diff options
| -rw-r--r-- | block/qcow2-refcount.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index c974abe795..8712d8bd54 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -676,7 +676,13 @@ int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset, BDRVQcowState *s = bs->opaque; uint64_t cluster_index; uint64_t old_free_cluster_index; - int i, refcount, ret; + uint64_t i; + int refcount, ret; + + assert(nb_clusters >= 0); + if (nb_clusters == 0) { + return 0; + } /* Check how many clusters there are free */ cluster_index = offset >> s->cluster_bits; |