linux-hardening - Re: [PATCH] powerpc/signal32: Use struct

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <202111221247.B385EA2A8@keescook>
Date:   Mon, 22 Nov 2021 12:47:28 -0800
From:   Kees Cook <keescook@...omium.org>
To:     Michael Ellerman <mpe@...erman.id.au>
Cc:     LEROY Christophe <christophe.leroy@...roup.eu>,
        kernel test robot <lkp@...el.com>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Sudeep Holla <sudeep.holla@....com>,
        Peter Zijlstra <peterz@...radead.org>,
        Nicholas Piggin <npiggin@...il.com>,
        "Aneesh Kumar K.V" <aneesh.kumar@...ux.ibm.com>,
        "Eric W. Biederman" <ebiederm@...ssion.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linuxppc-dev@...ts.ozlabs.org" <linuxppc-dev@...ts.ozlabs.org>,
        "linux-hardening@...r.kernel.org" <linux-hardening@...r.kernel.org>
Subject: Re: [PATCH] powerpc/signal32: Use struct_group() to zero spe regs

On Mon, Nov 22, 2021 at 04:43:36PM +1100, Michael Ellerman wrote:
> LEROY Christophe <christophe.leroy@...roup.eu> writes:
> > Le 18/11/2021 à 21:36, Kees Cook a écrit :
> >> In preparation for FORTIFY_SOURCE performing compile-time and run-time
> >> field bounds checking for memset(), avoid intentionally writing across
> >> neighboring fields.
> >> 
> >> Add a struct_group() for the spe registers so that memset() can correctly reason
> >> about the size:
> >> 
> >>     In function 'fortify_memset_chk',
> >>         inlined from 'restore_user_regs.part.0' at arch/powerpc/kernel/signal_32.c:539:3:
> >>     >> include/linux/fortify-string.h:195:4: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]
> >>       195 |    __write_overflow_field();
> >>           |    ^~~~~~~~~~~~~~~~~~~~~~~~
> >> 
> >> Reported-by: kernel test robot <lkp@...el.com>
> >> Signed-off-by: Kees Cook <keescook@...omium.org>
> >
> > Reviewed-by: Christophe Leroy <christophe.leroy@...roup.eu>
> 
> Acked-by: Michael Ellerman <mpe@...erman.id.au>

Thanks! Should I take this via my tree, or do you want to take it via
ppc?

-Kees

-- 
Kees Cook