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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 155C2C43381 for ; Fri, 8 Mar 2019 07:27:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D589A20684 for ; Fri, 8 Mar 2019 07:27:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726427AbfCHHYl (ORCPT ); Fri, 8 Mar 2019 02:24:41 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:4655 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726275AbfCHHYl (ORCPT ); Fri, 8 Mar 2019 02:24:41 -0500 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 00621220D048E47D63C5; Fri, 8 Mar 2019 15:24:38 +0800 (CST) Received: from localhost.localdomain.localdomain (10.175.113.25) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.408.0; Fri, 8 Mar 2019 15:24:28 +0800 From: Kefeng Wang To: Bart Van Assche , Ingo Molnar , Tejun Heo , CC: Kefeng Wang , Subject: [PATCH] workqueue: unregister wq lockdep on error path in alloc_workqueue() Date: Fri, 8 Mar 2019 15:37:13 +0800 Message-ID: <20190308073713.39853-1-wangkefeng.wang@huawei.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.113.25] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org syzkaller report an issue "KASAN: use-after-free Read in alloc_workqueue", alloc_workqueue - kzalloc wq - wq_init_lockdep(wq); - lockdep_register_key(&wq->key); // add to hlist - kfree wq But forget to call wq_unregister_lockdep()->lockdep_unregister_key(), it will delete the entry from hlist. Reported-by: syzbot+17335689e239ce135d8b@syzkaller.appspotmail.com Fixes: 669de8bda87b ("kernel/workqueue: Use dynamic lockdep keys for workqueues") Signed-off-by: Kefeng Wang --- kernel/workqueue.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 7abbeed13421..9209d25dfade 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -4291,6 +4291,7 @@ struct workqueue_struct *alloc_workqueue(const char *fmt, return wq; err_free_wq: + wq_unregister_lockdep(wq); free_workqueue_attrs(wq->unbound_attrs); kfree(wq); return NULL; -- 2.20.1