net: filter: Use WARN_RATELIMIT

A mis-configured filter can spam the logs with lots of stack traces.

Rate-limit the warnings and add printout of the bogus filter information.
Original-patch-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/filter.c

@@ -350,7 +350,9 @@ unsigned int sk_run_filter(const struct sk_buff *skb,
 			continue;
 		}
 		default:
-			WARN_ON(1);
+			WARN_RATELIMIT(1, "Unknown code:%u jt:%u tf:%u k:%u\n",
+				       fentry->code, fentry->jt,
+				       fentry->jf, fentry->k);
 			return 0;
 		}
 	}