Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752222Ab3CREqK (ORCPT ); Mon, 18 Mar 2013 00:46:10 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33481 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751721Ab3CREaX (ORCPT ); Mon, 18 Mar 2013 00:30:23 -0400 Message-Id: <20130318042152.013140222@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 18 Mar 2013 04:23:04 +0000 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: akpm@linux-foundation.org, Guo Chao , Alexander Viro , "M. Hindess" , Nikanth Karthikesan , Jens Axboe Subject: [ 80/82] loopdev: remove an user triggerable oops In-Reply-To: <20130318042144.234468645@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:d98f:da4e:f620:7bea X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2442 Lines: 87 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guo Chao commit b1a6650406875b9097a032eed89af50682fe1160 upstream. 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 Cc: Alexander Viro Cc: Guo Chao Cc: M. Hindess Cc: Nikanth Karthikesan Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe Signed-off-by: Ben Hutchings --- drivers/block/loop.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1834,11 +1834,15 @@ 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. @@ -1856,8 +1860,10 @@ 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); @@ -1870,6 +1876,10 @@ 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) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/