block: Detect multiplication overflow in bdrv_getlength

Bogus image may have a large total_sectors that will overflow the
multiplication. For cleanness, fix the return code so the error message
will be meaningful.

Reported-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Fam Zheng 2015-05-15 16:36:05 +08:00 committed by Kevin Wolf
parent b062ad86dc
commit 4a9c9ea0d3

View File

@ -2341,6 +2341,7 @@ int64_t bdrv_getlength(BlockDriverState *bs)
{
int64_t ret = bdrv_nb_sectors(bs);
ret = ret > INT64_MAX / BDRV_SECTOR_SIZE ? -EFBIG : ret;
return ret < 0 ? ret : ret * BDRV_SECTOR_SIZE;
}