Re: connect() bug?

Alan Cox (alan@lxorguk.ukuu.org.uk)
Sat, 13 Sep 1997 16:03:33 +0100 (BST)


> Squid's config file has the comment:
> # Some systems (notably Linux) can not be relied upon to properly
> # time out connect(2) requests.
>
> Does anybody know if this is still correct? I find no mention of this bug
> on the connect(2) manpage, and I can't find connect in the kernel source at
> all!

There has never been such a bug in Linux. The squid authors got confused by
the fact Linux correctly follows the RFC's and takes far longer than BSD to
timeout connections. (BSD defaults to about 75 seconds we default to about
15 minutes). The BSD one is wrong (the max round trip time for a packet
in TCP is allowed to be 60 seconds, so a 3rd SYN with the first two dropped
would timeout in BSD if the rtt really was 60 seconds. This doesn't arise
too often on normal networks but will be an issue with earth->mars tcp/ip ;)

Alan