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