[IPV6]: Ensure to truncate result and return full length for sticky options.
Bug noticed by Chris Wright <chrisw@sous-sol.org>.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index eceed09..1d56b46 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -825,9 +825,9 @@
return 0;
len = min_t(unsigned int, len, ipv6_optlen(hdr));
- if (copy_to_user(optval, hdr, ipv6_optlen(hdr)))
+ if (copy_to_user(optval, hdr, len));
return -EFAULT;
- return len;
+ return ipv6_optlen(hdr);
}
static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,