signals: fix /sbin/init protection from unwanted signals

[net-next-2.6.git] / kernel / signal.c

diff --git a/kernel/signal.c b/kernel/signal.c
index 02ef3548aeb086b22b49b3cfa4d68819a9a1d5b5..646a8765696a1ea444c301569dfd67e195da60cd 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -728,7 +728,8 @@ static void complete_signal(int sig, struct task_struct *p, int group)
         * Found a killable thread.  If the signal will be fatal,
         * then start taking the whole group down immediately.
         */
-       if (sig_fatal(p, sig) && !(signal->flags & SIGNAL_GROUP_EXIT) &&
+       if (sig_fatal(p, sig) &&
+           !(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) &&
            !sigismember(&t->real_blocked, sig) &&
            (sig == SIGKILL || !(t->ptrace & PT_PTRACED))) {
                /*
@@ -1615,7 +1616,8 @@ static int do_signal_stop(int signr)
        } else {
                struct task_struct *t;
 
-               if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED) ||
+               if (unlikely((sig->flags & (SIGNAL_STOP_DEQUEUED | SIGNAL_UNKILLABLE))
+                                        != SIGNAL_STOP_DEQUEUED) ||
                    unlikely(signal_group_exit(sig)))
                        return 0;
                /*
@@ -1761,7 +1763,8 @@ relock:
                /*
                 * Global init gets no signals it doesn't want.
                 */
-               if (is_global_init(current))
+               if (unlikely(signal->flags & SIGNAL_UNKILLABLE) &&
+                   !signal_group_exit(signal))
                        continue;
 
                if (sig_kernel_stop(signr)) {