From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754726Ab3KAVoE (ORCPT ); Fri, 1 Nov 2013 17:44:04 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:54545 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751153Ab3KAVn6 (ORCPT ); Fri, 1 Nov 2013 17:43:58 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mathias Krause , "David S. Miller" Subject: [ 16/32] connector: use nlmsg_len() to check message length Date: Fri, 1 Nov 2013 14:43:27 -0700 Message-Id: <20131101214317.517914955@linuxfoundation.org> X-Mailer: git-send-email 1.8.4.3.gca3854a In-Reply-To: <20131101214313.735463599@linuxfoundation.org> References: <20131101214313.735463599@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Krause [ Upstream commit 162b2bedc084d2d908a04c93383ba02348b648b0 ] The current code tests the length of the whole netlink message to be at least as long to fit a cn_msg. This is wrong as nlmsg_len includes the length of the netlink message header. Use nlmsg_len() instead to fix this "off-by-NLMSG_HDRLEN" size check. Signed-off-by: Mathias Krause Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/connector/connector.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/connector/connector.c +++ b/drivers/connector/connector.c @@ -157,17 +157,18 @@ static int cn_call_callback(struct sk_bu static void cn_rx_skb(struct sk_buff *__skb) { struct nlmsghdr *nlh; - int err; struct sk_buff *skb; + int len, err; skb = skb_get(__skb); if (skb->len >= NLMSG_SPACE(0)) { nlh = nlmsg_hdr(skb); + len = nlmsg_len(nlh); - if (nlh->nlmsg_len < sizeof(struct cn_msg) || + if (len < (int)sizeof(struct cn_msg) || skb->len < nlh->nlmsg_len || - nlh->nlmsg_len > CONNECTOR_MAX_MSG_SIZE) { + len > CONNECTOR_MAX_MSG_SIZE) { kfree_skb(skb); return; }