Re: [PATCH 2/9] signal/seccomp: Refactor seccomp signal and coredump generation

From: Kees Cook
Date: Fri Jun 25 2021 - 23:17:57 EST


On Thu, Jun 24, 2021 at 01:59:55PM -0500, Eric W. Biederman wrote:
>
> Factor out force_sig_seccomp from the seccomp signal generation and
> place it in kernel/signal.c. The function force_sig_seccomp takes a
> paramter force_coredump to indicate that the sigaction field should be
> reset to SIGDFL so that a coredump will be generated when the signal
> is delivered.

Ah! This is the part I missed when I was originally trying to figure
out the coredump stuff. It's the need for setting a default handler
(i.e. doing a coredump)?

> force_sig_seccomp is then used to replace both seccomp_send_sigsys
> and seccomp_init_siginfo.
>
> force_sig_info_to_task gains an extra parameter to force using
> the default signal action.
>
> With this change seccomp is no longer a special case and there
> becomes exactly one place do_coredump is called from.

Looks good to me. This may benefit from force_sig_seccomp() to be wrapped
in an #ifdef CONFIG_SECCOMP.

(This patch reminds me that the seccomp self tests don't check for core
dumps...)

--
Kees Cook