Subject: Re: [PATCH] entry: Fix boot for !CONFIG_GENERIC_ENTRY

From: Kees Cook <[email-masked]>
Date: Tue, 24 Nov 2020 13:45:42 -0800

On Mon, Nov 23, 2020 at 10:54:58AM -0500, Gabriel Krisman Bertazi wrote:
> Gabriel Krisman Bertazi <[email-masked]> writes:
> 
> > Jann Horn <[email-masked]> writes:
> >> As part of fixing this, it might be a good idea to put "enum
> >> syscall_work_bit" behind a "#ifdef CONFIG_GENERIC_ENTRY" to avoid
> >> future accidents like this?
> >
> > Hi Jan, Arnd,
> >
> > That is correct.  This is a copy pasta mistake.  My apologies.  I didn't
> > have a !GENERIC_ENTRY device to test, but just the ifdef would have
> > caught it.
> 
> I have patched it as suggested.  Tested on qemu for arm32 and on bare
> metal for x86-64.
> 
> Once again, my apologies for the mistake.
> 
> -- >8 --
> Subject: [PATCH] entry: Fix boot for !CONFIG_GENERIC_ENTRY
> 
> A copy-pasta mistake tries to set SYSCALL_WORK flags instead of TIF
> flags for !CONFIG_GENERIC_ENTRY.  Also, add safeguards to catch this at
> compilation time.
> 
> Reported-by: Naresh Kamboju <[email-masked]>
> Suggested-by: Jann Horn <[email-masked]>
> Signed-off-by: Gabriel Krisman Bertazi <[email-masked]>

Thanks for getting this fixed!

3136b93c3fb2 ("entry: Expose helpers to migrate TIF to SYSCALL_WORK flags")
Reviewed-by: Kees Cook <[email-masked]>

-- 
Kees Cook