Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753474Ab2BVPq5 (ORCPT ); Wed, 22 Feb 2012 10:46:57 -0500 Received: from sh.osrg.net ([192.16.179.4]:59560 "EHLO sh.osrg.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752023Ab2BVPqy (ORCPT ); Wed, 22 Feb 2012 10:46:54 -0500 Date: Thu, 23 Feb 2012 00:46:50 +0900 (JST) Message-Id: <20120223.004650.160012804.ryusuke@osrg.net> To: haogangchen@gmail.com Cc: linux-nilfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] FS: nilfs2: clamps ns_r_segments_percentage to [1, 99] From: Ryusuke Konishi In-Reply-To: <1329774930-17162-1-git-send-email-haogangchen@gmail.com> References: <1329774930-17162-1-git-send-email-haogangchen@gmail.com> X-Mailer: Mew version 5.2 on Emacs 22.2 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.3.7 (sh.osrg.net [192.16.179.4]); Thu, 23 Feb 2012 00:46:50 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1884 Lines: 54 Hi, Chen On Mon, 20 Feb 2012 16:55:30 -0500, Haogang Chen wrote: > ns_r_segments_percentage is read from the disk. Bogus or malicious > value could cause integer overflow and potential security holes. > This patch reports error when mounting such bogus volumes. > > Signed-off-by: Haogang Chen Ok, I will pick this up as a fix. But this seems not to cause security issues; it just makes some disk usage calculations meaningless and causes malfunction for such out-of-range values. Right? May I amend the change log in terms of the impact ? Thanks, Ryusuke Konishi > --- > fs/nilfs2/the_nilfs.c | 6 ++++++ > 1 files changed, 6 insertions(+), 0 deletions(-) > > diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c > index d327140..e12b47b 100644 > --- a/fs/nilfs2/the_nilfs.c > +++ b/fs/nilfs2/the_nilfs.c > @@ -409,6 +409,12 @@ static int nilfs_store_disk_layout(struct the_nilfs *nilfs, > nilfs->ns_first_data_block = le64_to_cpu(sbp->s_first_data_block); > nilfs->ns_r_segments_percentage = > le32_to_cpu(sbp->s_r_segments_percentage); > + if (nilfs->ns_r_segments_percentage < 1 || > + nilfs->ns_r_segments_percentage > 99) { > + printk(KERN_ERR "NILFS: invalid reserved segments percentage.\n"); > + return -EINVAL; > + } > + > nilfs_set_nsegments(nilfs, le64_to_cpu(sbp->s_nsegments)); > nilfs->ns_crc_seed = le32_to_cpu(sbp->s_crc_seed); > return 0; > -- > 1.7.5.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/