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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 ACF8AC432C3 for ; Sat, 16 Nov 2019 15:52:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 866BC20859 for ; Sat, 16 Nov 2019 15:52:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573919537; bh=+FbwtVexOLimGFpjt3lzrQHpz3nlo14QU2WhTo5OPfY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IMY0B54aBMmzNho0Ot+ZfcF0IjEPPh919UwLRckrIpASf+bIQ2gMBe7fPz/Ukv+ls /sgLZJre2T7p4witCpy1e2xMts9KNqPDiczg52FTGNikroqcf2d+oS7oj9dx85TZCT cSagO726CSKFLmUaI/mFOz735ECsKKTf4Dw/DKzk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731004AbfKPPwQ (ORCPT ); Sat, 16 Nov 2019 10:52:16 -0500 Received: from mail.kernel.org ([198.145.29.99]:32940 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730158AbfKPPwO (ORCPT ); Sat, 16 Nov 2019 10:52:14 -0500 Received: from sasha-vm.mshome.net (unknown [50.234.116.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 360F420728; Sat, 16 Nov 2019 15:52:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573919533; bh=+FbwtVexOLimGFpjt3lzrQHpz3nlo14QU2WhTo5OPfY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nSRSNyN/fwW58vY1NFSH2zfqL9GNvL6SoV5bF41oDd7O25srguJaQ/YEQb9E18VYJ Qo+W2cvZ0vA+qZW5j//8WxzdlS0Ep+RQQd40aHUjrYLkA7FWacWlrfsyWrsA8mUT5G nPE5N8jc6GvFeL3zXixL9tUK1awjmZ6uTJTBrnyg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jia-Ju Bai , Andrew Morton , Mark Fasheh , Joel Becker , Junxiao Bi , Joseph Qi , Changwei Ge , Linus Torvalds , Sasha Levin Subject: [PATCH AUTOSEL 4.9 52/99] fs/ocfs2/dlm/dlmdebug.c: fix a sleep-in-atomic-context bug in dlm_print_one_mle() Date: Sat, 16 Nov 2019 10:50:15 -0500 Message-Id: <20191116155103.10971-52-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191116155103.10971-1-sashal@kernel.org> References: <20191116155103.10971-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jia-Ju Bai [ Upstream commit 999865764f5f128896402572b439269acb471022 ] The kernel module may sleep with holding a spinlock. The function call paths (from bottom to top) in Linux-4.16 are: [FUNC] get_zeroed_page(GFP_NOFS) fs/ocfs2/dlm/dlmdebug.c, 332: get_zeroed_page in dlm_print_one_mle fs/ocfs2/dlm/dlmmaster.c, 240: dlm_print_one_mle in __dlm_put_mle fs/ocfs2/dlm/dlmmaster.c, 255: __dlm_put_mle in dlm_put_mle fs/ocfs2/dlm/dlmmaster.c, 254: spin_lock in dlm_put_ml [FUNC] get_zeroed_page(GFP_NOFS) fs/ocfs2/dlm/dlmdebug.c, 332: get_zeroed_page in dlm_print_one_mle fs/ocfs2/dlm/dlmmaster.c, 240: dlm_print_one_mle in __dlm_put_mle fs/ocfs2/dlm/dlmmaster.c, 222: __dlm_put_mle in dlm_put_mle_inuse fs/ocfs2/dlm/dlmmaster.c, 219: spin_lock in dlm_put_mle_inuse To fix this bug, GFP_NOFS is replaced with GFP_ATOMIC. This bug is found by my static analysis tool DSAC. Link: http://lkml.kernel.org/r/20180901112528.27025-1-baijiaju1990@gmail.com Signed-off-by: Jia-Ju Bai Reviewed-by: Andrew Morton Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Joseph Qi Cc: Changwei Ge Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- fs/ocfs2/dlm/dlmdebug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c index e7b760deefaee..32d60f69db24c 100644 --- a/fs/ocfs2/dlm/dlmdebug.c +++ b/fs/ocfs2/dlm/dlmdebug.c @@ -329,7 +329,7 @@ void dlm_print_one_mle(struct dlm_master_list_entry *mle) { char *buf; - buf = (char *) get_zeroed_page(GFP_NOFS); + buf = (char *) get_zeroed_page(GFP_ATOMIC); if (buf) { dump_mle(mle, buf, PAGE_SIZE - 1); free_page((unsigned long)buf); -- 2.20.1