All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stefan Hajnoczi <stefanha@gmail.com>
To: gerben@altlinux.org
Cc: qemu-devel@nongnu.org, kwolf@redhat.com, hreitz@redhat.com,
	sdl.qemu@linuxtesting.org
Subject: Re: [PATCH] block/qed: fix use-after-free by nullifying timer pointer after free
Date: Thu, 6 Mar 2025 10:21:42 +0800	[thread overview]
Message-ID: <20250306022142.GA304567@fedora> (raw)
In-Reply-To: <20250304083927.37681-1-gerben@altlinux.org>

[-- Attachment #1: Type: text/plain, Size: 833 bytes --]

On Tue, Mar 04, 2025 at 11:39:10AM +0300, gerben@altlinux.org wrote:
> From: Denis Rastyogin <gerben@altlinux.org>
> 
> This error was discovered by fuzzing qemu-img.
> 
> In the QED block driver, the need_check_timer timer is freed in
> bdrv_qed_detach_aio_context, but the pointer to the timer is not
> set to NULL. This can lead to a use-after-free scenario
> in bdrv_qed_drain_begin().
> 
> The need_check_timer pointer is set to NULL after freeing the timer.
> Which helps catch this condition when checking in bdrv_qed_drain_begin().
> 
> Closes: https://gitlab.com/qemu-project/qemu/-/issues/2852
> Signed-off-by: Denis Rastyogin <gerben@altlinux.org>
> ---
>  block/qed.c | 1 +
>  1 file changed, 1 insertion(+)

Thanks, applied to my block tree:
https://gitlab.com/stefanha/qemu/commits/block

Stefan

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

      reply	other threads:[~2025-03-06  2:22 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-03-04  8:39 [PATCH] block/qed: fix use-after-free by nullifying timer pointer after free gerben
2025-03-06  2:21 ` Stefan Hajnoczi [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20250306022142.GA304567@fedora \
    --to=stefanha@gmail.com \
    --cc=gerben@altlinux.org \
    --cc=hreitz@redhat.com \
    --cc=kwolf@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=sdl.qemu@linuxtesting.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.