net: psample: Fix netlink skb length with tunnel info

Currently, the psample netlink skb is allocated with a size that does not account for the nested 'PSAMPLE_ATTR_TUNNEL' attribute and the padding required for the 64-bit attribute 'PSAMPLE_TUNNEL_KEY_ATTR_ID'. This can result in failure to add attributes to the netlink skb due to insufficient tail room. The following error message is printed to the kernel log: "Could not create psample log message".

Fix this by adjusting the allocation size to take into account the nested attribute and the padding.

---
 net/psample/psample.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index 33e238c965bd..482c07f2766b 100644
@@ -309,10 +309,10 @@ static int psample_tunnel_meta_len(struct ip_tunnel_info *tun_info)
 	unsigned short tun_proto = ip_tunnel_info_af(tun_info);
 	const struct ip_tunnel_key *tun_key = &tun_info->key;
 	int tun_opts_len = tun_info->options_len;
-	int sum = 0;
+	int sum = nla_total_size(0);	/* PSAMPLE_ATTR_TUNNEL */
 
 	if (tun_key->tun_flags & TUNNEL_KEY)
-		sum += nla_total_size(sizeof(u64));
+		sum += nla_total_size_64bit(sizeof(u64));
 
 	if (tun_info->mode & IP_TUNNEL_INFO_BRIDGE)
 		sum += nla_total_size(0);

2.26.2