Merge branch 'flow_dissector-fixes'

Tom Herbert says:

====================
flow_dissector: Flow dissector fixes

This patch set fixes some basic issues with __skb_flow_dissect function.

Items addressed:
  - Cleanup control flow in the function; in particular eliminate a
    bunch of goto's and implement a simplified control flow model
  - Add limits for number of encapsulations and headers that can be
    dissected

v2:
  - Simplify the logic for limits on flow dissection. Just set the
    limit based on the number of headers the flow dissector can
    processes. The accounted headers includes encapsulation headers,
    extension headers, or other shim headers.

Tested:

Ran normal traffic, GUE, and VXLAN traffic.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/flow_dissector.h

@@ -19,6 +19,14 @@ struct flow_dissector_key_control {
 #define FLOW_DIS_FIRST_FRAG	BIT(1)
 #define FLOW_DIS_ENCAPSULATION	BIT(2)
 
+enum flow_dissect_ret {
+	FLOW_DISSECT_RET_OUT_GOOD,
+	FLOW_DISSECT_RET_OUT_BAD,
+	FLOW_DISSECT_RET_PROTO_AGAIN,
+	FLOW_DISSECT_RET_IPPROTO_AGAIN,
+	FLOW_DISSECT_RET_CONTINUE,
+};
+
 /**
  * struct flow_dissector_key_basic:
  * @thoff: Transport header offset