diff options
| author | Kevin Wolf <kwolf@redhat.com> | 2014-03-26 13:06:06 +0100 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2014-04-01 15:22:35 +0200 |
| commit | 6a83f8b5bec6f59e56cc49bd49e4c3f8f805d56f (patch) | |
| tree | 4063692109e5f06ece922daad860641ec0fe8421 /block | |
| parent | c05e4667be91b46ab42b5a11babf8e84d476cc6b (diff) | |
| download | qemu-6a83f8b5bec6f59e56cc49bd49e4c3f8f805d56f.zip qemu-6a83f8b5bec6f59e56cc49bd49e4c3f8f805d56f.tar.gz qemu-6a83f8b5bec6f59e56cc49bd49e4c3f8f805d56f.tar.bz2 | |
qcow2: Check maximum L1 size in qcow2_snapshot_load_tmp() (CVE-2014-0143)
This avoids an unbounded allocation.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/qcow2-snapshot.c | 4 | ||||
| -rw-r--r-- | block/qcow2.c | 4 | ||||
| -rw-r--r-- | block/qcow2.h | 4 |
3 files changed, 9 insertions, 3 deletions
diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index 715168e..5db4f30 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -680,6 +680,10 @@ int qcow2_snapshot_load_tmp(BlockDriverState *bs, sn = &s->snapshots[snapshot_index]; /* Allocate and read in the snapshot's L1 table */ + if (sn->l1_size > QCOW_MAX_L1_SIZE) { + error_setg(errp, "Snapshot L1 table too large"); + return -EFBIG; + } new_l1_bytes = sn->l1_size * sizeof(uint64_t); new_l1_table = g_malloc0(align_offset(new_l1_bytes, 512)); diff --git a/block/qcow2.c b/block/qcow2.c index be48a27..bb6000f 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -638,9 +638,7 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, } /* 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) */ + if (header.l1_size > QCOW_MAX_L1_SIZE) { error_setg(errp, "Active L1 table too large"); ret = -EFBIG; goto fail; diff --git a/block/qcow2.h b/block/qcow2.h index 3649465..f28e7d9 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -44,6 +44,10 @@ * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */ #define QCOW_MAX_REFTABLE_SIZE 0x800000 +/* 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) */ +#define QCOW_MAX_L1_SIZE 0x2000000 + /* indicate that the refcount of the referenced cluster is exactly one. */ #define QCOW_OFLAG_COPIED (1ULL << 63) /* indicate that the cluster is compressed (they never have the copied flag) */ |