From patchwork Tue Apr 5 03:43:55 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhanghailiang X-Patchwork-Id: 8746931 Return-Path: X-Original-To: patchwork-qemu-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 431F1C0553 for ; Tue, 5 Apr 2016 03:45:29 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id A208820204 for ; Tue, 5 Apr 2016 03:45:28 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A4A832017E for ; Tue, 5 Apr 2016 03:45:27 +0000 (UTC) Received: from localhost ([::1]:34196 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1anHvi-0000bQ-UV for patchwork-qemu-devel@patchwork.kernel.org; Mon, 04 Apr 2016 23:45:26 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33545) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1anHvb-0000bL-FB for qemu-devel@nongnu.org; Mon, 04 Apr 2016 23:45:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1anHvY-0007ux-Ph for qemu-devel@nongnu.org; Mon, 04 Apr 2016 23:45:19 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:38620) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1anHvW-0007oQ-DA for qemu-devel@nongnu.org; Mon, 04 Apr 2016 23:45:16 -0400 Received: from 172.24.1.50 (EHLO szxeml428-hub.china.huawei.com) ([172.24.1.50]) by szxrg01-dlp.huawei.com (MOS 4.3.7-GA FastPath queued) with ESMTP id DID48980; Tue, 05 Apr 2016 11:44:51 +0800 (CST) Received: from localhost (10.177.24.212) by szxeml428-hub.china.huawei.com (10.82.67.183) with Microsoft SMTP Server id 14.3.235.1; Tue, 5 Apr 2016 11:44:42 +0800 From: zhanghailiang To: Date: Tue, 5 Apr 2016 11:43:55 +0800 Message-ID: <1459827835-7524-1-git-send-email-zhang.zhanghailiang@huawei.com> X-Mailer: git-send-email 2.7.2.windows.1 MIME-Version: 1.0 X-Originating-IP: [10.177.24.212] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.570334B6.012A, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 5706c2ee9aae31ee096c1ff1277a53f4 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-Received-From: 58.251.152.64 Cc: jasowang@redhat.com, zhanghailiang Subject: [Qemu-devel] [PATCH v2] filter-buffer: fix segfault when starting qemu with status=off property X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP After commit 338d3f, we support 'status' property for filter object. The segfault can be triggered by starting qemu with 'status=off' property for filter, when the s->incoming_queue is NULL, we reference it directly in qemu_net_queue_flush() which was called in status_changed() callback function. We shouldn't trigger status_changed() before the filter was initialized, We can check the value of 'nf->netdev' to confirm if the filter is initialized or not, so let's check its value before calling status_changed(). Signed-off-by: zhanghailiang --- v2: - fix the segfault by skipping calling status_changed() if the filter is not initialized. (Jason Wang's suggestion) --- net/filter.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/filter.c b/net/filter.c index 1c4fc5a..8ac79f3 100644 --- a/net/filter.c +++ b/net/filter.c @@ -164,7 +164,7 @@ static void netfilter_set_status(Object *obj, const char *str, Error **errp) return; } nf->on = !nf->on; - if (nfc->status_changed) { + if (nf->netdev && nfc->status_changed) { nfc->status_changed(nf, errp); } }