On Wed, Apr 24, 2019 at 08:52:38PM +0800, Zhenliang Wei wrote:

In the fixes commit, removing SIGKILL from each thread signal mask and executing "goto fatal" directly will skip the call to "trace_signal_deliver". At this point, the delivery tracking of the SIGKILL signal will be inaccurate.

Therefore, we need to add trace_signal_deliver before "goto fatal" after executing sigdelset.

Note: SEND_SIG_NOINFO matches the fact that SIGKILL doesn't have any info.

Acked-by: Christian Brauner christian@brauner.io

I think we're supposed to use more Reviewed-bys so feel free (or Andrew) to change this to:

Reviewed-by: Christian Brauner christian@brauner.io

Reviewed-by: Oleg Nesterov oleg@redhat.com Cc: stable@vger.kernel.org Fixes: cf43a757fd4944 ("signal: Restore the stop PTRACE_EVENT_EXIT") Reported-by: kbuild test robot lkp@intel.com Signed-off-by: Zhenliang Wei weizhenliang@huawei.com

---

kernel/signal.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/kernel/signal.c b/kernel/signal.c index 227ba170298e..3edf526db7c6 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2441,6 +2441,8 @@ bool get_signal(struct ksignal *ksig) if (signal_group_exit(signal)) { ksig->info.si_signo = signr = SIGKILL; sigdelset(&current->pending.signal, SIGKILL);

• trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO,
  

• 	&sighand->action[signr - 1]);
  

Hm, sorry for being the really nitpicky person here. Just for the sake of consistency how about we do either:

+ trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, + &sighand->action[SIGKILL - 1]);

or

+ trace_signal_deliver(signr, SEND_SIG_NOINFO, + &sighand->action[signr - 1]);

I'm not going to argue about this though. Can just also leave it as is.

Christian