motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-06 01:03:55 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

qcow2: Check header_length (CVE-2014-0144)

Browse source 
This fixes an unbounded allocation for s->unknown_header_fields.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Kevin Wolf 2014-03-26 13:05:41 +01:00 • committed by Stefan Hajnoczi
parent 6d4b9e55fc
commit 24342f2cae
4 changed files with 96 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

34
block/qcow2.c
View file

@ -460,6 +460,18 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
s->qcow_version = header.version;
/* Initialise cluster size */
if (header.cluster_bits < MIN_CLUSTER_BITS ||
header.cluster_bits > MAX_CLUSTER_BITS) {
error_setg(errp, "Unsupported cluster size: 2^%i", header.cluster_bits);
ret = -EINVAL;
goto fail;
}
s->cluster_bits = header.cluster_bits;
s->cluster_size = 1 << s->cluster_bits;
s->cluster_sectors = 1 << (s->cluster_bits - 9);
/* Initialise version 3 header fields */
if (header.version == 2) {
header.incompatible_features = 0;
@ -473,6 +485,18 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
be64_to_cpus(&header.autoclear_features);
be32_to_cpus(&header.refcount_order);
be32_to_cpus(&header.header_length);
if (header.header_length < 104) {
error_setg(errp, "qcow2 header too short");
ret = -EINVAL;
goto fail;
}
}
if (header.header_length > s->cluster_size) {
error_setg(errp, "qcow2 header exceeds cluster size");
ret = -EINVAL;
goto fail;
}
if (header.header_length > sizeof(header)) {
@ -530,12 +554,6 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
}
s->refcount_order = header.refcount_order;
if (header.cluster_bits < MIN_CLUSTER_BITS ||
header.cluster_bits > MAX_CLUSTER_BITS) {
error_setg(errp, "Unsupported cluster size: 2^%i", header.cluster_bits);
ret = -EINVAL;
goto fail;
}
if (header.crypt_method > QCOW_CRYPT_AES) {
error_setg(errp, "Unsupported encryption method: %i",
header.crypt_method);
@ -546,9 +564,7 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
if (s->crypt_method_header) {
bs->encrypted = 1;
}
s->cluster_bits = header.cluster_bits;
s->cluster_size = 1 << s->cluster_bits;
s->cluster_sectors = 1 << (s->cluster_bits - 9);
s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */
s->l2_size = 1 << s->l2_bits;
bs->total_sectors = header.size / 512;