Message ID | 1275065173-24045-14-git-send-email-kwolf@redhat.com |
---|---|
State | New |
Headers | show |
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 5b7cda4..22b0b45 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -417,6 +417,10 @@ static int write_refcount_block_entries(BlockDriverState *bs, return 0; } + if (first_index < 0) { + return 0; + } + first_index &= ~(REFCOUNTS_PER_SECTOR - 1); last_index = (last_index + REFCOUNTS_PER_SECTOR) & ~(REFCOUNTS_PER_SECTOR - 1);
After it is done with updating refcounts in the cache, update_refcount writes all changed entries to disk. If a refcount block allocation fails, however, there was no change yet and therefore first_index = last_index = -1. Don't treat -1 as a normal sector index (resulting in a 512 byte write!) but return without updating anything in this case. Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qcow2-refcount.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)