#include <sys/sysent.h>
#include <sys/ucontext.h>
#include <sys/wait.h>
+
+#include <sys/ux_exception.h>
+
#include <mach/thread_act.h> /* for thread_abort_safely */
#include <mach/thread_status.h>
/* Forward: */
-extern boolean_t machine_exception(int, mach_exception_code_t,
- mach_exception_subcode_t, int *, mach_exception_subcode_t *);
extern kern_return_t thread_getstatus(thread_t act, int flavor,
thread_state_t tstate, mach_msg_type_number_t *count);
extern kern_return_t thread_setstatus(thread_t thread, int flavor,
int sig;
user32_addr_t sinfo; /* siginfo32_t* */
user32_addr_t uctx; /* struct ucontext32 */
+ user32_addr_t token;
};
/*
int stack_size = 0;
int infostyle = UC_TRAD;
xstate_t sig_xstate;
+ user_addr_t token_uctx;
+ kern_return_t kr;
thread = current_thread();
ut = get_bsdthread_info(thread);
if (proc_is64bit(p)) {
x86_thread_state64_t *tstate64;
struct user_ucontext64 uctx64;
+ user64_addr_t token;
flavor = x86_THREAD_STATE64;
state_count = x86_THREAD_STATE64_COUNT;
*/
ua_fp -= sizeof(user_addr_t);
+ /*
+ * Generate the validation token for sigreturn
+ */
+ token_uctx = ua_uctxp;
+ kr = machine_thread_siguctx_pointer_convert_to_user(thread, &token_uctx);
+ assert(kr == KERN_SUCCESS);
+ token = (user64_addr_t)token_uctx ^ (user64_addr_t)ps->ps_sigreturn_token;
+
/*
* Build the signal context to be used by sigreturn.
*/
tstate64->rdx = sig;
tstate64->rcx = ua_sip;
tstate64->r8 = ua_uctxp;
-
+ tstate64->r9 = token;
} else {
x86_thread_state32_t *tstate32;
struct user_ucontext32 uctx32;
struct sigframe32 frame32;
+ user32_addr_t token;
flavor = x86_THREAD_STATE32;
state_count = x86_THREAD_STATE32_COUNT;
*/
ua_fp -= sizeof(frame32.retaddr);
+ /*
+ * Generate the validation token for sigreturn
+ */
+ token_uctx = ua_uctxp;
+ kr = machine_thread_siguctx_pointer_convert_to_user(thread, &token_uctx);
+ assert(kr == KERN_SUCCESS);
+ token = CAST_DOWN_EXPLICIT(user32_addr_t, token_uctx) ^
+ CAST_DOWN_EXPLICIT(user32_addr_t, ps->ps_sigreturn_token);
+
/*
* Build the argument list for the signal handler.
* Handler should call sigreturn to get out of it
frame32.catcher = CAST_DOWN_EXPLICIT(user32_addr_t, ua_catcher);
frame32.sinfo = CAST_DOWN_EXPLICIT(user32_addr_t, ua_sip);
frame32.uctx = CAST_DOWN_EXPLICIT(user32_addr_t, ua_uctxp);
+ frame32.token = token;
if (copyout((caddr_t)&frame32, ua_fp, sizeof (frame32)))
goto bad;
thread_t thread = current_thread();
struct uthread * ut;
+ struct sigacts *ps = p->p_sigacts;
int error;
int onstack = 0;
void * fs;
int rval = EJUSTRETURN;
xstate_t sig_xstate;
+ uint32_t sigreturn_validation;
+ user_addr_t token_uctx;
+ kern_return_t kr;
ut = (struct uthread *)get_bsdthread_info(thread);
sig_xstate = current_xstate();
+ sigreturn_validation = atomic_load_explicit(
+ &ps->ps_sigreturn_validation, memory_order_relaxed);
+ token_uctx = uap->uctx;
+ kr = machine_thread_siguctx_pointer_convert_to_user(thread, &token_uctx);
+ assert(kr == KERN_SUCCESS);
+
if (proc_is64bit(p)) {
struct user_ucontext64 uctx64;
+ user64_addr_t token;
if ((error = copyin(uap->uctx, (void *)&uctx64, sizeof (uctx64))))
return(error);
fs_count = thread_state64[sig_xstate].state_count;
fs = (void *)&mctxp->mctx_avx64.fs;
+ token = (user64_addr_t)token_uctx ^ (user64_addr_t)ps->ps_sigreturn_token;
+ if ((user64_addr_t)uap->token != token) {
