From patchwork Mon Jul 31 10:21:29 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 9871499 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4B964603B4 for ; Mon, 31 Jul 2017 10:23:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3C20D28573 for ; Mon, 31 Jul 2017 10:23:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 30E7C285B9; Mon, 31 Jul 2017 10:23:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 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.wl.linuxfoundation.org (Postfix) with ESMTPS id A2D5928576 for ; Mon, 31 Jul 2017 10:23:19 +0000 (UTC) Received: from localhost ([::1]:58550 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dc7qm-00047q-FG for patchwork-qemu-devel@patchwork.kernel.org; Mon, 31 Jul 2017 06:23:00 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50904) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dc7pd-00046r-VI for qemu-devel@nongnu.org; Mon, 31 Jul 2017 06:21:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dc7pb-00069L-B2 for qemu-devel@nongnu.org; Mon, 31 Jul 2017 06:21:49 -0400 Received: from isrv.corpit.ru ([86.62.121.231]:32833) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dc7pb-00068X-30; Mon, 31 Jul 2017 06:21:47 -0400 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 341EF42ABF; Mon, 31 Jul 2017 13:21:46 +0300 (MSK) Received: from tls.msk.ru (mjt.vpn.tls.msk.ru [192.168.177.99]) by tsrv.corpit.ru (Postfix) with SMTP id 2691BB78; Mon, 31 Jul 2017 13:21:44 +0300 (MSK) Received: (nullmailer pid 5558 invoked by uid 1000); Mon, 31 Jul 2017 10:21:45 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Date: Mon, 31 Jul 2017 13:21:29 +0300 Message-Id: X-Mailer: git-send-email 2.11.0 In-Reply-To: References: In-Reply-To: References: MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 86.62.121.231 Subject: [Qemu-devel] [PULL 10/25] qcow2: fix null pointer dereference X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-trivial@nongnu.org, Michael Tokarev , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Philippe Mathieu-Daudé It seems this assert() was somehow misplaced. block/qcow2-refcount.c:2193:42: warning: Array access (from variable 'on_disk_reftable') results in a null pointer dereference on_disk_reftable[refblock_index] = refblock_offset; ~~~~~~~~~~~~~~~~ ^ Reported-by: Clang Static Analyzer Signed-off-by: Philippe Mathieu-Daudé Reviewed-by: Eric Blake Signed-off-by: Michael Tokarev --- block/qcow2-refcount.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index c9b0dcb4f3..168fc32e7b 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -2189,6 +2189,8 @@ write_refblocks: * this will leak that range, but we can easily fix that by running * a leak-fixing check after this rebuild operation */ reftable_offset = -1; + } else { + assert(on_disk_reftable); } on_disk_reftable[refblock_index] = refblock_offset; @@ -2258,8 +2260,6 @@ write_refblocks: goto write_refblocks; } - assert(on_disk_reftable); - for (refblock_index = 0; refblock_index < reftable_size; refblock_index++) { cpu_to_be64s(&on_disk_reftable[refblock_index]); }