From patchwork Sat Apr 1 06:40:09 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 9657561 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id F1DDF6035D for ; Sat, 1 Apr 2017 06:41:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E66DF286A1 for ; Sat, 1 Apr 2017 06:41:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DB5C2286CF; Sat, 1 Apr 2017 06:41:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 286BF286A2 for ; Sat, 1 Apr 2017 06:41:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751469AbdDAGlR (ORCPT ); Sat, 1 Apr 2017 02:41:17 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:34308 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750879AbdDAGlQ (ORCPT ); Sat, 1 Apr 2017 02:41:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=OLEf+vOUXw/jkhalg2W7tuff4ySv1zkDfLh9K8Lnntk=; b=iO9+HM7BVN5Livb6s3C6358/g qhFE54jwje5hH/Q5hQ/4xltZUydA7IWvJW9gryEe69sUQoQ4I6kCbkTDQeeoutRicFU1uYBxPjLRC eFi8w9dWZ6/L6lUJouLk18rlCgyfasdfIGKp4ljDsSYiSNCCTquZJszMPYbEj+zD2CdG6hf/zZh1e mQY7sGxWaiDbQcwjL5NBjVoNwvaLBymfBDmi0Oa/1EyrFoGZMHH7Ro5BEhRL0UVAVeEv/d8IausHh a0y8gU7rhEvvJzc8qP1hfgwBeMS83heuRQa91t7LFxvTy6PlIJM17iOWTPl4Ryq48Ed4D6D9FCEsL S7+kKZwzA==; Received: from 77.117.150.49.wireless.dyn.drei.com ([77.117.150.49] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.87 #1 (Red Hat Linux)) id 1cuCip-0002PS-80; Sat, 01 Apr 2017 06:41:15 +0000 From: Christoph Hellwig To: stable@vger.kernel.org Cc: linux-xfs@vger.kernel.org, "Darrick J. Wong" Subject: [PATCH 10/27] xfs: verify free block header fields Date: Sat, 1 Apr 2017 08:40:09 +0200 Message-Id: <20170401064026.5783-11-hch@lst.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170401064026.5783-1-hch@lst.de> References: <20170401064026.5783-1-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: "Darrick J. Wong" commit de14c5f541e78c59006bee56f6c5c2ef1ca07272 upstream. Perform basic sanity checking of the directory free block header fields so that we avoid hanging the system on invalid data. (Granted that just means that now we shutdown on directory write, but that seems better than hanging...) Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig --- fs/xfs/libxfs/xfs_dir2_node.c | 51 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 49 insertions(+), 2 deletions(-) diff --git a/fs/xfs/libxfs/xfs_dir2_node.c b/fs/xfs/libxfs/xfs_dir2_node.c index 75a557432d0f..bbd1238852b3 100644 --- a/fs/xfs/libxfs/xfs_dir2_node.c +++ b/fs/xfs/libxfs/xfs_dir2_node.c @@ -155,6 +155,42 @@ const struct xfs_buf_ops xfs_dir3_free_buf_ops = { .verify_write = xfs_dir3_free_write_verify, }; +/* Everything ok in the free block header? */ +static bool +xfs_dir3_free_header_check( + struct xfs_inode *dp, + xfs_dablk_t fbno, + struct xfs_buf *bp) +{ + struct xfs_mount *mp = dp->i_mount; + unsigned int firstdb; + int maxbests; + + maxbests = dp->d_ops->free_max_bests(mp->m_dir_geo); + firstdb = (xfs_dir2_da_to_db(mp->m_dir_geo, fbno) - + xfs_dir2_byte_to_db(mp->m_dir_geo, XFS_DIR2_FREE_OFFSET)) * + maxbests; + if (xfs_sb_version_hascrc(&mp->m_sb)) { + struct xfs_dir3_free_hdr *hdr3 = bp->b_addr; + + if (be32_to_cpu(hdr3->firstdb) != firstdb) + return false; + if (be32_to_cpu(hdr3->nvalid) > maxbests) + return false; + if (be32_to_cpu(hdr3->nvalid) < be32_to_cpu(hdr3->nused)) + return false; + } else { + struct xfs_dir2_free_hdr *hdr = bp->b_addr; + + if (be32_to_cpu(hdr->firstdb) != firstdb) + return false; + if (be32_to_cpu(hdr->nvalid) > maxbests) + return false; + if (be32_to_cpu(hdr->nvalid) < be32_to_cpu(hdr->nused)) + return false; + } + return true; +} static int __xfs_dir3_free_read( @@ -168,11 +204,22 @@ __xfs_dir3_free_read( err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp, XFS_DATA_FORK, &xfs_dir3_free_buf_ops); + if (err || !*bpp) + return err; + + /* Check things that we can't do in the verifier. */ + if (!xfs_dir3_free_header_check(dp, fbno, *bpp)) { + xfs_buf_ioerror(*bpp, -EFSCORRUPTED); + xfs_verifier_error(*bpp); + xfs_trans_brelse(tp, *bpp); + return -EFSCORRUPTED; + } /* try read returns without an error or *bpp if it lands in a hole */ - if (!err && tp && *bpp) + if (tp) xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_FREE_BUF); - return err; + + return 0; } int