From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162616Ab2GLXTa (ORCPT ); Thu, 12 Jul 2012 19:19:30 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:47532 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1162564Ab2GLXDq (ORCPT ); Thu, 12 Jul 2012 19:03:46 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg KH , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jan Kara Subject: [ 19/68] udf: Avoid run away loop when partition table length is corrupted Date: Thu, 12 Jul 2012 16:01:53 -0700 Message-Id: <20120712175037.120653526@linuxfoundation.org> X-Mailer: git-send-email 1.7.10.1.362.g242cab3 In-Reply-To: <20120712175035.530652872@linuxfoundation.org> References: <20120712175057.GA9917@kroah.com> <20120712175035.530652872@linuxfoundation.org> User-Agent: quilt/0.60-20.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg KH 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kara commit adee11b2085bee90bd8f4f52123ffb07882d6256 upstream. Check provided length of partition table so that (possibly maliciously) corrupted partition table cannot cause accessing data beyond current buffer. Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman --- fs/udf/super.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/fs/udf/super.c +++ b/fs/udf/super.c @@ -1254,6 +1254,7 @@ static int udf_load_logicalvol(struct su struct genericPartitionMap *gpm; uint16_t ident; struct buffer_head *bh; + unsigned int table_len; int ret = 0; bh = udf_read_tagged(sb, block, block, &ident); @@ -1261,13 +1262,20 @@ static int udf_load_logicalvol(struct su return 1; BUG_ON(ident != TAG_IDENT_LVD); lvd = (struct logicalVolDesc *)bh->b_data; + table_len = le32_to_cpu(lvd->mapTableLength); + if (sizeof(*lvd) + table_len > sb->s_blocksize) { + udf_error(sb, __func__, "error loading logical volume descriptor: " + "Partition table too long (%u > %lu)\n", table_len, + sb->s_blocksize - sizeof(*lvd)); + goto out_bh; + } ret = udf_sb_alloc_partition_maps(sb, le32_to_cpu(lvd->numPartitionMaps)); if (ret) goto out_bh; for (i = 0, offset = 0; - i < sbi->s_partitions && offset < le32_to_cpu(lvd->mapTableLength); + i < sbi->s_partitions && offset < table_len; i++, offset += gpm->partitionMapLength) { struct udf_part_map *map = &sbi->s_partmaps[i]; gpm = (struct genericPartitionMap *)