From nobody Tue Feb 10 10:04:19 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=virtuozzo.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 152943350629041.26087034236764; Tue, 19 Jun 2018 11:38:26 -0700 (PDT) Received: from localhost ([::1]:44397 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fVLWL-0001JE-G3 for importer@patchew.org; Tue, 19 Jun 2018 14:38:25 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47514) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fVLTB-0007ib-QV for qemu-devel@nongnu.org; Tue, 19 Jun 2018 14:35:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fVLTA-0005Zz-K5 for qemu-devel@nongnu.org; Tue, 19 Jun 2018 14:35:09 -0400 Received: from relay.sw.ru ([185.231.240.75]:38936) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fVLT4-0005Jk-Jx; Tue, 19 Jun 2018 14:35:02 -0400 Received: from msk-vpn.virtuozzo.com ([195.214.232.6] helo=kvm.sw.ru) by relay.sw.ru with esmtp (Exim 4.90_1) (envelope-from ) id 1fVLT2-0004dh-2x; Tue, 19 Jun 2018 21:35:00 +0300 From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org, qemu-devel@nongnu.org Date: Tue, 19 Jun 2018 21:34:56 +0300 Message-Id: <20180619183457.371081-7-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.11.1 In-Reply-To: <20180619183457.371081-1-vsementsov@virtuozzo.com> References: <20180619183457.371081-1-vsementsov@virtuozzo.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 185.231.240.75 Subject: [Qemu-devel] [PATCH 6/7] block/qcow2-refcount: fix out-of-file L1 entries to be zero 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: kwolf@redhat.com, den@openvz.org, vsementsov@virtuozzo.com, mreitz@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Zero out corrupted L1 table entry, which reference L2 table out of underlying file. Zero L1 table entry means that "the L2 table and all clusters described by this L2 table are unallocated." Signed-off-by: Vladimir Sementsov-Ogievskiy --- block/qcow2-refcount.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index d993252fb6..3c9e2da39e 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -1641,6 +1641,29 @@ static int fix_l2_entry_to_zero(BlockDriverState *bs= , BdrvCheckResult *res, return ret; } =20 +/* Zero out L1 entry + * + * Returns: -errno if overlap check failed + * 0 if write failed + * 1 on success + */ +static int fix_l1_entry_to_zero(BlockDriverState *bs, BdrvCheckResult *res, + BdrvCheckMode fix, int64_t l1_offset, + int l1_index, bool active, + const char *fmt, ...) +{ + int ret; + int ign =3D active ? QCOW2_OL_ACTIVE_L2 : QCOW2_OL_INACTIVE_L2; + va_list args; + + va_start(args, fmt); + ret =3D fix_table_entry(bs, res, fix, "L1", l1_offset, l1_index, 0, ig= n, + fmt, args); + va_end(args); + + return ret; +} + /* * Increases the refcount in the given refcount table for the all clusters * referenced in the L2 table. While doing so, performs some checks on L2 @@ -1837,6 +1860,20 @@ static int check_refcounts_l1(BlockDriverState *bs, if (l2_offset) { /* Mark L2 table as used */ l2_offset &=3D L1E_OFFSET_MASK; + if (l2_offset >=3D bdrv_getlength(bs->file->bs)) { + ret =3D fix_l1_entry_to_zero( + bs, res, fix, l1_table_offset, i, active, + "l2 table offset out of file: offset 0x%" PRIx64, + l2_offset); + if (ret < 0) { + /* Something is seriously wrong, so abort checking + * this L1 table */ + goto fail; + } + + continue; + } + ret =3D qcow2_inc_refcounts_imrt(bs, res, refcount_table, refcount_table_= size, l2_offset, s->cluster_size); --=20 2.11.1