Re: [PATCH 07/20] signal/powerpc: On swapcontext failure force SIGSEGV

From: Kees Cook
Date: Thu Oct 21 2021 - 12:09:48 EST


On Wed, Oct 20, 2021 at 12:43:53PM -0500, Eric W. Biederman wrote:
> If the register state may be partial and corrupted instead of calling
> do_exit, call force_sigsegv(SIGSEGV). Which properly kills the
> process with SIGSEGV and does not let any more userspace code execute,
> instead of just killing one thread of the process and potentially
> confusing everything.
>
> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
> Cc: Paul Mackerras <paulus@xxxxxxxxx>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> History-tree: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
> Fixes: 756f1ae8a44e ("PPC32: Rework signal code and add a swapcontext system call.")
> Fixes: 04879b04bf50 ("[PATCH] ppc64: VMX (Altivec) support & signal32 rework, from Ben Herrenschmidt")
> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>

This looks right to me.

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

--
Kees Cook