Re: [netfilter-core] 2.4.23/others and ip_conntrack causing hangs

From: Rusty Russell (rusty_at_rustcorp.com.au)
Date: 12/01/03

  • Next message: Pete Zaitcev: "Re: [USB] Fix connect/disconnect race" 
    To: James Bourne <jbourne@hardrock.org>
Date:	Mon, 01 Dec 2003 11:22:59 +1100

    In message <Pine.LNX.4.44.0311301204520.2148-100000@cafe.hardrock.org> you writ
    e:
    > Hi all,
    > I wanted to bring up an issue with ip_conntrack in 2.4.23, 2.4.22, and at
    > least 2.4.21 (sorry, didn't try 2.4.20).
    >
    > The issue is that as long as there are connections being tracked, the
    > ip_conntrack module will not unload. I can understand why this might be,
    > but the problem is that ip_conntrack will hang rmmod and modprobe -r until
    > such time as all the connections have been closed.
    >
    > I think we need something like an ip_conntrack_flush or else completely drop
    > the connections when the module is unloaded (as previously done) as this
    > becomes an issue for people who need to drop their ip_tables and reload the
    > modules (perhaps to correct other issues) especially ip_conntrack...

    Um, this is exactly what the code does on unload: an explicit flush.

    Unfortunately, some packets are still referencing connections, so the
    module *cannot* go away. Figuring out exactly where the packets are
    referenced from is the fun part. We explicitly drop the reference in
    ip_local_deliver_finish() for exactly this reason. Perhaps there is
    somewhere else we should be doing the same thing.

    Hope that clarifies,
    Rusty. 

    --
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
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