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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 9C6DAC43465 for ; Fri, 18 Sep 2020 02:45:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E49523444 for ; Fri, 18 Sep 2020 02:45:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600397137; bh=kwcM2qwxJgCv57MH0K50BLRPXoO0gKATYQzb09+nIgc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zXomX5YCLmUp3Hya9WPcV3/ustEbWoCnL0ad17IJj7gSJCWmvVaT9LzMCS1EWDF5i mTx64msMOfJLWOAhJcpBBwZUWM/NotIRKmktGSTb9feNyQPk0Y73t9M60EEuOK6mcs nxPQZASO3TF+HOLtIQgZGFLOFtLWIkme9PO/rP4Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730232AbgIRCpd (ORCPT ); Thu, 17 Sep 2020 22:45:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:34748 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728425AbgIRCKS (ORCPT ); Thu, 17 Sep 2020 22:10:18 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 799F62395A; Fri, 18 Sep 2020 02:10:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600395011; bh=kwcM2qwxJgCv57MH0K50BLRPXoO0gKATYQzb09+nIgc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zxApaJ/OJBxHw0s2xN01WI2E/eUSax7ReHigMIopX3XJU4ahvhvfZi5CSm/cSVFJT idUXnRz881jXlKb6prUQqy0nbQSVN9m7lMwckkWrecKAQkt+IZcYQT+eiYgqAR9vHR 6i7pvV268vyN0W249QVnKKfPzuj5dbCNNE/KPSt4= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Darrick J. Wong" , Dave Chinner , Sasha Levin , xfs@oss.sgi.com Subject: [PATCH AUTOSEL 4.19 106/206] xfs: don't ever return a stale pointer from __xfs_dir3_free_read Date: Thu, 17 Sep 2020 22:06:22 -0400 Message-Id: <20200918020802.2065198-106-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200918020802.2065198-1-sashal@kernel.org> References: <20200918020802.2065198-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Darrick J. Wong" [ Upstream commit 1cb5deb5bc095c070c09a4540c45f9c9ba24be43 ] If we decide that a directory free block is corrupt, we must take care not to leak a buffer pointer to the caller. After xfs_trans_brelse returns, the buffer can be freed or reused, which means that we have to set *bpp back to NULL. Callers are supposed to notice the nonzero return value and not use the buffer pointer, but we should code more defensively, even if all current callers handle this situation correctly. Fixes: de14c5f541e7 ("xfs: verify free block header fields") Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner Signed-off-by: Sasha Levin --- fs/xfs/libxfs/xfs_dir2_node.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/xfs/libxfs/xfs_dir2_node.c b/fs/xfs/libxfs/xfs_dir2_node.c index f1bb3434f51c7..01e99806b941f 100644 --- a/fs/xfs/libxfs/xfs_dir2_node.c +++ b/fs/xfs/libxfs/xfs_dir2_node.c @@ -214,6 +214,7 @@ __xfs_dir3_free_read( if (fa) { xfs_verifier_error(*bpp, -EFSCORRUPTED, fa); xfs_trans_brelse(tp, *bpp); + *bpp = NULL; return -EFSCORRUPTED; } -- 2.25.1