From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83BE8C43381 for ; Sat, 9 Mar 2019 14:43:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5A4D32081B for ; Sat, 9 Mar 2019 14:43:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726596AbfCIOnX (ORCPT ); Sat, 9 Mar 2019 09:43:23 -0500 Received: from terminus.zytor.com ([198.137.202.136]:53875 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725841AbfCIOnX (ORCPT ); Sat, 9 Mar 2019 09:43:23 -0500 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id x29Eh3E23109912 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Sat, 9 Mar 2019 06:43:03 -0800 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id x29Eh29H3109909; Sat, 9 Mar 2019 06:43:02 -0800 Date: Sat, 9 Mar 2019 06:43:02 -0800 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Qian Cai Message-ID: Cc: dave.hansen@linux.intel.com, bp@alien8.de, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, tglx@linutronix.de, torvalds@linux-foundation.org, bvanassche@acm.org, peterz@infradead.org, riel@surriel.com, luto@kernel.org, cai@lca.pw, mingo@kernel.org, hpa@zytor.com, will.deacon@arm.com, paulmck@linux.vnet.ibm.com Reply-To: torvalds@linux-foundation.org, peterz@infradead.org, bvanassche@acm.org, linux-kernel@vger.kernel.org, bp@alien8.de, dave.hansen@linux.intel.com, tglx@linutronix.de, akpm@linux-foundation.org, will.deacon@arm.com, paulmck@linux.vnet.ibm.com, riel@surriel.com, mingo@kernel.org, luto@kernel.org, cai@lca.pw, hpa@zytor.com In-Reply-To: <20190307002731.47371-1-cai@lca.pw> References: <20190307002731.47371-1-cai@lca.pw> To: linux-tip-commits@vger.kernel.org Subject: [tip:locking/urgent] workqueue, lockdep: Fix a memory leak in wq->lock_name Git-Commit-ID: 69a106c00e8554a7e6b3f4bb2967332670f89337 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 69a106c00e8554a7e6b3f4bb2967332670f89337 Gitweb: https://git.kernel.org/tip/69a106c00e8554a7e6b3f4bb2967332670f89337 Author: Qian Cai AuthorDate: Wed, 6 Mar 2019 19:27:31 -0500 Committer: Ingo Molnar CommitDate: Sat, 9 Mar 2019 14:15:52 +0100 workqueue, lockdep: Fix a memory leak in wq->lock_name The following commit: 669de8bda87b ("kernel/workqueue: Use dynamic lockdep keys for workqueues") introduced a memory leak as wq_free_lockdep() calls kfree(wq->lock_name), but wq_init_lockdep() does not point wq->lock_name to the newly allocated slab object. This can be reproduced by running LTP fallocate04 followed by oom01 tests: unreferenced object 0xc0000005876384d8 (size 64): comm "fallocate04", pid 26972, jiffies 4297139141 (age 40370.480s) hex dump (first 32 bytes): 28 77 71 5f 63 6f 6d 70 6c 65 74 69 6f 6e 29 65 (wq_completion)e 78 74 34 2d 72 73 76 2d 63 6f 6e 76 65 72 73 69 xt4-rsv-conversi backtrace: [<00000000cb452883>] kvasprintf+0x6c/0xe0 [<000000004654ddac>] kasprintf+0x34/0x60 [<000000001c68f311>] alloc_workqueue+0x1f8/0x6ac [<0000000003c2ad83>] ext4_fill_super+0x23d4/0x3c80 [ext4] [<0000000006610538>] mount_bdev+0x25c/0x290 [<00000000bcf955ec>] ext4_mount+0x28/0x50 [ext4] [<0000000016e08fd3>] legacy_get_tree+0x4c/0xb0 [<0000000042b6a5fc>] vfs_get_tree+0x6c/0x190 [<00000000268ab022>] do_mount+0xb9c/0x1100 [<00000000698e6898>] ksys_mount+0x158/0x180 [<0000000064e391fd>] sys_mount+0x20/0x30 [<00000000ba378f12>] system_call+0x5c/0x70 Signed-off-by: Qian Cai Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Bart Van Assche Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: Will Deacon Cc: catalin.marinas@arm.com Cc: jiangshanlai@gmail.com Cc: tj@kernel.org Fixes: 669de8bda87b ("kernel/workqueue: Use dynamic lockdep keys for workqueues") Link: https://lkml.kernel.org/r/20190307002731.47371-1-cai@lca.pw Signed-off-by: Ingo Molnar --- kernel/workqueue.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index ecdd5e6f2166..e14da4f599ab 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -3348,6 +3348,8 @@ static void wq_init_lockdep(struct workqueue_struct *wq) lock_name = kasprintf(GFP_KERNEL, "%s%s", "(wq_completion)", wq->name); if (!lock_name) lock_name = wq->name; + + wq->lock_name = lock_name; lockdep_init_map(&wq->lockdep_map, lock_name, &wq->key, 0); }