floppy: fix use-after-free in module load failure path

Commit 488211844e ("floppy: switch to one queue per drive instead of
sharing a queue") introduced a use-after-free.  We do "put_disk()" on
the disk device _before_ we then clean up the queue associated with that
disk.

Move the put_disk() down to avoid dereferencing a free'd data structure.

Cc: Jens Axboe <jaxboe@fusionio.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Reported-and-tested-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds 2010-11-05 17:45:59 -07:00
parent 433039e97f
commit c093ee4f07

View File

@ -4363,9 +4363,9 @@ out_unreg_blkdev:
out_put_disk:
while (dr--) {
del_timer(&motor_off_timer[dr]);
put_disk(disks[dr]);
if (disks[dr]->queue)
blk_cleanup_queue(disks[dr]->queue);
put_disk(disks[dr]);
}
return err;
}