linux-kernel - Re: powerpc: Keep const vars out of writable .sdata

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] [day] [month] [year] [list]

Message-Id: <3zwd2v0v8nz9shN@ozlabs.org>
Date:   Wed,  7 Mar 2018 00:31:17 +1100 (AEDT)
From:   Michael Ellerman <patch-notifications@...erman.id.au>
To:     Kees Cook <keescook@...omium.org>
Cc:     linux-kernel@...r.kernel.org, Paul Mackerras <paulus@...ba.org>,
        linuxppc-dev@...ts.ozlabs.org
Subject: Re: powerpc: Keep const vars out of writable .sdata

On Thu, 2018-03-01 at 01:02:49 UTC, Kees Cook wrote:
> From: Segher Boessenkool <segher@...nel.crashing.org>
> 
> Newer gcc will support "-mno-readonly-in-sdata"[1], which makes sure that
> the optimization on PPC32 for variables getting moved into the .sdata
> section will not apply to const variables (which must be in .rodata).
> 
> This was originally noticed in mm/rodata_test.c when rodata_test_data
> was not static:
> 
> c0695034 g     O .data	00000004 rodata_test_data
> 
> After this patch with an updated compiler, this is correctly in .rodata.
> 
> [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82411
> 
> Reported-by: Christophe Leroy <christophe.leroy@....fr>
> Signed-off-by: Segher Boessenkool <segher@...nel.crashing.org>
> Signed-off-by: Kees Cook <keescook@...omium.org>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/51d42f0f5fd6c74144d19bf6a66352

cheers