From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759419AbdEVMJ4 (ORCPT ); Mon, 22 May 2017 08:09:56 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:35307 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758595AbdEVMJo (ORCPT ); Mon, 22 May 2017 08:09:44 -0400 Date: Mon, 22 May 2017 15:08:31 +0300 From: Dan Carpenter To: Mike Marshall , Martin Brandenburg Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH] orangefs: off by ones in xattr size checks Message-ID: <20170522120831.GA27513@elgon.mountain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: userv0021.oracle.com [156.151.31.71] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A previous patch which claimed to remove off by ones actually introduced them. strlen() returns the length of the string not including the NUL character. We are using strcpy() to copy "name" into a buffer which is ORANGEFS_MAX_XATTR_NAMELEN characters long. We should make sure to leave space for the NUL, otherwise we're writing one character beyond the end of the buffer. Fixes: e675c5ec51fe ("orangefs: clean up oversize xattr validation") Signed-off-by: Dan Carpenter diff --git a/fs/orangefs/xattr.c b/fs/orangefs/xattr.c index 237c9c04dc3b..a34b25be39c5 100644 --- a/fs/orangefs/xattr.c +++ b/fs/orangefs/xattr.c @@ -76,7 +76,7 @@ ssize_t orangefs_inode_getxattr(struct inode *inode, const char *name, if (S_ISLNK(inode->i_mode)) return -EOPNOTSUPP; - if (strlen(name) > ORANGEFS_MAX_XATTR_NAMELEN) + if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN) return -EINVAL; fsuid = from_kuid(&init_user_ns, current_fsuid()); @@ -169,7 +169,7 @@ static int orangefs_inode_removexattr(struct inode *inode, const char *name, struct orangefs_kernel_op_s *new_op = NULL; int ret = -ENOMEM; - if (strlen(name) > ORANGEFS_MAX_XATTR_NAMELEN) + if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN) return -EINVAL; down_write(&orangefs_inode->xattr_sem); @@ -233,7 +233,7 @@ int orangefs_inode_setxattr(struct inode *inode, const char *name, if (size > ORANGEFS_MAX_XATTR_VALUELEN) return -EINVAL; - if (strlen(name) > ORANGEFS_MAX_XATTR_NAMELEN) + if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN) return -EINVAL; internal_flag = convert_to_internal_xattr_flags(flags);