From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752300Ab1H0Ozc (ORCPT ); Sat, 27 Aug 2011 10:55:32 -0400 Received: from cantor2.suse.de ([195.135.220.15]:46333 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751973Ab1H0Oza (ORCPT ); Sat, 27 Aug 2011 10:55:30 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Aug 26 15:01:20 2011 Message-Id: <20110826220120.726579794@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Fri, 26 Aug 2011 14:58:32 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Timo Warns Subject: [11/19] befs: Validate length of long symbolic links. In-Reply-To: <20110826220137.GA14059@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Timo Warns commit 338d0f0a6fbc82407864606f5b64b75aeb3c70f2 upstream. Signed-off-by: Timo Warns Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/befs/linuxvfs.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) --- a/fs/befs/linuxvfs.c +++ b/fs/befs/linuxvfs.c @@ -469,17 +469,22 @@ befs_follow_link(struct dentry *dentry, befs_data_stream *data = &befs_ino->i_data.ds; befs_off_t len = data->size; - befs_debug(sb, "Follow long symlink"); - - link = kmalloc(len, GFP_NOFS); - if (!link) { - link = ERR_PTR(-ENOMEM); - } else if (befs_read_lsymlink(sb, data, link, len) != len) { - kfree(link); - befs_error(sb, "Failed to read entire long symlink"); + if (len == 0) { + befs_error(sb, "Long symlink with illegal length"); link = ERR_PTR(-EIO); } else { - link[len - 1] = '\0'; + befs_debug(sb, "Follow long symlink"); + + link = kmalloc(len, GFP_NOFS); + if (!link) { + link = ERR_PTR(-ENOMEM); + } else if (befs_read_lsymlink(sb, data, link, len) != len) { + kfree(link); + befs_error(sb, "Failed to read entire long symlink"); + link = ERR_PTR(-EIO); + } else { + link[len - 1] = '\0'; + } } } else { link = befs_ino->i_data.symlink;