From: William Tu <u9012063@gmail.com>
Date: Tue, 24 Apr 2018 23:46:59 -0700
Subject: bpf: clear the ip_tunnel_info.
Patch-mainline: v4.17-rc4
Git-commit: 5540fbf43845868defcb599ec91c678275a20671
References: bsc#1109837

The percpu metadata_dst might carry the stale ip_tunnel_info
and cause incorrect behavior.  When mixing tests using ipv4/ipv6
bpf vxlan and geneve tunnel, the ipv6 tunnel info incorrectly uses
ipv4's src ip addr as its ipv6 src address, because the previous
tunnel info does not clean up.  The patch zeros the fields in
ip_tunnel_info.

Signed-off-by: William Tu <u9012063@gmail.com>
Reported-by: Yifeng Sun <pkusunyifeng@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/core/filter.c |    1 +
 1 file changed, 1 insertion(+)

--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3226,6 +3226,7 @@ BPF_CALL_4(bpf_skb_set_tunnel_key, struc
 	skb_dst_set(skb, (struct dst_entry *) md);
 
 	info = &md->u.tun_info;
+	memset(info, 0, sizeof(*info));
 	info->mode = IP_TUNNEL_INFO_TX;
 
 	info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;