]> git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/commit
loop: add recursion validation to LOOP_CHANGE_FD
authorTheodore Ts'o <tytso@mit.edu>
Mon, 7 May 2018 15:37:58 +0000 (11:37 -0400)
committerJens Axboe <axboe@kernel.dk>
Tue, 5 Jun 2018 15:08:21 +0000 (09:08 -0600)
commitd2ac838e4cd7e5e9891ecc094d626734b0245c99
treeb93df5a59844ad585b25dad0ee85890a2cc0fbae
parentd377535405686f735b90a8ad4ba269484cd7c96e
loop: add recursion validation to LOOP_CHANGE_FD

Refactor the validation code used in LOOP_SET_FD so it is also used in
LOOP_CHANGE_FD.  Otherwise it is possible to construct a set of loop
devices that all refer to each other.  This can lead to a infinite
loop in starting with "while (is_loop_device(f)) .." in loop_set_fd().

Fix this by refactoring out the validation code and using it for
LOOP_CHANGE_FD as well as LOOP_SET_FD.

Reported-by: syzbot+4349872271ece473a7c91190b68b4bac7c5dbc87@syzkaller.appspotmail.com
Reported-by: syzbot+40bd32c4d9a3cc12a339@syzkaller.appspotmail.com
Reported-by: syzbot+769c54e66f994b041be7@syzkaller.appspotmail.com
Reported-by: syzbot+0a89a9ce473936c57065@syzkaller.appspotmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
drivers/block/loop.c