From patchwork Fri Sep 30 10:53:19 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vladimir Sementsov-Ogievskiy X-Patchwork-Id: 676976 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org 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 3slpjd6WJ5z9ryQ for ; Fri, 30 Sep 2016 21:14:13 +1000 (AEST) Received: from localhost ([::1]:43258 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bpvla-0005q6-A7 for incoming@patchwork.ozlabs.org; Fri, 30 Sep 2016 07:14:10 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53583) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bpvRm-0003ZF-8j for qemu-devel@nongnu.org; Fri, 30 Sep 2016 06:53:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bpvRi-00008v-5m for qemu-devel@nongnu.org; Fri, 30 Sep 2016 06:53:41 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:10237 helo=relay.sw.ru) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bpvRh-00005m-Nj for qemu-devel@nongnu.org; Fri, 30 Sep 2016 06:53:38 -0400 Received: from kvm.qa.sw.ru. ([10.28.8.145]) by relay.sw.ru (8.13.4/8.13.4) with ESMTP id u8UArVlg029823; Fri, 30 Sep 2016 13:53:32 +0300 (MSK) From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org, qemu-devel@nongnu.org Date: Fri, 30 Sep 2016 13:53:19 +0300 Message-Id: <1475232808-4852-14-git-send-email-vsementsov@virtuozzo.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1475232808-4852-1-git-send-email-vsementsov@virtuozzo.com> References: <1475232808-4852-1-git-send-email-vsementsov@virtuozzo.com> X-detected-operating-system: by eggs.gnu.org: OpenBSD 3.x X-Received-From: 195.214.232.25 Subject: [Qemu-devel] [PATCH 13/22] qcow2-bitmap: check constraints 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, vsementsov@virtuozzo.com, famz@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, pbonzini@redhat.com, den@openvz.org, jsnow@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Check bitmap header constraints as specified in docs/specs/qcow2.txt Signed-off-by: Vladimir Sementsov-Ogievskiy --- block/qcow2-bitmap.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c index 8cf40f0..1c3abea 100644 --- a/block/qcow2-bitmap.c +++ b/block/qcow2-bitmap.c @@ -154,6 +154,34 @@ static inline void bitmap_directory_to_be(uint8_t *dir, size_t size) } } +static int check_constraints(BlockDriverState *bs, Qcow2BitmapDirEntry *h) +{ + BDRVQcow2State *s = bs->opaque; + uint64_t phys_bitmap_bytes = + (uint64_t)h->bitmap_table_size * s->cluster_size; + uint64_t max_virtual_bits = (phys_bitmap_bytes * 8) << h->granularity_bits; + int64_t nb_sectors = bdrv_nb_sectors(bs); + + if (nb_sectors < 0) { + return nb_sectors; + } + + int fail = + ((h->bitmap_table_size == 0) != (h->bitmap_table_offset == 0)) || + (h->bitmap_table_offset % s->cluster_size) || + (h->bitmap_table_size > BME_MAX_TABLE_SIZE) || + (phys_bitmap_bytes > BME_MAX_PHYS_SIZE) || + (h->bitmap_table_offset != 0 && + (nb_sectors << BDRV_SECTOR_BITS) > max_virtual_bits) || + (h->granularity_bits > BME_MAX_GRANULARITY_BITS) || + (h->granularity_bits < BME_MIN_GRANULARITY_BITS) || + (h->flags & BME_RESERVED_FLAGS) || + (h->name_size > BME_MAX_NAME_SIZE) || + (h->type != BT_DIRTY_TRACKING_BITMAP); + + return fail ? -EINVAL : 0; +} + static void clear_bitmap_table(BlockDriverState *bs, uint64_t *bitmap_table, uint32_t bitmap_table_size) { @@ -372,6 +400,12 @@ static uint8_t *directory_read(BlockDriverState *bs, bdrv_get_device_or_node_name(bs)); goto fail; } + + ret = check_constraints(bs, e); + if (ret < 0) { + error_setg(errp, "Bitmap doesn't satisfy the constraints."); + goto fail; + } } assert((uint8_t *)e == dir_end); @@ -713,6 +747,11 @@ static int store_bitmap(BlockDriverState *bs, entry->extra_data_size = 0; memcpy(entry + 1, bm_name, entry->name_size); + ret = check_constraints(bs, entry); + if (ret < 0) { + goto fail; + } + return 0; fail: