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=-10.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 6E15FC04EBF for ; Wed, 5 Dec 2018 09:51:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3490B2082B for ; Wed, 5 Dec 2018 09:51:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="c8w8WbGa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3490B2082B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729867AbeLEJvd (ORCPT ); Wed, 5 Dec 2018 04:51:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:57836 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728312AbeLEJvb (ORCPT ); Wed, 5 Dec 2018 04:51:31 -0500 Received: from sasha-vm.mshome.net (unknown [213.57.143.11]) (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 BCA952133F; Wed, 5 Dec 2018 09:51:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544003490; bh=nr07QfpQxKNUTyE4M0hVOK/9waEDv4CVMWlOJ5aPZpA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c8w8WbGa/5u/TWvG02M14mK6CSBD5L9SI2TofYO0fAAX738dtg1rWA2OegqE24f9o Q4g1pPqMh26P/HKGV4D0hPiBuhAMVPDzx8/WWHdNuaJcIc7L0LBA4MAFxtMtcDzVg6 cSoMOBk6bda4/kqTmBuW2dywAQlyAUzyQesfEHqE= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Pan Bian , Mark Fasheh , Joel Becker , Junxiao Bi , Joseph Qi , Changwei Ge , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH AUTOSEL 4.9 45/45] ocfs2: fix potential use after free Date: Wed, 5 Dec 2018 04:47:06 -0500 Message-Id: <20181205094706.7225-45-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181205094706.7225-1-sashal@kernel.org> References: <20181205094706.7225-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pan Bian [ Upstream commit 164f7e586739d07eb56af6f6d66acebb11f315c8 ] ocfs2_get_dentry() calls iput(inode) to drop the reference count of inode, and if the reference count hits 0, inode is freed. However, in this function, it then reads inode->i_generation, which may result in a use after free bug. Move the put operation later. Link: http://lkml.kernel.org/r/1543109237-110227-1-git-send-email-bianpan2016@163.com Fixes: 781f200cb7a("ocfs2: Remove masklog ML_EXPORT.") Signed-off-by: Pan Bian 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/export.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ocfs2/export.c b/fs/ocfs2/export.c index 827fc9809bc2..3494e220b510 100644 --- a/fs/ocfs2/export.c +++ b/fs/ocfs2/export.c @@ -125,10 +125,10 @@ static struct dentry *ocfs2_get_dentry(struct super_block *sb, check_gen: if (handle->ih_generation != inode->i_generation) { - iput(inode); trace_ocfs2_get_dentry_generation((unsigned long long)blkno, handle->ih_generation, inode->i_generation); + iput(inode); result = ERR_PTR(-ESTALE); goto bail; } -- 2.17.1