From: Bill Sommerfeld Date: Fri, 4 Mar 2016 22:47:21 +0000 (-0800) Subject: udp6: fix UDP/IPv6 encap resubmit path X-Git-Tag: firefly_0821_release~176^2~4^2~49^2~97 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=8a2226c17e0e2256f71e6b3175b6d3455b479f02;p=firefly-linux-kernel-4.4.55.git udp6: fix UDP/IPv6 encap resubmit path [ 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: Greg Kroah-Hartman --- diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 9da3287a3923..1e293a552693 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -916,11 +916,9 @@ 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; }