From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> [ Upstream commit 3597dfe01d12f570bc739da67f857fd222a3ea66 ] Instead of playing whack-a-mole and changing SEND_SIG_PRIV to SEND_SIG_FORCED throughout the kernel to ensure a pid namespace init gets signals sent by the kernel, stop allowing a pid namespace init to ignore SIGKILL or SIGSTOP sent by the kernel. A pid namespace init is only supposed to be able to ignore signals sent from itself and children with SIG_DFL. Fixes: 921cf9f63089 ("signals: protect cinit from unblocked SIG_DFL signals") Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- kernel/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/signal.c b/kernel/signal.c index e4aad0e90882..092fb48ed845 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1035,7 +1035,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, result = TRACE_SIGNAL_IGNORED; if (!prepare_signal(sig, t, - from_ancestor_ns || (info == SEND_SIG_FORCED))) + from_ancestor_ns || (info == SEND_SIG_PRIV) || (info == SEND_SIG_FORCED))) goto ret; pending = (type != PIDTYPE_PID) ? &t->signal->shared_pending : &t->pending; -- 2.17.1