From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f172.google.com ([209.85.220.172]:35331 "EHLO mail-qk0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751505AbbICUsv (ORCPT ); Thu, 3 Sep 2015 16:48:51 -0400 Received: by qkcj187 with SMTP id j187so777059qkc.2 for ; Thu, 03 Sep 2015 13:48:51 -0700 (PDT) Received: from foobar.home (pool-71-163-182-126.washdc.fios.verizon.net. [71.163.182.126]) by smtp.googlemail.com with ESMTPSA id 95sm32190qgt.12.2015.09.03.13.48.50 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 03 Sep 2015 13:48:50 -0700 (PDT) Message-ID: <1441313329.2546.38.camel@gmail.com> Subject: [PATCH 3.14] udf: Check length of extended attributes and allocation descriptors From: "Charles (Chas) Williams" <3chas3@gmail.com> To: stable@vger.kernel.org Date: Thu, 03 Sep 2015 16:48:49 -0400 Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: stable-owner@vger.kernel.org List-ID: From: Jan Kara commit 23b133bdc452aa441fcb9b82cbf6dd05cfd342d0 upstream. Check length of extended attributes and allocation descriptors when loading inodes from disk. Otherwise corrupted filesystems could confuse the code and make the kernel oops. This fixes CVE-2015-4167. Reported-by: Carl Henrik Lunde Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman [Use make_bad_inode() instead of branching due to older implementation.] Signed-off-by: Chas Williams <3chas3@gmail.com> --- fs/udf/inode.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/fs/udf/inode.c b/fs/udf/inode.c index 287cd5f..142d29e 100644 --- a/fs/udf/inode.c +++ b/fs/udf/inode.c @@ -1496,6 +1496,22 @@ static void udf_fill_inode(struct inode *inode, struct buffer_head *bh) iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint); } + /* + * Sanity check length of allocation descriptors and extended attrs to + * avoid integer overflows + */ + if (iinfo->i_lenEAttr > inode->i_sb->s_blocksize + || iinfo->i_lenAlloc > inode->i_sb->s_blocksize) { + make_bad_inode(inode); + return; + } + /* Now do exact checks */ + if (udf_file_entry_alloc_offset(inode) + + iinfo->i_lenAlloc > inode->i_sb->s_blocksize) { + make_bad_inode(inode); + return; + } + switch (fe->icbTag.fileType) { case ICBTAG_FILE_TYPE_DIRECTORY: inode->i_op = &udf_dir_inode_operations; -- 2.1.0