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	Web pdp-10.trailing-edge.com

Problem:
	Load goes up to 50; have to crash system.

Why:	
	Host PS1.CS.CMU.EDU sends you a bogus TCP packet where
	the length of the IP plus TCP headers is larger than the
	length of the whole IP packet.  This causes the TCP
	options processing code to loop forever (in some cases).

Fix:
	In TCPTCP, add the following code to make sure the
	packet is big enough for the headers.

Note:
	I haven't had a chance to test this out yet, but its
	pretty straight forward and should help if you're having
	the same problem.  
---------------
INPRO2:
IFN NICSW,<	
	LOAD T1,PIPL,(PKT)	; Get total IP length in bytes
	LOAD T2,PIDO,(PKT)	; Get IP header length in words
	LOAD T3,PTDO,(TPKT)	; Get TCP header length in words
	ADD T2,T3		; Add header lengths
	LSH T2,2		; Convert to bytes
	CAML T1,T2		; Is packet big enough for headers?
	 JRST INPRO3		; Yes, continue then
;flush bogus packet
	AOS BADPCT		; Count bad packets
	CALL RETPKT		; Return the packet 
	JRST INPRO0		; And do next packet
INPRO3:
>;IFN NICSW