From: Konstantin Khorenko <khorenko@virtuozzo.com>
To: Alexander Ivanov <alexander.ivanov@virtuozzo.com>,
andrey.zhadchenko@virtuozzo.com
Cc: devel@openvz.org
Subject: Re: [Devel] [PATCH hci-8.1] drivers/vhost/blk: reject a head that is still in flight
Date: Thu, 29 Oct 2026 13:05:52 +0100 [thread overview]
Message-ID: <95e43d78-0b02-4f4b-9f01-2a8d4d63488b@virtuozzo.com> (raw)
In-Reply-To: <20261028081459.3050162-1-alexander.ivanov@virtuozzo.com>
--
Best regards,
Konstantin Khorenko,
Virtuozzo Linux Kernel Team
On 10/28/26 09:14, Alexander Ivanov wrote:
> The second
> submission also overwrites bio[], bio_nr and the iovecs of bios that
> are still in flight.
It also frees the bounce buffer and bio[] of the first submission under
bios that are still in flight, so this is a use-after-free, not only a
counter leak. Worth a sentence here.
> + if (unlikely(req->inflight))
> + return -EBUSY;
Please add a vhostblk_vq_err() here naming the head. Now the host log
only shows the caller's generic "Failed to process guest request" with
-16.
A separate ticket, not for this patch: vhost_blk_req_done() ignores a
failed vhost_vq_work_queue(). After vhost_worker_killed() (QEMU
SIGKILLed with bios in flight) vq->worker is NULL, the completion is
lost, forget_request() never runs and release hangs in
vhost_blk_flush() the same way.
Please file a ticket an post it here for the reference.
Reviewed-by: Konstantin Khorenko <khorenko@virtuozzo.com>
--
Best regards,
Konstantin Khorenko,
Virtuozzo Linux Kernel Team
_______________________________________________
Devel mailing list
Devel@openvz.org
https://lists.openvz.org/mailman/listinfo/devel
next prev parent reply other threads:[~2026-10-29 12:07 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-28 8:14 Alexander Ivanov
2026-10-29 11:03 ` Andrey Zhadchenko
2026-10-29 12:05 ` Konstantin Khorenko [this message]
2026-10-29 13:43 ` Alexander Ivanov
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=95e43d78-0b02-4f4b-9f01-2a8d4d63488b@virtuozzo.com \
--to=khorenko@virtuozzo.com \
--cc=alexander.ivanov@virtuozzo.com \
--cc=andrey.zhadchenko@virtuozzo.com \
--cc=devel@openvz.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox