linux-kernel - Re: [PATCH] drm/virtio: Fix GEM handle creation UAF

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]

Date:   Fri, 16 Dec 2022 15:50:22 -0800
From:   Chia-I Wu <olvaffe@...il.com>
To:     Rob Clark <robdclark@...il.com>
Cc:     dri-devel@...ts.freedesktop.org,
        Rob Clark <robdclark@...omium.org>,
        David Airlie <airlied@...hat.com>,
        Gerd Hoffmann <kraxel@...hat.com>,
        Gurchetan Singh <gurchetansingh@...omium.org>,
        Daniel Vetter <daniel@...ll.ch>,
        "open list:VIRTIO GPU DRIVER" 
        <virtualization@...ts.linux-foundation.org>,
        open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] drm/virtio: Fix GEM handle creation UAF

On Fri, Dec 16, 2022 at 3:33 PM Rob Clark <robdclark@...il.com> wrote:
>
> From: Rob Clark <robdclark@...omium.org>
>
> Userspace can guess the handle value and try to race GEM object creation
> with handle close, resulting in a use-after-free if we dereference the
> object after dropping the handle's reference.  For that reason, dropping
> the handle's reference must be done *after* we are done dereferencing
> the object.
>
> Signed-off-by: Rob Clark <robdclark@...omium.org>
Reviewed-by: Chia-I Wu <olvaffe@...il.com>