From patchwork Thu Jan 23 11:58:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Dr. David Alan Gilbert" X-Patchwork-Id: 1228017 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=Fp50R68w; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 483P7W6WjPz9sSL for ; Fri, 24 Jan 2020 01:00:55 +1100 (AEDT) Received: from localhost ([::1]:57568 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iud2T-0002nj-MH for incoming@patchwork.ozlabs.org; Thu, 23 Jan 2020 09:00:53 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:41862) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iubAr-0004MH-LI for qemu-devel@nongnu.org; Thu, 23 Jan 2020 07:01:27 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iubAq-0006mJ-Fq for qemu-devel@nongnu.org; Thu, 23 Jan 2020 07:01:25 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:25767 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iubAq-0006ll-Bn for qemu-devel@nongnu.org; Thu, 23 Jan 2020 07:01:24 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579780884; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=AsLIGnsc4Kc2PIcdInCoGUfJ3yiSTnFajKGCNhtMMv0=; b=Fp50R68w9+0k77d8o3EngYHiivBhLnTznZ7BhiF3cISvm5GLbknDr0hYFxYjknW/9wKzqN tmKc/arW0fXM3hoM22GkM1aIjYCbtYIHbIGlKOOy2bxTSCmyais4kfXXgO0hq0zelCBqlk FsQFhWedNC7sITiRazqlxNUmqGKSy7w= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-376-N0j0b-ElONKbHn6Jb4eQzg-1; Thu, 23 Jan 2020 07:01:22 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2A49818A6EC0 for ; Thu, 23 Jan 2020 12:01:21 +0000 (UTC) Received: from dgilbert-t580.localhost (unknown [10.36.118.0]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7576485754; Thu, 23 Jan 2020 12:01:20 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com Subject: [PULL 110/111] virtiofsd: stop all queue threads on exit in virtio_loop() Date: Thu, 23 Jan 2020 11:58:40 +0000 Message-Id: <20200123115841.138849-111-dgilbert@redhat.com> In-Reply-To: <20200123115841.138849-1-dgilbert@redhat.com> References: <20200123115841.138849-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: N0j0b-ElONKbHn6Jb4eQzg-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Eryu Guan On guest graceful shutdown, virtiofsd receives VHOST_USER_GET_VRING_BASE request from VMM and shuts down virtqueues by calling fv_set_started(), which joins fv_queue_thread() threads. So when virtio_loop() returns, there should be no thread is still accessing data in fuse session and/or virtio dev. But on abnormal exit, e.g. guest got killed for whatever reason, vhost-user socket is closed and virtio_loop() breaks out the main loop and returns to main(). But it's possible fv_queue_worker()s are still working and accessing fuse session and virtio dev, which results in crash or use-after-free. Fix it by stopping fv_queue_thread()s before virtio_loop() returns, to make sure there's no-one could access fuse session and virtio dev. Reported-by: Qingming Su Signed-off-by: Eryu Guan Reviewed-by: Stefan Hajnoczi Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/fuse_virtio.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c index 9f6582343c..80a6e929df 100644 --- a/tools/virtiofsd/fuse_virtio.c +++ b/tools/virtiofsd/fuse_virtio.c @@ -815,6 +815,19 @@ int virtio_loop(struct fuse_session *se) } } + /* + * Make sure all fv_queue_thread()s quit on exit, as we're about to + * free virtio dev and fuse session, no one should access them anymore. + */ + for (int i = 0; i < se->virtio_dev->nqueues; i++) { + if (!se->virtio_dev->qi[i]) { + continue; + } + + fuse_log(FUSE_LOG_INFO, "%s: Stopping queue %d thread\n", __func__, i); + fv_queue_cleanup_thread(se->virtio_dev, i); + } + fuse_log(FUSE_LOG_INFO, "%s: Exit\n", __func__); return 0;