflag & P_LPPWAIT) == 0) {
- task_t task;
/*
- * 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;
-
+
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);
/*
* XXX Have to really stop for debuggers;
* XXX stop() doesn't do the right thing.
- * XXX Inline the task_suspend because we
- * XXX have to diddle Unix state in the
- * XXX middle of it.
*/
task = p->task;
- task_suspend(task);
+ task_suspend_internal(task);
proc_lock(p);
p->sigwait = TRUE;
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);
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);
- 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 parent wants us to take the signal,
* then it will leave it in p->p_xstat;
signum = p->p_xstat;
if (signum == 0)
continue;
+
/*
* Put the new signal into p_siglist. If the
* signal is being masked, look for other signals.
*/
switch ((long)p->p_sigacts->ps_sigact[signum]) {
-
+
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,
prop & SA_TTYSTOP)) {
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;
-
p->p_stat = SSTOP;
p->p_lflag &= ~P_LWAITED;
proc_unlock(p);
* Except for SIGCONT, shouldn't get here.
* Default action is to ignore; drop it.
*/
- break; /* == ignore */
+ break; /* ignore signal */
} 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
if ((prop & SA_CONT) == 0 &&
(p->p_lflag & P_LTRACED) == 0)
printf("issignal\n");
- break; /* == ignore */
+ break; /* ignore signal */
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 */
+
+deliver_sig:
+ ut->uu_siglist &= ~mask;
+ retval = signum;
+
out:
proc_signalend(p, 1);
- proc_unlock(p);
- return(retval);
+ return retval;
}
/* called from _sleep */
switch ((long)p->p_sigacts->ps_sigact[signum]) {
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,
wakeup((caddr_t)parent);
proc_list_unlock();
}
- (void) task_suspend(p->task); /*XXX*/
+ (void) task_suspend_internal(p->task);
}
/*
* from the current set of pending signals.
*/
void
-postsig(int signum)
+postsig_locked(int signum)
{
proc_t p = current_proc();
struct sigacts *ps = p->p_sigacts;
panic("psig not on master");
#endif
- proc_lock(p);
/*
* Try to grab the signal lock.
*/
if (sig_try_locked(p) <= 0) {
- proc_unlock(p);
return;
}
p->p_sigacts->ps_sig = signum;
proc_signalend(p, 1);
proc_unlock(p);
- if (coredump(p) == 0)
+#if CONFIG_COREDUMP
+ if (coredump(p, 0, 0) == 0)
signum |= WCOREFLAG;
+#endif
} else {
proc_signalend(p, 1);
proc_unlock(p);
ut->t_dtrace_siginfo.si_uid = p->si_uid;
ut->t_dtrace_siginfo.si_status = WEXITSTATUS(p->si_status);
+ /* Fire DTrace proc:::fault probe when signal is generated by hardware. */
+ switch (signum) {
+ case SIGILL: case SIGBUS: case SIGSEGV: case SIGFPE: case SIGTRAP:
+ DTRACE_PROC2(fault, int, (int)(ut->uu_code), siginfo_t *, &(ut->t_dtrace_siginfo));
+ break;
+ default:
+ break;
+ }
+
+
DTRACE_PROC3(signal__handle, int, signum, siginfo_t *, &(ut->t_dtrace_siginfo),
void (*)(void), SIG_DFL);
#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);
+
+ /*
+ * exit_with_reason() will consume a reference to the thread's exit reason, so we take another
+ * reference for the thread. This reference will be destroyed in uthread_cleanup().
+ */
+ os_reason_ref(ut->uu_exit_reason);
+ exit_with_reason(p, W_EXITCODE(0, signum), (int *)NULL, TRUE, TRUE, 0, ut->uu_exit_reason);
+
+ proc_lock(p);
return;
} else {
/*
sendsig(p, catcher, signum, returnmask, code);
}
proc_signalend(p, 1);
- proc_unlock(p);
}
/*
proc_klist_lock();
kn->kn_ptr.p_proc = p;
- kn->kn_flags |= EV_CLEAR; /* automatically set */
KNOTE_ATTACH(&p->p_klist, kn);
proc_klist_unlock();
+ /* edge-triggered events can't have fired before we attached */
return (0);
}
return (kn->kn_data != 0);
}
-static void
-filt_signaltouch(struct knote *kn, struct kevent64_s *kev, long type)
+static int
+filt_signaltouch(
+ struct knote *kn,
+ struct kevent_internal_s *kev)
{
+#pragma unused(kev)
+
+ int res;
+
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;
+
+ if ((kn->kn_status & KN_UDATA_SPECIFIC) == 0)
+ kn->kn_udata = kev->udata;
+ /*
+ * No data to save -
+ * just capture if it is already fired
+ */
+ res = (kn->kn_data > 0);
+
+ proc_klist_unlock();
+
+ return res;
+}
+
+static int
+filt_signalprocess(
+ struct knote *kn,
+ __unused struct filt_process_s *data,
+ struct kevent_internal_s *kev)
+{
+ proc_klist_lock();
+
+ if (kn->kn_data == 0) {
+ proc_klist_unlock();
+ return 0;
}
+
+ /*
+ * Snapshot the event data.
+ * All signal events are EV_CLEAR, so
+ * add that and clear out the data field.
+ */
+ *kev = kn->kn_kevent;
+ kev->flags |= EV_CLEAR;
+ kn->kn_data = 0;
+
proc_klist_unlock();
+ return 1;
}
void
if (p == NULL)
return;
+ /* 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 ((p->p_flag & P_OWEUPC) && (p->p_flag & P_PROFIL)) {
pc = get_useraddr();
addupc_task(p, pc, 1);
else
task_vtimer_clear(p->task, TASK_VTIMER_USER);
- psignal(p, SIGVTALRM);
+ psignal_try_thread(p, thread, SIGVTALRM);
}
}
else
task_vtimer_clear(p->task, TASK_VTIMER_PROF);
- psignal(p, SIGPROF);
+ psignal_try_thread(p, thread, SIGPROF);
}
}
task_vtimer_clear(p->task, TASK_VTIMER_RLIM);
- psignal(p, SIGXCPU);
+ psignal_try_thread(p, thread, SIGXCPU);
}
}
proc_lock(p);
p->p_dtrace_stop = 1;
proc_unlock(p);
- (void)task_suspend(p->task);
+ (void)task_suspend_internal(p->task);
}
if (ut->t_dtrace_resumepid) {
if (resumeproc->p_dtrace_stop) {
resumeproc->p_dtrace_stop = 0;
proc_unlock(resumeproc);
- task_resume(resumeproc->task);
+ task_resume_internal(resumeproc->task);
}
else {
proc_unlock(resumeproc);
#endif /* CONFIG_DTRACE */
+ proc_lock(p);
if (CHECK_SIGNALS(p, current_thread(), ut)) {
- while ( (signum = issignal(p)) )
- postsig(signum);
+ while ( (signum = issignal_locked(p)) )
+ postsig_locked(signum);
}
+ proc_unlock(p);
if (!bsd_init_done) {
bsd_init_done = 1;
{
if (!locked)
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++;
while ((p->p_lflag & P_LINSIGNAL) == P_LINSIGNAL)
msleep(&p->p_sigmask, &p->p_mlock, 0, "proc_signstart", NULL);
p->exit_thread = self;
proc_unlock(p);
- (void) task_suspend(p->task);
+
+ task_hold(p->task);
+ task_wait(p->task, FALSE);
+
proc_lock(p);
}
projects / apple / xnu.git / blobdiff