Merge branch 'pcmcia' of git://git.linaro.org/people/rmk/linux-arm

[deliverable/linux.git] / kernel / signal.c

diff --git a/kernel/signal.c b/kernel/signal.c
index c73c4284160e1edd642a5fe2bd1d0067dca77539..d523da02dd14011188649e401de4ac36eaf43a58 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -58,21 +58,20 @@ static int sig_handler_ignored(void __user *handler, int sig)
                (handler == SIG_DFL && sig_kernel_ignore(sig));
 }
 
-static int sig_task_ignored(struct task_struct *t, int sig,
-               int from_ancestor_ns)
+static int sig_task_ignored(struct task_struct *t, int sig, bool force)
 {
        void __user *handler;
 
        handler = sig_handler(t, sig);
 
        if (unlikely(t->signal->flags & SIGNAL_UNKILLABLE) &&
-                       handler == SIG_DFL && !from_ancestor_ns)
+                       handler == SIG_DFL && !force)
                return 1;
 
        return sig_handler_ignored(handler, sig);
 }
 
-static int sig_ignored(struct task_struct *t, int sig, int from_ancestor_ns)
+static int sig_ignored(struct task_struct *t, int sig, bool force)
 {
        /*
         * Blocked signals are never ignored, since the
@@ -82,7 +81,7 @@ static int sig_ignored(struct task_struct *t, int sig, int from_ancestor_ns)
        if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig))
                return 0;
 
-       if (!sig_task_ignored(t, sig, from_ancestor_ns))
+       if (!sig_task_ignored(t, sig, force))
                return 0;
 
        /*
@@ -855,7 +854,7 @@ static void ptrace_trap_notify(struct task_struct *t)
  * Returns true if the signal should be actually delivered, otherwise
  * it should be dropped.
  */
-static int prepare_signal(int sig, struct task_struct *p, int from_ancestor_ns)
+static int prepare_signal(int sig, struct task_struct *p, bool force)
 {
        struct signal_struct *signal = p->signal;
        struct task_struct *t;
@@ -915,7 +914,7 @@ static int prepare_signal(int sig, struct task_struct *p, int from_ancestor_ns)
                }
        }
 
-       return !sig_ignored(p, sig, from_ancestor_ns);
+       return !sig_ignored(p, sig, force);
 }
 
 /*
@@ -1054,13 +1053,14 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
        struct sigpending *pending;
        struct sigqueue *q;
        int override_rlimit;
-
-       trace_signal_generate(sig, info, t);
+       int ret = 0, result;
 
        assert_spin_locked(&t->sighand->siglock);
 
-       if (!prepare_signal(sig, t, from_ancestor_ns))
-               return 0;
+       result = TRACE_SIGNAL_IGNORED;
+       if (!prepare_signal(sig, t,
+                       from_ancestor_ns || (info == SEND_SIG_FORCED)))
+               goto ret;
 
        pending = group ? &t->signal->shared_pending : &t->pending;
        /*
@@ -1068,8 +1068,11 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
         * exactly one non-rt signal, so that we can get more
         * detailed information about the cause of the signal.
         */
+       result = TRACE_SIGNAL_ALREADY_PENDING;
        if (legacy_queue(pending, sig))
-               return 0;
+               goto ret;
+
+       result = TRACE_SIGNAL_DELIVERED;
        /*
         * fast-pathed signals for kernel-internal things like SIGSTOP
         * or SIGKILL.
@@ -1127,14 +1130,15 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
                         * signal was rt and sent by user using something
                         * other than kill().
                         */
-                       trace_signal_overflow_fail(sig, group, info);
-                       return -EAGAIN;
+                       result = TRACE_SIGNAL_OVERFLOW_FAIL;
+                       ret = -EAGAIN;
+                       goto ret;
                } else {
                        /*
                         * This is a silent loss of information.  We still
                         * send the signal, but the *info bits are lost.
                         */
-                       trace_signal_lose_info(sig, group, info);
+                       result = TRACE_SIGNAL_LOSE_INFO;
                }
        }
 
@@ -1142,7 +1146,9 @@ out_set:
        signalfd_notify(t, sig);
        sigaddset(&pending->signal, sig);
        complete_signal(sig, t, group);
-       return 0;
+ret:
+       trace_signal_generate(sig, info, t, group, result);
+       return ret;
 }
 
 static int send_signal(int sig, struct siginfo *info, struct task_struct *t,
@@ -1585,7 +1591,7 @@ int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group)
        int sig = q->info.si_signo;
        struct sigpending *pending;
        unsigned long flags;
-       int ret;
+       int ret, result;
 
        BUG_ON(!(q->flags & SIGQUEUE_PREALLOC));
 
@@ -1594,7 +1600,8 @@ int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group)
                goto ret;
 
        ret = 1; /* the signal is ignored */
-       if (!prepare_signal(sig, t, 0))
+       result = TRACE_SIGNAL_IGNORED;
+       if (!prepare_signal(sig, t, false))
                goto out;
 
        ret = 0;
@@ -1605,6 +1612,7 @@ int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group)
                 */
                BUG_ON(q->info.si_code != SI_TIMER);
                q->info.si_overrun++;
+               result = TRACE_SIGNAL_ALREADY_PENDING;
                goto out;
        }
        q->info.si_overrun = 0;
@@ -1614,7 +1622,9 @@ int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group)
        list_add_tail(&q->list, &pending->list);
        sigaddset(&pending->signal, sig);
        complete_signal(sig, t, group);
+       result = TRACE_SIGNAL_DELIVERED;
 out:
+       trace_signal_generate(sig, &q->info, t, group, result);
        unlock_task_sighand(t, &flags);
 ret:
        return ret;
@@ -1642,6 +1652,15 @@ 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;
        /*