We shouldn't try to copy bytes beyond EOF. Fix it. Fixes: 9ded4a0114968e Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> Reviewed-by: Max Reitz <mre...@redhat.com> Reviewed-by: John Snow <js...@redhat.com> --- block/backup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/backup.c b/block/backup.c index db20249063..99177f03f8 100644 --- a/block/backup.c +++ b/block/backup.c @@ -161,7 +161,7 @@ static int coroutine_fn backup_cow_with_offload(BackupBlockJob *job, assert(QEMU_IS_ALIGNED(job->copy_range_size, job->cluster_size)); assert(QEMU_IS_ALIGNED(start, job->cluster_size)); - nbytes = MIN(job->copy_range_size, end - start); + nbytes = MIN(job->copy_range_size, MIN(end, job->len) - start); nr_clusters = DIV_ROUND_UP(nbytes, job->cluster_size); bdrv_reset_dirty_bitmap(job->copy_bitmap, start, job->cluster_size * nr_clusters); -- 2.21.0