From patchwork Mon Jun 5 08:05:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia-Ju Bai X-Patchwork-Id: 9765693 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id E361960364 for ; Mon, 5 Jun 2017 08:02:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D33D827D4A for ; Mon, 5 Jun 2017 08:02:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C5F5827E71; Mon, 5 Jun 2017 08:02:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, FREEMAIL_FROM,RCVD_IN_DNSWL_HI,RCVD_IN_SORBS_SPAM,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6807227D4A for ; Mon, 5 Jun 2017 08:02:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751361AbdFEICw (ORCPT ); Mon, 5 Jun 2017 04:02:52 -0400 Received: from m12-13.163.com ([220.181.12.13]:56368 "EHLO m12-13.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751336AbdFEICv (ORCPT ); Mon, 5 Jun 2017 04:02:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=GOhy47vUNIANoXKZvF BGywrKee5YzymqjooIxusAXcA=; b=bUnmsjmDlyPe3y5LJ8S1MUHScLRgCnDQNL W73b6xSzF4yf1NiGazyjGCpbJtU+wKK2x1rm7ki49UEDjFe+5nvClVo75hmswEhe 36ETDHxoheXaQriNuy39b4ziJx16zdG2SWNOxSn+VxCESmIjwV7OSCyNTJpd2yNq LJ3ubcCyg= Received: from bai-oslab.tsinghua.edu.cn (unknown [166.111.70.19]) by smtp9 (Coremail) with SMTP id DcCowABnbjocEDVZKhtZIQ--.27764S2; Mon, 05 Jun 2017 16:02:39 +0800 (CST) From: Jia-Ju Bai To: trond.myklebust@primarydata.com, anna.schumaker@netapp.com Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] fs: nfs: Fix a sleep-in-atomic bug in nfs_access_add_cache Date: Mon, 5 Jun 2017 16:05:04 +0800 Message-Id: <1496649904-1855-1-git-send-email-baijiaju1990@163.com> X-Mailer: git-send-email 1.7.9.5 X-CM-TRANSID: DcCowABnbjocEDVZKhtZIQ--.27764S2 X-Coremail-Antispam: 1Uf129KBjvdXoW7XFy3WFWktF43CFWUJF1xAFb_yoWfZFX_uF 4xJrWxuay3Wr4SvrsxKF4SkFZYvF48AFyFvFs3KF13ta45JFZ7ArnFyr43XasxGrWIkasx Cwn8Gr1DKr13WjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IUjPxhtUUUUU== X-Originating-IP: [166.111.70.19] X-CM-SenderInfo: xedlyx5dmximizq6il2tof0z/1tbiGB-telXlZ4wiVAAAs9 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The driver may sleep under a rcu read lock, and function call path is: nfs_permission (acquire the lock by rcu_read_lock) nfs_do_access nfs_access_add_cache kmalloc(GFP_KERNEL) --> may sleep To fix it, "GFP_KERNEL" is replaced with "GFP_ATOMIC". Signed-off-by: Jia-Ju Bai --- fs/nfs/dir.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 32ccd77..7a074db 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -2333,7 +2333,7 @@ static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry * void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set) { - struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL); + struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_ATOMIC); if (cache == NULL) return; RB_CLEAR_NODE(&cache->rb_node);