linux-kernel - Re: [PATCH 18/20] arm64: ptrace: handle ptrace_request differently for aarch32 and ilp32

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: <594D49E9.7090900@arm.com>
Date:   Fri, 23 Jun 2017 18:03:37 +0100
From:   James Morse <james.morse@....com>
To:     Yury Norov <ynorov@...iumnetworks.com>
CC:     Catalin Marinas <catalin.marinas@....com>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-doc@...r.kernel.org, Arnd Bergmann <arnd@...db.de>,
        Andrew Pinski <pinskia@...il.com>,
        Andrew Pinski <Andrew.Pinski@...iumnetworks.com>,
        Adam Borowski <kilobyte@...band.pl>,
        Chris Metcalf <cmetcalf@...hip.com>,
        Steve Ellcey <sellcey@...iumnetworks.com>,
        Maxim Kuvyrkov <maxim.kuvyrkov@...aro.org>,
        Ramana Radhakrishnan <ramana.gcc@...glemail.com>,
        Florian Weimer <fweimer@...hat.com>,
        Bamvor Zhangjian <bamvor.zhangjian@...wei.com>,
        Andreas Schwab <schwab@...e.de>,
        Chris Metcalf <cmetcalf@...lanox.com>,
        Heiko Carstens <heiko.carstens@...ibm.com>,
        schwidefsky@...ibm.com, broonie@...nel.org,
        Joseph Myers <joseph@...esourcery.com>,
        christoph.muellner@...obroma-systems.com, szabolcs.nagy@....com,
        klimov.linux@...il.com, Nathan_Lynch@...tor.com, agraf@...e.de,
        Prasun.Kapoor@...iumnetworks.com, geert@...ux-m68k.org,
        philipp.tomsich@...obroma-systems.com, manuel.montezelo@...il.com,
        linyongting@...wei.com, davem@...emloft.net,
        zhouchengming1@...wei.com,
        Bamvor Jian Zhang <bamvor.zhangjian@...aro.org>
Subject: Re: [PATCH 18/20] arm64: ptrace: handle ptrace_request differently
 for aarch32 and ilp32

Hi Yury,

On 04/06/17 13:00, Yury Norov wrote:
> ILP32 has context-related structures different from both aarch32 and
> aarch64/lp64. In this patch compat_arch_ptrace() renamed to
> compat_a32_ptrace(), and compat_arch_ptrace() only makes choice between
> compat_a32_ptrace() and new compat_ilp32_ptrace() handler.
> 
> compat_ilp32_ptrace() calls generic compat_ptrace_request() for all
> requests except PTRACE_GETSIGMASK and PTRACE_SETSIGMASK, which need
> special handling.

Can you elaborate on this special handling?

How come we don't need to wrap PTRACE_{G,S}ETSIGMASK for aarch32 compat?
>From kernel/signal32.c that uses compat_sigset_t too.

It looks like aarch64, ilp32 and aarch32 all use the same size sigset_t,
so doesn't compat_ptrace_request() already do everything we need?

...

Is this fixing an endian problem? If so, can we document it as such. Do we
already have the same bug for aarch32 compat?


Thanks,

James