Re: [6/6] 2.6.21-rc4: known regressions

David Miller
2007-03-20T02:38:31Z

From: Adrian Bunk <bunk@stusta.de>
Date: Sun, 18 Mar 2007 19:49:38 +0100

> Subject : ipv6 crash
> References : http://lkml.org/lkml/2007/3/10/2
> Submitter : Len Brown <lenb@kernel.org>
> Status : unknown

This is caused by some problem in the router round-robin code in
net/ipv6/route.c:rt6_select()

Somehow it NULLs out fn->leaf, and then fib6_add_1() crashes
dererencing that NULL pointer as is seen in the report.

Deleting the router round-robin list mangling code in rt6_select()
makes the crash go away, but such a change causes regressions in the
ipv6 conformance tests.

Thomas Graf discovered this bug some time ago, but we still
haven't come up with a fix suitable for upstream :-/

This bug has been there for a very long time and is not a regression
of 2.6.21

I'll see if I can come up with something to fix this properly.