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=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 5403AC43464 for ; Fri, 18 Sep 2020 02:26:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 15F3B235F7 for ; Fri, 18 Sep 2020 02:26:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600396003; bh=HoEJHSuSC3WoC4fJuv/cSWXVqx51YbdqwK1THED12wg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=wOBcW6+FuUnnhvP0lcCt2F9XrdTbLg5RN27g2WSSR0LeqhCtCTg0FlGC8P5jMi8iH iNgi7JygLiKkrSOQ3lCzTAQCrxejsxUa8zO1FvEdZTqp5DEWZOz0K0WeUmag2OoBnM XkHIj9ek7oOQL+ZMI9kGljEsw+b5beOqBSQzcdnQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729655AbgIRC0m (ORCPT ); Thu, 17 Sep 2020 22:26:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:45048 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729317AbgIRCQA (ORCPT ); Thu, 17 Sep 2020 22:16:00 -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 3A07A23977; Fri, 18 Sep 2020 02:15:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600395355; bh=HoEJHSuSC3WoC4fJuv/cSWXVqx51YbdqwK1THED12wg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l9/RXmJ3l6pRsxoJqPH4kf9kUjjurUqLizLCnYUAC3MfrwvSg64TPq9JH2rO8hs2+ sG0jenHGv4PTA8JBvcZg/qz6vVD2i1ATvpNo+cRt6wAaFGx7WDqRPNWUe07GetQtme 2AwBeCeRzjXehh6zSasAAXoNrBR14RhhNUdG0VpQ= 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 4.9 50/90] xfs: don't ever return a stale pointer from __xfs_dir3_free_read Date: Thu, 17 Sep 2020 22:14:15 -0400 Message-Id: <20200918021455.2067301-50-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200918021455.2067301-1-sashal@kernel.org> References: <20200918021455.2067301-1-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 bbd1238852b3c..df7f33e60a4f6 100644 --- a/fs/xfs/libxfs/xfs_dir2_node.c +++ b/fs/xfs/libxfs/xfs_dir2_node.c @@ -212,6 +212,7 @@ __xfs_dir3_free_read( xfs_buf_ioerror(*bpp, -EFSCORRUPTED); xfs_verifier_error(*bpp); xfs_trans_brelse(tp, *bpp); + *bpp = NULL; return -EFSCORRUPTED; } -- 2.25.1