From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751866AbdBJWHA (ORCPT ); Fri, 10 Feb 2017 17:07:00 -0500 Received: from mail.kernel.org ([198.145.29.136]:56398 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751644AbdBJWG6 (ORCPT ); Fri, 10 Feb 2017 17:06:58 -0500 From: "Luis R. Rodriguez" To: jeyu@redhat.com, rusty@rustcorp.com.au Cc: mbenes@suse.cz, atomlin@redhat.com, pmladek@suse.com, hare@suse.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, "Luis R. Rodriguez" , "stable # v2 . 6 . 30" Subject: [PATCH] module: fix memory leak on early load_module() failures Date: Fri, 10 Feb 2017 14:06:22 -0800 Message-Id: <20170210220622.5220-1-mcgrof@kernel.org> X-Mailer: git-send-email 2.11.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org While looking for early possible module loading failures I was able to reproduce a memory leak possible with kmemleak. There are a few rare ways to trigger a failure: o we've run into a failure while processing kernel parameters (parse_args() returns an error) o mod_sysfs_setup() fails o we're a live patch module and copy_module_elf() fails Chances of running into this issue is really low. kmemleak splat: unreferenced object 0xffff9f2c4ada1b00 (size 32): comm "kworker/u16:4", pid 82, jiffies 4294897636 (age 681.816s) hex dump (first 32 bytes): 6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0....... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmemleak_alloc+0x4a/0xa0 [] __kmalloc_track_caller+0x126/0x230 [] kstrdup+0x31/0x60 [] kstrdup_const+0x24/0x30 [] kvasprintf_const+0x7a/0x90 [] kobject_set_name_vargs+0x21/0x90 [] dev_set_name+0x47/0x50 [] memstick_check+0x95/0x33c [memstick] [] process_one_work+0x1f3/0x4b0 [] worker_thread+0x48/0x4e0 [] kthread+0xc9/0xe0 [] ret_from_fork+0x1f/0x40 [] 0xffffffffffffffff Cc: stable # v2.6.30 Fixes: e180a6b7759a ("param: fix charp parameters set via sysfs") Reviewed-by: Miroslav Benes Reviewed-by: Aaron Tomlin Signed-off-by: Luis R. Rodriguez --- kernel/module.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/module.c b/kernel/module.c index 38d4270925d4..8409a82424d2 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3722,6 +3722,7 @@ static int load_module(struct load_info *info, const char __user *uargs, mod_sysfs_teardown(mod); coming_cleanup: mod->state = MODULE_STATE_GOING; + destroy_params(mod->kp, mod->num_kp); blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_GOING, mod); klp_module_going(mod); -- 2.10.2