sit: fix an oops when IFLA_IPTUN_PROTO is not set
The use of this attribute has been added in 32b8a8e59c9c (sit: add IPv4 over
IPv4 support). It is optional, by default proto is IPPROTO_IPV6.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 6cee844..f639866 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -1296,7 +1296,7 @@
{
u8 proto;
- if (!data)
+ if (!data || !data[IFLA_IPTUN_PROTO])
return 0;
proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);