From: Eli Cooper <[email protected]> commit 23f4ffedb7d751c7e298732ba91ca75d224bc1a6 upstream.
skb->cb may contain data from previous layers. In the observed scenario, the garbage data were misinterpreted as IP6CB(skb)->frag_max_size, so that small packets sent through the tunnel are mistakenly fragmented. This patch unconditionally clears the control buffer in ip6tunnel_xmit(), which affects ip6_tunnel, ip6_udp_tunnel and ip6_gre. Currently none of these tunnels set IP6CB(skb)->flags, otherwise it needs to be done earlier. Cc: [email protected] Signed-off-by: Eli Cooper <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Willy Tarreau <[email protected]> --- include/net/ip6_tunnel.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/net/ip6_tunnel.h b/include/net/ip6_tunnel.h index 4da5de1..b140c60 100644 --- a/include/net/ip6_tunnel.h +++ b/include/net/ip6_tunnel.h @@ -75,6 +75,7 @@ static inline void ip6tunnel_xmit(struct sk_buff *skb, struct net_device *dev) int pkt_len, err; nf_reset(skb); + memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); pkt_len = skb->len; err = ip6_local_out(skb); -- 2.8.0.rc2.1.gbe9624a
