Re: kernel BUG at net/key/af_key.c:LINE!

From: Herbert Xu
Date: Thu Nov 09 2017 - 06:39:28 EST


On Wed, Nov 08, 2017 at 08:59:15AM +0100, Dmitry Vyukov wrote:
>
> Also the repro needs to be compiled with -m32 (but it does not compile
> without it due to missing __NR_mmap2, so I guess you passed -m32).

OK that's what I was missing. I had hacked it to compile in
64-bit :)

However, I still don't understand why it's crashing yet. What is
clear is that we're getting a socket policy with xp->family set
to zero, and the policy is created via the xfrm code path (as
opposed to af_key).

The xfrm code path is meant to forbid the creation of such a policy.
I don't currently see how this is bypassing that check. But
clearly it has found a way through the check since it's crashing.

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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