From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 41E85C77B75 for ; Wed, 3 May 2023 16:03:24 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1puEv8-0004rQ-1J; Wed, 03 May 2023 12:01:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1puEuj-0004h2-JF for qemu-devel@nongnu.org; Wed, 03 May 2023 12:01:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1puEug-0002Mo-9u for qemu-devel@nongnu.org; Wed, 03 May 2023 12:01:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683129665; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UahQoPoQXJVF2UKfrCc72o8u6UvsnklGKPkLLGNR78I=; b=D4HYTmZqB9hJopB4Z+BboF1rbdSQnK0OY/2EKQeWGantcgt4W5ligzjsl50Q1pf62dwAdj WlIANI0bL0hK5cA+xBn7lXRZlXdBmCfiRe88tN7VsVIaDZLx/Hb/GCDRT1y/ukHws+QnCO aE2n4ua9ZZwpaGPM0kG8SpMUOM8Hyz0= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-659-asv2CEx5PK6v-Kx6geOoqA-1; Wed, 03 May 2023 12:01:03 -0400 X-MC-Unique: asv2CEx5PK6v-Kx6geOoqA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E91D588B77F; Wed, 3 May 2023 16:01:02 +0000 (UTC) Received: from localhost (unknown [10.39.193.0]) by smtp.corp.redhat.com (Postfix) with ESMTP id 64108C15BAD; Wed, 3 May 2023 16:01:02 +0000 (UTC) Date: Wed, 3 May 2023 12:01:00 -0400 From: Stefan Hajnoczi To: Kevin Wolf Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org Subject: Re: [PATCH] block: Fix use after free in blockdev_mark_auto_del() Message-ID: <20230503160100.GB10587@fedora> References: <20230503140142.474404-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="pf5RqCcbxBHvJlbp" Content-Disposition: inline In-Reply-To: <20230503140142.474404-1-kwolf@redhat.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.161, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org --pf5RqCcbxBHvJlbp Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, May 03, 2023 at 04:01:42PM +0200, Kevin Wolf wrote: > job_cancel_locked() drops the job list lock temporarily and it may call > aio_poll(). We must assume that the list has changed after this call. > Also, with unlucky timing, it can end up freeing the job during > job_completed_txn_abort_locked(), making the job pointer invalid, too. >=20 > For both reasons, we can't just continue at block_job_next_locked(job). > Instead, start at the head of the list again after job_cancel_locked() > and skip those jobs that we already cancelled (or that are completing > anyway). >=20 > Signed-off-by: Kevin Wolf > --- > blockdev.c | 18 ++++++++++++++---- > 1 file changed, 14 insertions(+), 4 deletions(-) Reviewed-by: Stefan Hajnoczi --pf5RqCcbxBHvJlbp Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmRShTwACgkQnKSrs4Gr c8gYCAf/VJBQlyUa8RkLnfJPMplOUgczkejL+xTxmNTtykmMThx2W4MM/L8Dc42y nffXcH6DPzNtW1XTC6+SFVReqn7N94ZD2ptjwoeFeUiSwx8dYnqQrWlXfKeC0KEW ZpqBCIqRnZKfg4lOVv5crX8rOL1LQI2PENUsOoaV7YBJzkDv/p3GlarudfBUeaTu IQ9za9RpjZg+xm/H8huhqnfrm13xsL1SXcmpSnWF/JCEcrDP5cag67xLuLMLQaRZ pSmwMM69plcDpqXdueXxfIQPKigNlq+/NPCB8GGmSTnPjqHvXYQL3guMRCUb3Swg 7g023lfPoua0Vlk1b92EgU8t0hnpGQ== =gL6M -----END PGP SIGNATURE----- --pf5RqCcbxBHvJlbp--