linux-kernel - Re: [PATCH] prctl_set_mm: downgrade mmap

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: <20190418140951.GH3040@uranus.lan>
Date:   Thu, 18 Apr 2019 17:09:51 +0300
From:   Cyrill Gorcunov <gorcunov@...il.com>
To:     Michal Koutný <mkoutny@...e.com>
Cc:     mhocko@...nel.org, akpm@...ux-foundation.org,
        arunks@...eaurora.org, brgl@...ev.pl, geert+renesas@...der.be,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        mguzik@...hat.com, rppt@...ux.ibm.com, vbabka@...e.cz,
        Laurent Dufour <ldufour@...ux.ibm.com>
Subject: Re: [PATCH] prctl_set_mm: downgrade mmap_sem to read lock

On Thu, Apr 18, 2019 at 03:50:39PM +0200, Michal Koutný wrote:
> I learnt, it's, alas, too late to drop the non PRCTL_SET_MM_MAP calls
> [1], so at least downgrade the write acquisition of mmap_sem as in the
> patch below (that should be stacked on the previous one or squashed).
> 
> Cyrill, you mentioned lock changes in [1] but the link seems empty. Is
> it supposed to be [2]? That could be an alternative to this patch after
> some refreshments and clarifications.

Yes, seems so. From a glance the patch shold be ok. Michal will review
it more carefully today. Thanks!