Commit c093ee4f authored Nov 05, 2010 by Linus Torvalds

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



Commit 48821184 ("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>

parent 433039e9

drivers/block/floppy.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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;
		}

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