4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oleg Nesterov <oleg@xxxxxxxxxx> 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. Link: http://lkml.kernel.org/r/20171103184227.GC21036@xxxxxxxxxx Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Tested-by: Kyle Huey <me@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/signal.c +++ b/kernel/signal.c @@ -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);