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 84C44C05027 for ; Fri, 10 Feb 2023 14:34:19 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pQUSK-00038H-0w; Fri, 10 Feb 2023 09:32:52 -0500 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 1pQUSI-00037r-QY for qemu-devel@nongnu.org; Fri, 10 Feb 2023 09:32:50 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pQUSG-00019O-55 for qemu-devel@nongnu.org; Fri, 10 Feb 2023 09:32:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1676039567; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=x0IgjbxkT8osxJncygB6TmpjSUYB81tFay7Rjvv8Ujo=; b=VIojEEJ5uP0BQaRUgjUT+BxvgROsaEvYdqB+cm1nR2xtSZtCktOlTPWYWnfTbYODFNsbAB WvZRwxDaF57wNanD1ynX2RGXjHvppHXUEH8Tke9S3NP2Q41+7ePQe44WOIVUElyHZpZgEk ZJo6ngXF1hCEdcAxw7fOank+E8DBe+g= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-138-fZ_NeD1xPmm0CwkfiyQGLA-1; Fri, 10 Feb 2023 09:32:44 -0500 X-MC-Unique: fZ_NeD1xPmm0CwkfiyQGLA-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2303D1C05191; Fri, 10 Feb 2023 14:32:44 +0000 (UTC) Received: from localhost (unknown [10.39.192.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7F1FC492B00; Fri, 10 Feb 2023 14:32:43 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: , "Michael S. Tsirkin" , Paolo Bonzini , David Hildenbrand , Peter Xu , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Fam Zheng , Stefan Hajnoczi Subject: [PATCH v2 1/3] scsi: protect req->aiocb with AioContext lock Date: Fri, 10 Feb 2023 09:32:36 -0500 Message-Id: <20230210143238.524357-2-stefanha@redhat.com> In-Reply-To: <20230210143238.524357-1-stefanha@redhat.com> References: <20230210143238.524357-1-stefanha@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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 autolearn=unavailable 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 If requests are being processed in the IOThread when a SCSIDevice is unplugged, scsi_device_purge_requests() -> scsi_req_cancel_async() races with I/O completion callbacks. Both threads load and store req->aiocb. This can lead to assert(r->req.aiocb == NULL) failures and undefined behavior. Protect r->req.aiocb with the AioContext lock to prevent the race. Signed-off-by: Stefan Hajnoczi --- hw/scsi/scsi-disk.c | 23 ++++++++++++++++------- hw/scsi/scsi-generic.c | 11 ++++++----- 2 files changed, 22 insertions(+), 12 deletions(-) diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index d4e360850f..115584f8b9 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -273,9 +273,11 @@ static void scsi_aio_complete(void *opaque, int ret) SCSIDiskReq *r = (SCSIDiskReq *)opaque; SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); + aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + if (scsi_disk_req_check_error(r, ret, true)) { goto done; } @@ -357,10 +359,11 @@ static void scsi_dma_complete(void *opaque, int ret) SCSIDiskReq *r = (SCSIDiskReq *)opaque; SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); + aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); if (ret < 0) { block_acct_failed(blk_get_stats(s->qdev.conf.blk), &r->acct); } else { @@ -393,10 +396,11 @@ static void scsi_read_complete(void *opaque, int ret) SCSIDiskReq *r = (SCSIDiskReq *)opaque; SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); + aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); if (ret < 0) { block_acct_failed(blk_get_stats(s->qdev.conf.blk), &r->acct); } else { @@ -446,10 +450,11 @@ static void scsi_do_read_cb(void *opaque, int ret) SCSIDiskReq *r = (SCSIDiskReq *)opaque; SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); + aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + assert (r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); if (ret < 0) { block_acct_failed(blk_get_stats(s->qdev.conf.blk), &r->acct); } else { @@ -530,10 +535,11 @@ static void scsi_write_complete(void * opaque, int ret) SCSIDiskReq *r = (SCSIDiskReq *)opaque; SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); + aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + assert (r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); if (ret < 0) { block_acct_failed(blk_get_stats(s->qdev.conf.blk), &r->acct); } else { @@ -1737,10 +1743,11 @@ static void scsi_unmap_complete(void *opaque, int ret) SCSIDiskReq *r = data->r; SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); + aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); if (scsi_disk_req_check_error(r, ret, true)) { scsi_req_unref(&r->req); g_free(data); @@ -1816,9 +1823,11 @@ static void scsi_write_same_complete(void *opaque, int ret) SCSIDiskReq *r = data->r; SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev); + aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->qdev.conf.blk)); + if (scsi_disk_req_check_error(r, ret, true)) { goto done; } diff --git a/hw/scsi/scsi-generic.c b/hw/scsi/scsi-generic.c index 92cce20a4d..ac9fa662b4 100644 --- a/hw/scsi/scsi-generic.c +++ b/hw/scsi/scsi-generic.c @@ -111,10 +111,11 @@ static void scsi_command_complete(void *opaque, int ret) SCSIGenericReq *r = (SCSIGenericReq *)opaque; SCSIDevice *s = r->req.dev; + aio_context_acquire(blk_get_aio_context(s->conf.blk)); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->conf.blk)); scsi_command_complete_noio(r, ret); aio_context_release(blk_get_aio_context(s->conf.blk)); } @@ -269,11 +270,11 @@ static void scsi_read_complete(void * opaque, int ret) SCSIDevice *s = r->req.dev; int len; + aio_context_acquire(blk_get_aio_context(s->conf.blk)); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->conf.blk)); - if (ret || r->req.io_canceled) { scsi_command_complete_noio(r, ret); goto done; @@ -386,11 +387,11 @@ static void scsi_write_complete(void * opaque, int ret) trace_scsi_generic_write_complete(ret); + aio_context_acquire(blk_get_aio_context(s->conf.blk)); + assert(r->req.aiocb != NULL); r->req.aiocb = NULL; - aio_context_acquire(blk_get_aio_context(s->conf.blk)); - if (ret || r->req.io_canceled) { scsi_command_complete_noio(r, ret); goto done; -- 2.39.1