From 87cac542efd54bebd88396dfa79ed2ba9df5f42c Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Tue, 25 Mar 2014 11:45:24 +0100 Subject: [PATCH 06/48] qcow2: Validate active L1 table offset and size (CVE-2014-0144) RH-Author: Kevin Wolf Message-id: <1395744364-16049-6-git-send-email-kwolf@redhat.com> Patchwork-id: n/a O-Subject: [EMBARGOED RHEL-6.6/6.5.z qemu-kvm PATCH v2 05/45] qcow2: Validate active L1 table offset and size (CVE-2014-0144) Bugzilla: 1079453 RH-Acked-by: Max Reitz RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Jeff Cody Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1079453 Upstream status: Embargoed This avoids an unbounded allocation. Signed-off-by: Kevin Wolf Conflicts: tests/qemu-iotests/080 tests/qemu-iotests/080.out Signed-off-by: Kevin Wolf --- block/qcow2.c | 16 ++++++++++++++++ 1 files changed, 16 insertions(+), 0 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index faf0e22..4dbc212 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -293,6 +293,13 @@ static int qcow2_open(BlockDriverState *bs, int flags) s->nb_snapshots = header.nb_snapshots; /* read the level 1 table */ + if (header.l1_size > 0x2000000) { + /* 32 MB L1 table is enough for 2 PB images at 64k cluster size + * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */ + qerror_report(QERR_GENERIC_ERROR, "Active L1 table too large"); + ret = -EFBIG; + goto fail; + } s->l1_size = header.l1_size; s->l1_vm_state_index = size_to_l1(s, header.size); /* the L1 table must contain at least enough entries to put @@ -301,7 +308,16 @@ static int qcow2_open(BlockDriverState *bs, int flags) ret = -EINVAL; goto fail; } + + ret = validate_table_offset(bs, header.l1_table_offset, + header.l1_size, sizeof(uint64_t)); + if (ret < 0) { + qerror_report(QERR_GENERIC_ERROR, "Invalid L1 table offset"); + goto fail; + } s->l1_table_offset = header.l1_table_offset; + + if (s->l1_size > 0) { s->l1_table = g_malloc0( align_offset(s->l1_size * sizeof(uint64_t), 512)); -- 1.7.1