Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932480Ab1DLOon (ORCPT ); Tue, 12 Apr 2011 10:44:43 -0400 Received: from kroah.org ([198.145.64.141]:57755 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932387Ab1DLOim (ORCPT ); Tue, 12 Apr 2011 10:38:42 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Tue Apr 12 07:35:56 2011 Message-Id: <20110412143556.735835945@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Tue, 12 Apr 2011 07:35:11 -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, Vasiliy Kulikov , Changli Gao , Patrick McHardy Subject: [082/105] netfilter: ipt_CLUSTERIP: fix buffer overflow In-Reply-To: <20110412143613.GA19478@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1607 Lines: 47 2.6.38-stable review patch. If anyone has any objections, please let us know. ------------------ From: Vasiliy Kulikov commit 961ed183a9fd080cf306c659b8736007e44065a5 upstream. 'buffer' string is copied from userspace. It is not checked whether it is zero terminated. This may lead to overflow inside of simple_strtoul(). Changli Gao suggested to copy not more than user supplied 'size' bytes. It was introduced before the git epoch. Files "ipt_CLUSTERIP/*" are root writable only by default, however, on some setups permissions might be relaxed to e.g. network admin user. Signed-off-by: Vasiliy Kulikov Acked-by: Changli Gao Signed-off-by: Patrick McHardy Signed-off-by: Greg Kroah-Hartman --- net/ipv4/netfilter/ipt_CLUSTERIP.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/net/ipv4/netfilter/ipt_CLUSTERIP.c +++ b/net/ipv4/netfilter/ipt_CLUSTERIP.c @@ -669,8 +669,11 @@ static ssize_t clusterip_proc_write(stru char buffer[PROC_WRITELEN+1]; unsigned long nodenum; - if (copy_from_user(buffer, input, PROC_WRITELEN)) + if (size > PROC_WRITELEN) + return -EIO; + if (copy_from_user(buffer, input, size)) return -EFAULT; + buffer[size] = 0; if (*buffer == '+') { nodenum = simple_strtoul(buffer+1, NULL, 10); -- 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/