diff options
| author | Kevin Wolf <kwolf@redhat.com> | 2014-03-26 13:05:50 +0100 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2014-04-01 15:22:34 +0200 |
| commit | 2b5d5953eec0cc541857c3df812bdf8421596ab2 (patch) | |
| tree | 46005cfd30454c30b3e4853a8146e1ac260bee3c /block/qcow2.h | |
| parent | db8a31d11d6a60f48d6817530640d75aa72a9a2f (diff) | |
qcow2: Check new refcount table size on growth
If the size becomes larger than what qcow2_open() would accept, fail the
growing operation.
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/qcow2.h')
| -rw-r--r-- | block/qcow2.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/block/qcow2.h b/block/qcow2.h index b153505f5b..4015373bb0 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -40,6 +40,10 @@ #define QCOW_MAX_CRYPT_CLUSTERS 32 #define QCOW_MAX_SNAPSHOTS 65536 +/* 8 MB refcount 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_REFTABLE_SIZE 0x800000 + /* 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) */ @@ -410,6 +414,11 @@ static inline int64_t qcow2_vm_state_offset(BDRVQcowState *s) return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits); } +static inline uint64_t qcow2_max_refcount_clusters(BDRVQcowState *s) +{ + return QCOW_MAX_REFTABLE_SIZE >> s->cluster_bits; +} + static inline int qcow2_get_cluster_type(uint64_t l2_entry) { if (l2_entry & QCOW_OFLAG_COMPRESSED) { |