+#if DEVELOPMENT || DEBUG
+ printf("process %s[%d] sigreturn token mismatch: received 0x%llx expected 0x%llx\n",
+ p->p_comm, p->p_pid, (user64_addr_t)uap->token, token);
+#endif /* DEVELOPMENT || DEBUG */
+ if (sigreturn_validation != PS_SIGRETURN_VALIDATION_DISABLED) {
+ rval = EINVAL;
+ }
+ }
} else {
struct user_ucontext32 uctx32;
+ user32_addr_t token;
if ((error = copyin(uap->uctx, (void *)&uctx32, sizeof (uctx32))))
return(error);
fs_flavor = thread_state32[sig_xstate].flavor;
fs_count = thread_state32[sig_xstate].state_count;
fs = (void *)&mctxp->mctx_avx32.fs;
+
+ token = CAST_DOWN_EXPLICIT(user32_addr_t, uap->uctx) ^
+ CAST_DOWN_EXPLICIT(user32_addr_t, ps->ps_sigreturn_token);
+ if ((user32_addr_t)uap->token != token) {
+#if DEVELOPMENT || DEBUG
+ printf("process %s[%d] sigreturn token mismatch: received 0x%x expected 0x%x\n",
+ p->p_comm, p->p_pid, (user32_addr_t)uap->token, token);
+#endif /* DEVELOPMENT || DEBUG */
+ if (sigreturn_validation != PS_SIGRETURN_VALIDATION_DISABLED) {
+ rval = EINVAL;
+ }
+ }
}
if (onstack)
if (ut->uu_siglist & ~ut->uu_sigmask)
signal_setast(thread);
+
+ if (rval == EINVAL) {
+ goto error_ret;
+ }
+
/*
* thread_set_state() does all the needed checks for the passed in
* content
*/
if (thread_setstatus(thread, ts_flavor, ts, ts_count) != KERN_SUCCESS) {
rval = EINVAL;
+#if DEVELOPMENT || DEBUG
+ printf("process %s[%d] sigreturn thread_setstatus error %d\n",
+ p->p_comm, p->p_pid, rval);
+#endif /* DEVELOPMENT || DEBUG */
goto error_ret;
}
if (thread_setstatus(thread, fs_flavor, fs, fs_count) != KERN_SUCCESS) {
rval = EINVAL;
+#if DEVELOPMENT || DEBUG
+ printf("process %s[%d] sigreturn thread_setstatus error %d\n",
+ p->p_comm, p->p_pid, rval);
+#endif /* DEVELOPMENT || DEBUG */
goto error_ret;
}
/*
- * machine_exception() performs MD translation
- * of a mach exception to a unix signal and code.
+ * machine_exception() performs machine-dependent translation
+ * of a mach exception to a unix signal.
*/
-
-boolean_t
-machine_exception(
- int exception,
- mach_exception_code_t code,
- __unused mach_exception_subcode_t subcode,
- int *unix_signal,
- mach_exception_code_t *unix_code)
+int
+machine_exception(int exception,
+ mach_exception_code_t code,
+ __unused mach_exception_subcode_t subcode)
{
-
switch(exception) {
-
- case EXC_BAD_ACCESS:
- /* Map GP fault to SIGSEGV, otherwise defer to caller */
- if (code == EXC_I386_GPFLT) {
- *unix_signal = SIGSEGV;
- *unix_code = code;
+ case EXC_BAD_ACCESS:
+ /* Map GP fault to SIGSEGV, otherwise defer to caller */
+ if (code == EXC_I386_GPFLT) {
+ return SIGSEGV;
+ }
break;
- }
- return(FALSE);
- case EXC_BAD_INSTRUCTION:
- *unix_signal = SIGILL;
- *unix_code = code;
- break;
+ case EXC_BAD_INSTRUCTION:
+ return SIGILL;
- case EXC_ARITHMETIC:
- *unix_signal = SIGFPE;
- *unix_code = code;
- break;
+ case EXC_ARITHMETIC:
+ return SIGFPE;
- case EXC_SOFTWARE:
- if (code == EXC_I386_BOUND) {
- /*
- * Map #BR, the Bound Range Exceeded exception, to
- * SIGTRAP.
- */
- *unix_signal = SIGTRAP;
- *unix_code = code;
+ case EXC_SOFTWARE:
+ if (code == EXC_I386_BOUND) {
+ /*
+ * Map #BR, the Bound Range Exceeded exception, to
+ * SIGTRAP.
+ */
+ return SIGTRAP;
+ }
break;
- }
-
- default:
- return(FALSE);
}
-
- return(TRUE);
+
+ return 0;
}
projects / apple / xnu.git / blobdiff