X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fsignal.c;h=82a3d924e7278b9ca5fde8338b4ed4102eaf68bc;hb=94b798ff0d7d4c30e38f9b61fc29fd17472221f9;hp=b3f78d09a1053b67f62719a8879f6619ae12253b;hpb=e0d65113a70f1dc514e625cc4e7a7485a4bf72df;p=pandora-kernel.git

diff --git a/kernel/signal.c b/kernel/signal.c
index b3f78d09a105..82a3d924e727 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -481,6 +481,9 @@ flush_signal_handlers(struct task_struct *t, int force_default)
 		if (force_default || ka->sa.sa_handler != SIG_IGN)
 			ka->sa.sa_handler = SIG_DFL;
 		ka->sa.sa_flags = 0;
+#ifdef __ARCH_HAS_SA_RESTORER
+		ka->sa.sa_restorer = NULL;
+#endif
 		sigemptyset(&ka->sa.sa_mask);
 		ka++;
 	}
@@ -532,7 +535,8 @@ unblock_all_signals(void)
 	spin_unlock_irqrestore(&current->sighand->siglock, flags);
 }
 
-static void collect_signal(int sig, struct sigpending *list, siginfo_t *info)
+static void collect_signal(int sig, struct sigpending *list, siginfo_t *info,
+			   bool *resched_timer)
 {
 	struct sigqueue *q, *first = NULL;
 
@@ -554,6 +558,12 @@ static void collect_signal(int sig, struct sigpending *list, siginfo_t *info)
 still_pending:
 		list_del_init(&first->list);
 		copy_siginfo(info, &first->info);
+
+		*resched_timer =
+			(first->flags & SIGQUEUE_PREALLOC) &&
+			(info->si_code == SI_TIMER) &&
+			(info->si_sys_private);
+
 		__sigqueue_free(first);
 	} else {
 		/*
@@ -570,7 +580,7 @@ still_pending:
 }
 
 static int __dequeue_signal(struct sigpending *pending, sigset_t *mask,
-			siginfo_t *info)
+			siginfo_t *info, bool *resched_timer)
 {
 	int sig = next_signal(pending, mask);
 
@@ -584,7 +594,7 @@ static int __dequeue_signal(struct sigpending *pending, sigset_t *mask,
 			}
 		}
 
-		collect_signal(sig, pending, info);
+		collect_signal(sig, pending, info, resched_timer);
 	}
 
 	return sig;
@@ -598,15 +608,16 @@ static int __dequeue_signal(struct sigpending *pending, sigset_t *mask,
  */
 int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
 {
+	bool resched_timer = false;
 	int signr;
 
 	/* We only dequeue private signals from ourselves, we don't let
 	 * signalfd steal them
 	 */
-	signr = __dequeue_signal(&tsk->pending, mask, info);
+	signr = __dequeue_signal(&tsk->pending, mask, info, &resched_timer);
 	if (!signr) {
 		signr = __dequeue_signal(&tsk->signal->shared_pending,
-					 mask, info);
+					 mask, info, &resched_timer);
 		/*
 		 * itimer signal ?
 		 *
@@ -651,7 +662,7 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
 		 */
 		current->jobctl |= JOBCTL_STOP_DEQUEUED;
 	}
-	if ((info->si_code & __SI_MASK) == __SI_TIMER && info->si_sys_private) {
+	if (resched_timer) {
 		/*
 		 * Release the siglock to ensure proper locking order
 		 * of timer locks outside of siglocks.  Note, we leave
@@ -676,23 +687,17 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
  * No need to set need_resched since signal event passing
  * goes through ->blocked
  */
-void signal_wake_up(struct task_struct *t, int resume)
+void signal_wake_up_state(struct task_struct *t, unsigned int state)
 {
-	unsigned int mask;
-
 	set_tsk_thread_flag(t, TIF_SIGPENDING);
-
 	/*
-	 * For SIGKILL, we want to wake it up in the stopped/traced/killable
+	 * TASK_WAKEKILL also means wake it up in the stopped/traced/killable
 	 * case. We don't check t->state here because there is a race with it
 	 * executing another processor and just now entering stopped state.
 	 * By using wake_up_state, we ensure the process will wake up and
 	 * handle its death signal.
 	 */
-	mask = TASK_INTERRUPTIBLE;
-	if (resume)
-		mask |= TASK_WAKEKILL;
-	if (!wake_up_state(t, mask))
+	if (!wake_up_state(t, state | TASK_INTERRUPTIBLE))
 		kick_process(t);
 }
 
@@ -841,7 +846,7 @@ static void ptrace_trap_notify(struct task_struct *t)
 	assert_spin_locked(&t->sighand->siglock);
 
 	task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY);
-	signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
+	ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
 }
 
 /*
@@ -1273,6 +1278,7 @@ struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
 
 	return sighand;
 }
+EXPORT_SYMBOL_GPL(__lock_task_sighand);
 
 /*
  * send signal info to all the members of a group
@@ -1610,6 +1616,15 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
 	BUG_ON(!tsk->ptrace &&
 	       (tsk->group_leader != tsk || !thread_group_empty(tsk)));
 
+	if (sig != SIGCHLD) {
+		/*
+		 * This is only possible if parent == real_parent.
+		 * Check if it has changed security domain.
+		 */
+		if (tsk->parent_exec_id != tsk->parent->self_exec_id)
+			sig = SIGCHLD;
+	}
+
 	info.si_signo = sig;
 	info.si_errno = 0;
 	/*
@@ -1756,6 +1771,10 @@ static inline int may_ptrace_stop(void)
 	 * If SIGKILL was already sent before the caller unlocked
 	 * ->siglock we must see ->core_state != NULL. Otherwise it
 	 * is safe to enter schedule().
+	 *
+	 * This is almost outdated, a task with the pending SIGKILL can't
+	 * block in TASK_TRACED. But PTRACE_EVENT_EXIT can be reported
+	 * after SIGKILL was already dequeued.
 	 */
 	if (unlikely(current->mm->core_state) &&
 	    unlikely(current->mm == current->parent->mm))
@@ -1881,6 +1900,7 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
 		if (gstop_done)
 			do_notify_parent_cldstop(current, false, why);
 
+		/* tasklist protects us from ptrace_freeze_traced() */
 		__set_current_state(TASK_RUNNING);
 		if (clear_code)
 			current->exit_code = 0;
@@ -1994,8 +2014,6 @@ static bool do_signal_stop(int signr)
 		 */
 		if (!(sig->flags & SIGNAL_STOP_STOPPED))
 			sig->group_exit_code = signr;
-		else
-			WARN_ON_ONCE(!current->ptrace);
 
 		sig->group_stop_count = 0;
 
@@ -2781,7 +2799,7 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
 
 static int do_tkill(pid_t tgid, pid_t pid, int sig)
 {
-	struct siginfo info;
+	struct siginfo info = {};
 
 	info.si_signo = sig;
 	info.si_errno = 0;