This fixes the bug introduced by commit c6ac36e (vmdk: Optimize cluster allocation).
Sometimes, write_len could be larger than cluster size, because it contains both data and marker. We must advance next_cluster_sector in this case, otherwise the image gets corrupted. Reported-by: Antoni Villalonga <qemu-l...@friki.cat> Signed-off-by: Fam Zheng <f...@redhat.com> --- block/vmdk.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index 1c5e2ef..4b4a862 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -1302,6 +1302,8 @@ static int vmdk_write_extent(VmdkExtent *extent, int64_t cluster_offset, uLongf buf_len; const uint8_t *write_buf = buf; int write_len = nb_sectors * 512; + int64_t write_offset; + int64_t write_end_sector; if (extent->compressed) { if (!extent->has_marker) { @@ -1320,10 +1322,14 @@ static int vmdk_write_extent(VmdkExtent *extent, int64_t cluster_offset, write_buf = (uint8_t *)data; write_len = buf_len + sizeof(VmdkGrainMarker); } - ret = bdrv_pwrite(extent->file, - cluster_offset + offset_in_cluster, - write_buf, - write_len); + write_offset = cluster_offset + offset_in_cluster, + ret = bdrv_pwrite(extent->file, write_offset, write_buf, write_len); + + write_end_sector = DIV_ROUND_UP(write_offset + write_len, BDRV_SECTOR_SIZE); + + extent->next_cluster_sector = MAX(extent->next_cluster_sector, + write_end_sector); + if (ret != write_len) { ret = ret < 0 ? ret : -EIO; goto out; -- 1.9.3