| From foo@baz Sat Nov 10 11:24:34 PST 2018 |
| From: "Eric W. Biederman" <ebiederm@xmission.com> |
| Date: Mon, 3 Sep 2018 20:02:46 +0200 |
| Subject: signal: Always deliver the kernel's SIGKILL and SIGSTOP to a pid namespace init |
| |
| From: "Eric W. Biederman" <ebiederm@xmission.com> |
| |
| [ 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@linutronix.de> |
| Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| kernel/signal.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/kernel/signal.c |
| +++ b/kernel/signal.c |
| @@ -991,7 +991,7 @@ static int __send_signal(int sig, struct |
| |
| 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 = group ? &t->signal->shared_pending : &t->pending; |