From 5dc8ed79c1877d21c06f77b59b48513edbd5be2b Mon Sep 17 00:00:00 2001 From: Bill Sommerfeld Date: Fri, 4 Mar 2016 14:47:21 -0800 Subject: [PATCH] udp6: fix UDP/IPv6 encap resubmit path Orabug: 25308049 [ Upstream commit 59dca1d8a6725a121dae6c452de0b2611d5865dc ] IPv4 interprets a negative return value from a protocol handler as a request to redispatch to a new protocol. In contrast, IPv6 interprets a negative value as an error, and interprets a positive value as a request for redispatch. UDP for IPv6 was unaware of this difference. Change __udp6_lib_rcv() to return a positive value for redispatch. Note that the socket's encap_rcv hook still needs to return a negative value to request dispatch, and in the case of IPv6 packets, adjust IP6CB(skb)->nhoff to identify the byte containing the next protocol. Signed-off-by: Bill Sommerfeld Signed-off-by: David S. Miller Signed-off-by: Sasha Levin (cherry picked from commit 6def7a990b10af3532caed172e7ada9dbb596a53) Signed-off-by: Dhaval Giani --- net/ipv6/udp.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 7333f3575fc5..d28b2a1ab0e5 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -913,11 +913,9 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, ret = udpv6_queue_rcv_skb(sk, skb); sock_put(sk); - /* a return value > 0 means to resubmit the input, but - * it wants the return to be -protocol, or 0 - */ + /* a return value > 0 means to resubmit the input */ if (ret > 0) - return -ret; + return ret; return 0; } -- 2.50.1