From patchwork Fri Nov 3 14:18:56 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alberto Garcia X-Patchwork-Id: 833895 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.b="ojwaTNmz"; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yT3yC3rsfz9s7p for ; Sat, 4 Nov 2017 01:20:19 +1100 (AEDT) Received: from localhost ([::1]:36906 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eAcpV-0002Pf-J7 for incoming@patchwork.ozlabs.org; Fri, 03 Nov 2017 10:20:17 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46071) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eAcon-0002Kt-1s for qemu-devel@nongnu.org; Fri, 03 Nov 2017 10:19:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eAcoi-0007up-0L for qemu-devel@nongnu.org; Fri, 03 Nov 2017 10:19:32 -0400 Received: from fanzine.igalia.com ([91.117.99.155]:38387) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1eAcoh-0007pS-J0; Fri, 03 Nov 2017 10:19:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=References:In-Reply-To:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=9sViIi9AFbn8+/akWCn/4dddv8+T++IkYyf99qoW9yo=; b=ojwaTNmzSC3F+hXJGrKYxaObfZXF6TWTvL2G9ytrunv4IgVZLMmg2Jzw8gYtjXyV4Zot2Z9tQohdzgEK/uDaTMCfxzdCjhzslBWmq5C8j0P2AzK/QY6AlwQJvw9eb/33bRU3nCuCARqbFWOR102rDOzvgd+Q1F/5obgHUSwuRa7vbVObvanwTqpwBbnks8t/KC1oDjOHwp7i6ZGZaR6StjDJ9Xj4lm2MIbXu0EIZZGgSYTEfOxgJv/6NjJuOtdj7k/TD+UHen6YzLjy+ej7OL7C+7dQH9oKRfZ+98ZvArY8mmhR8lQi0wTBtvZ73ZVwx1d3KuOOWQ2QQW400j2D2ow==; Received: from [194.100.51.2] (helo=perseus.local) by fanzine.igalia.com with esmtpsa (Cipher TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim) id 1eAcod-0004fP-0Y; Fri, 03 Nov 2017 15:19:23 +0100 Received: from berto by perseus.local with local (Exim 4.89) (envelope-from ) id 1eAcoK-0001KB-Nc; Fri, 03 Nov 2017 16:19:04 +0200 From: Alberto Garcia To: Date: Fri, 3 Nov 2017 16:18:56 +0200 Message-Id: X-Mailer: git-send-email 2.11.0 In-Reply-To: References: In-Reply-To: References: X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x (no timestamps) [generic] [fuzzy] X-Received-From: 91.117.99.155 Subject: [Qemu-devel] [PATCH v2 7/7] qcow2: Assert that the crypto header does not overlap other metadata 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: Thomas Huth , Alberto Garcia , qemu-block@nongnu.org, qemu-devel@nongnu.org, Max Reitz , "R . Nageswara Sastry" Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" The crypto header is initialized only when QEMU is creating a new image, so there's no chance of this happening on a corrupted image. If QEMU is really trying to allocate the header overlapping other existing metadata sections then this is a serious bug in QEMU itself so let's add an assertion. Signed-off-by: Alberto Garcia Reviewed-by: Daniel P. Berrange --- block/qcow2.c | 1 + 1 file changed, 1 insertion(+) diff --git a/block/qcow2.c b/block/qcow2.c index defc1fe49f..b3d66a0e88 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -126,6 +126,7 @@ static ssize_t qcow2_crypto_hdr_init_func(QCryptoBlock *block, size_t headerlen, /* Zero fill remaining space in cluster so it has predictable * content in case of future spec changes */ clusterlen = size_to_clusters(s, headerlen) * s->cluster_size; + assert(qcow2_pre_write_overlap_check(bs, 0, ret, clusterlen) == 0); ret = bdrv_pwrite_zeroes(bs->file, ret + headerlen, clusterlen - headerlen, 0);