qcow2: Prevent numerical overflow
authorMax Reitz <mreitz@redhat.com>
Tue, 2 Dec 2014 17:32:50 +0000 (18:32 +0100)
committerKevin Wolf <kwolf@redhat.com>
Wed, 10 Dec 2014 09:31:20 +0000 (10:31 +0100)
commit11c89769dc3e638ef72915d97058411ddf79b64b
treebf8c2026f009e60365e21ef398f04072c5630ec0
parent2247798d13e5295a097da0a42f9d0d70d88690a4
qcow2: Prevent numerical overflow

In qcow2_alloc_cluster_offset(), *num is limited to
INT_MAX >> BDRV_SECTOR_BITS by all callers. However, since remaining is
of type uint64_t, we might as well cast *num to that type before
performing the shift.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
block/qcow2-cluster.c