Re: [PATCH v3] signal: trace_signal_deliver when signal_group_exit

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Apr 22, 2019 at 10:59:50PM +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: The action[SIGKILL] must be SIG_DFL, and SEND_SIG_NOINFO matches
> the fact that SIGKILL doesn't have any info.
> 
> Acked-by: Christian Brauner <christian@brauner.io>
> Fixes: cf43a757fd4944 ("signal: Restore the stop PTRACE_EVENT_EXIT")
> Signed-off-by: Zhenliang Wei <weizhenliang@huawei.com>
> ---
>  kernel/signal.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/signal.c b/kernel/signal.c
> index 227ba170298e..0f69ada376ef 100644
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -2441,6 +2441,7 @@ 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, SIG_DFL);
>  		recalc_sigpending();
>  		goto fatal;
>  	}
> -- 
> 2.14.1.windows.1
> 
> 

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>