From e8766fc86b34d44a8c55a2f9d71da69e091b1ca4 Mon Sep 17 00:00:00 2001
From: Shan Wei <shanwei@cn.fujitsu.com>
Date: Tue, 10 Jun 2008 15:50:55 +0800
Subject: [PATCH] ipv6: Check the hop limit setting in ancillary data.

When specifing the outgoing hop limit as ancillary data for sendmsg(),
the kernel doesn't check the integer hop limit value as specified in
[RFC-3542] section 6.3.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
---
 net/ipv6/datagram.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index b9c2de84a8a2..0f0f94a40335 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -705,6 +705,11 @@ int datagram_send_ctl(struct net *net,
 			}
 
 			*hlimit = *(int *)CMSG_DATA(cmsg);
+			if (*hlimit < -1 || *hlimit > 0xff) {
+				err = -EINVAL;
+				goto exit_f;
+			}
+
 			break;
 
 		case IPV6_TCLASS:
-- 
2.30.2