| From foo@baz Sat Apr 16 22:36:37 PDT 2016 |
| From: Bill Sommerfeld <wsommerfeld@google.com> |
| Date: Fri, 4 Mar 2016 14:47:21 -0800 |
| Subject: udp6: fix UDP/IPv6 encap resubmit path |
| Status: RO |
| Content-Length: 1318 |
| Lines: 40 |
| |
| From: Bill Sommerfeld <wsommerfeld@google.com> |
| |
| [ 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 <wsommerfeld@google.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/ipv6/udp.c | 6 ++---- |
| 1 file changed, 2 insertions(+), 4 deletions(-) |
| |
| --- a/net/ipv6/udp.c |
| +++ b/net/ipv6/udp.c |
| @@ -868,11 +868,9 @@ int __udp6_lib_rcv(struct sk_buff *skb, |
| 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; |
| } |
