linux-kernel - Re: [PATCH 5/9] signal: Protect parent child relationships by childs siglock

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 for Android: free password hash cracker in your pocket

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

Message-ID: <87tuaebqdo.fsf@email.froward.int.ebiederm.org>
Date:   Wed, 27 Apr 2022 08:35:47 -0500
From:   "Eric W. Biederman" <ebiederm@...ssion.com>
To:     Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Cc:     linux-kernel@...r.kernel.org, rjw@...ysocki.net,
        Oleg Nesterov <oleg@...hat.com>, mingo@...nel.org,
        vincent.guittot@...aro.org, dietmar.eggemann@....com,
        rostedt@...dmis.org, mgorman@...e.de,
        Will Deacon <will@...nel.org>, tj@...nel.org,
        linux-pm@...r.kernel.org, Peter Zijlstra <peterz@...radead.org>,
        Richard Weinberger <richard@....at>,
        Anton Ivanov <anton.ivanov@...bridgegreys.com>,
        Johannes Berg <johannes@...solutions.net>,
        linux-um@...ts.infradead.org, Chris Zankel <chris@...kel.net>,
        Max Filippov <jcmvbkbc@...il.com>,
        inux-xtensa@...ux-xtensa.org, Kees Cook <keescook@...omium.org>,
        Jann Horn <jannh@...gle.com>
Subject: Re: [PATCH 5/9] signal: Protect parent child relationships by
 childs siglock

Sebastian Andrzej Siewior <bigeasy@...utronix.de> writes:

> On 2022-04-26 17:52:07 [-0500], Eric W. Biederman wrote:
>> The functions ptrace_stop and do_signal_stop have to drop siglock
>> and grab tasklist_lock because the parent/child relation ship
>> is guarded by siglock and not siglock.
>
>  "is guarded by tasklist_lock and not siglock." ?

Yes.   Thank you.  I will fix that.

>> Simplify things by guarding the parent/child relationship
>> with siglock.  For the most part this just requires a little bit
>> of code motion.  In a couple of places more locking was needed.
>> 
>> 
>> Signed-off-by: "Eric W. Biederman" <ebiederm@...ssion.com>
>
> Sebastian

Eric