[PATCH] net: flow_dissector: fix thoff for IPPROTO_AH

Eric Dumazet
2013-09-26T15:44:09Z

From: Eric Dumazet <edumazet@google.com>

In commit 8ed781668dd49 ("flow_keys: include thoff into flow_keys for
later usage"), we missed that existing code was using nhoff as a
temporary variable that could not always contain transport header
offset.

This is not a problem for TCP/UDP because port offset (@poff)
is 0 for these protocols.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Nikolay Aleksandrov <nikolay@redhat.com>
---
net/core/flow_dissector.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 1929af8..8d7d0dd 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -154,8 +154,8 @@ ipv6:
if (poff >= 0) {
__be32 *ports, _ports;

- nhoff += poff;
- ports = skb_header_pointer(skb, nhoff, sizeof(_ports), &_ports);
+ ports = skb_header_pointer(skb, nhoff + poff,
+ sizeof(_ports), &_ports);
if (ports)
flow->ports = *ports;
}