[2.6 PATCH] IPV6: Check length of optval provided by user in setsockopt()

[Wang Chen <wangchen@cn.fujitsu.com>]

Check length of setsockopt's optval, which provided by user, before copy it
from user space.

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
---
 net/ipv6/ipv6_sockglue.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index bf2a686..1ad0ac9 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -557,6 +557,9 @@ done:
 	{
 		struct ipv6_mreq mreq;
 
+		if (optlen != sizeof(struct ipv6_mreq))
+			goto e_inval;
+
 		retv = -EPROTO;
 		if (inet_sk(sk)->is_icsk)
 			break;
@@ -595,6 +598,9 @@ done:
 		struct group_req greq;
 		struct sockaddr_in6 *psin6;
 
+		if (optlen != sizeof(struct group_req))
+			goto e_inval;
+
 		retv = -EFAULT;
 		if (copy_from_user(&greq, optval, sizeof(struct group_req)))
 			break;
-- 
1.5.3.4