diff options
author | Guo Chao <yan@linux.vnet.ibm.com> | 2013-02-21 15:16:49 -0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2013-02-22 10:43:22 +0100 |
commit | b1a6650406875b9097a032eed89af50682fe1160 (patch) | |
tree | 2521139daec844942ca85e30c86c0218cc8f7a52 /drivers/block/loop.c | |
parent | 7b0576a3d835b4d46ed85d817ce016e90bf293a3 (diff) | |
download | linux-b1a6650406875b9097a032eed89af50682fe1160.tar.bz2 |
loopdev: remove an user triggerable oops
When loopdev is built as module and we pass an invalid parameter,
loop_init() will return directly without deregister misc device, which
will cause an oops when insert loop module next time because we left some
garbage in the misc device list.
Test case:
sudo modprobe loop max_part=1024
(failed due to invalid parameter)
sudo modprobe loop
(oops)
Clean up nicely to avoid such oops.
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: M. Hindess <hindessm@uk.ibm.com>
Cc: Nikanth Karthikesan <knikanth@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block/loop.c')
-rw-r--r-- | drivers/block/loop.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 6579f69fd7a4..1b1b0c981a85 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1844,11 +1844,15 @@ static int __init loop_init(void) max_part = (1UL << part_shift) - 1; } - if ((1UL << part_shift) > DISK_MAX_PARTS) - return -EINVAL; + if ((1UL << part_shift) > DISK_MAX_PARTS) { + err = -EINVAL; + goto misc_out; + } - if (max_loop > 1UL << (MINORBITS - part_shift)) - return -EINVAL; + if (max_loop > 1UL << (MINORBITS - part_shift)) { + err = -EINVAL; + goto misc_out; + } /* * If max_loop is specified, create that many devices upfront. @@ -1866,8 +1870,10 @@ static int __init loop_init(void) range = 1UL << MINORBITS; } - if (register_blkdev(LOOP_MAJOR, "loop")) - return -EIO; + if (register_blkdev(LOOP_MAJOR, "loop")) { + err = -EIO; + goto misc_out; + } blk_register_region(MKDEV(LOOP_MAJOR, 0), range, THIS_MODULE, loop_probe, NULL, NULL); @@ -1880,6 +1886,10 @@ static int __init loop_init(void) printk(KERN_INFO "loop: module loaded\n"); return 0; + +misc_out: + misc_deregister(&loop_misc); + return err; } static int loop_exit_cb(int id, void *ptr, void *data) |