2.1.32: ICMP port unreach not propagated?

Olaf Kirch (okir@monad.swb.de)
Mon, 07 Apr 1997 23:47:10 +0200


Hi all,

When trying out 2.1.32, I've been plagued by boots that seemed to hang
mysteriously during the init phase. The problem was that bash tried
to contact ypbind at a stage where loopback was up, but portmap wasn't
running. As far as I have traced it now, the error is eing propagated
to the UDP layer alright, but gets dropped there because it can't find
a matching socket (the UDP socket is unconnected, FWIW).

While looking at the ICMP handling, I found another possible trouble
spot in icmp.c's handling of unreachables. When receiving a broadcast
ICMP it intends to drop it. While it does free the skb, it does not
return immediately, so later code will get to play with corrupted memory.

Cheers
Olaf

-- 
Olaf Kirch         |  --- o --- Nous sommes du soleil we love when we play
okir@monad.swb.de  |    / | \   sol.dhoop.naytheet.ah kin.ir.samse.qurax
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