1 files changed, 10 insertions, 8 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index 5d50ea899b6d..4a548c6a4118 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -72,7 +72,7 @@ static int sig_task_ignored(struct task_struct *t, int sig, bool force)
         handler = sig_handler(t, sig);
 
         if (unlikely(t->signal->flags & SIGNAL_UNKILLABLE) &&
-                        handler == SIG_DFL && !force)
+            handler == SIG_DFL && !(force && sig_kernel_only(sig)))
                 return 1;
 
         return sig_handler_ignored(handler, sig);
@@ -88,13 +88,15 @@ static int sig_ignored(struct task_struct *t, int sig, bool force)
         if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig))
                 return 0;
 
-        if (!sig_task_ignored(t, sig, force))
-                return 0;
-
         /*
-         * Tracers may want to know about even ignored signals.
+         * Tracers may want to know about even ignored signal unless it
+         * is SIGKILL which can't be reported anyway but can be ignored
+         * by SIGNAL_UNKILLABLE task.
          */
-        return !t->ptrace;
+        if (t->ptrace && sig != SIGKILL)
+                return 0;
+
+        return sig_task_ignored(t, sig, force);
 }
 
 /*
@@ -917,9 +919,9 @@ static void complete_signal(int sig, struct task_struct *p, int group)
          * then start taking the whole group down immediately.
          */
         if (sig_fatal(p, sig) &&
-            !(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) &&
+            !(signal->flags & SIGNAL_GROUP_EXIT) &&
             !sigismember(&t->real_blocked, sig) &&
-            (sig == SIGKILL || !t->ptrace)) {
+            (sig == SIGKILL || !p->ptrace)) {
                 /*
                  * This signal will be fatal to the whole group.
                  */