dm-pcache: bound the logical key offset from persistent memory

cache_key_decode() takes a key's logical off from the cache device and
later indexes req_key_tree->subtrees[] by it in get_subtree(). An off
past the device forms a subtree pointer outside the array, which
rb_insert() writes through during replay.

Reject a key of zero length, or whose off+len (computed in 64 bits)
exceeds the device size, before it is used.

Fixes: 1d57628ff95b ("dm-pcache: add persistent cache target in device-mapper")
Cc: stable@vger.kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

0 files changed, 0 insertions, 0 deletions