From patchwork Tue Sep 29 10:59:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 263330 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=-13.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, 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 6E7ABC4727F for ; Tue, 29 Sep 2020 11:16:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 28D4A20848 for ; Tue, 29 Sep 2020 11:16:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601378166; bh=G2pROOOvv0dU3i/XznMnDTbgZaexADnv4FKP0yQoJY8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=HyKx5iLzDNibqpJcf5FuleMmr3tCoxHiHxGXE9GZGn06sa1WcKsykEjKekJO7sLGX lEwaaBxSNT2aghiblUH8RSJxdUTs5L9R4JIiWsig0c4a0YR4FKpqBIcfZeMaGhQ15i XozKf2FIG78eCt/eixHNckv4PecJ6kfe4KrI76ec= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729556AbgI2LQE (ORCPT ); Tue, 29 Sep 2020 07:16:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:60662 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729551AbgI2LQB (ORCPT ); Tue, 29 Sep 2020 07:16:01 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0A75C21D41; Tue, 29 Sep 2020 11:15:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601378160; bh=G2pROOOvv0dU3i/XznMnDTbgZaexADnv4FKP0yQoJY8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EV/W3tA7yFidhb268XibEDhwWorqSHfLJYwonn43w3gLaz8Lq9CwcWinfmodUcN/x 0/qnNg5CxR3/c7Zi1UUblZxnbcsGBMz4tm+mGId+KOMwN9HLf4GFMym/ZkcaYSxUdR 8I6bhKFzDoKpLBKAeB301LZVDq1Zw3B2RyieoXRg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Darrick J. Wong" , Dave Chinner , Sasha Levin Subject: [PATCH 4.14 082/166] xfs: dont ever return a stale pointer from __xfs_dir3_free_read Date: Tue, 29 Sep 2020 12:59:54 +0200 Message-Id: <20200929105939.308636246@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929105935.184737111@linuxfoundation.org> References: <20200929105935.184737111@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 682e2bf370c72..ee4ebc2dd7492 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; }