From: yuchenlin <yuchen...@synology.com> VMDK has a hard limitation of extent size, which is due to the size of grain table entry is 32 bits. It means it can only point to a grain located at offset = 2^32. To avoid writing the user data beyond limitation and record a useless offset in grain table. We should return ERROR here.
Signed-off-by: yuchenlin <yuchen...@synology.com> Message-id: 20180322133337.28024-1-yuchen...@synology.com Reviewed-by: Fam Zheng <f...@redhat.com> Signed-off-by: Max Reitz <mre...@redhat.com> --- block/vmdk.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/block/vmdk.c b/block/vmdk.c index f94c49a9c0..84f8bbe480 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -47,6 +47,8 @@ #define VMDK4_FLAG_MARKER (1 << 17) #define VMDK4_GD_AT_END 0xffffffffffffffffULL +#define VMDK_EXTENT_MAX_SECTORS (1ULL << 32) + #define VMDK_GTE_ZEROED 0x1 /* VMDK internal error codes */ @@ -1250,6 +1252,10 @@ static int get_cluster_offset(BlockDriverState *bs, return zeroed ? VMDK_ZEROED : VMDK_UNALLOC; } + if (extent->next_cluster_sector >= VMDK_EXTENT_MAX_SECTORS) { + return VMDK_ERROR; + } + cluster_sector = extent->next_cluster_sector; extent->next_cluster_sector += extent->cluster_sectors; -- 2.14.3