Patch "kernel/signal.c: protect the SIGNAL_UNKILLABLE tasks from !sig_kernel_only() signals" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

kernel/signal.c: protect the SIGNAL_UNKILLABLE tasks from !sig_kernel_only() signals

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
kernel-signal.c-protect-the-signal_unkillable-tasks-from-sig_kernel_only-signals.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Oleg Nesterov <[email protected]>
Date: Fri, 17 Nov 2017 15:30:04 -0800
Subject: kernel/signal.c: protect the SIGNAL_UNKILLABLE tasks from !sig_kernel_only() signals

From: Oleg Nesterov <[email protected]>

commit ac25385089f673560867eb5179228a44ade0cfc1 upstream.

Change sig_task_ignored() to drop the SIG_DFL && !sig_kernel_only() signals even if force == T. This simplifies the next change and this matches the same check in get_signal() which will drop these signals anyway.

---
 kernel/signal.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -72,7 +72,7 @@ static int sig_task_ignored(struct task_
 	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);

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/kernel-signal.c-remove-the-no-longer-needed-signal_unkillable-check-in-complete_signal.patch queue-4.9/kernel-signal.c-protect-the-signal_unkillable-tasks-from-sig_kernel_only-signals.patch queue-4.9/kernel-acct.c-fix-the-acct-needcheck-check-in-check_free_space.patch queue-4.9/kernel-signal.c-protect-the-traced-signal_unkillable-tasks-from-sigkill.patch