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

[Herbert Xu]

On Tue, Oct 24, 2017 at 05:10:06PM +0200, Dmitry Vyukov wrote:
> On Tue, Oct 24, 2017 at 5:08 PM, syzbot
> <bot+413384116f7f7dab7903d54c53fc4af6a4441965@xxxxxxxxxxxxxxxxxxxxxxxxx>
> wrote:
> > Hello,
> >
> > syzkaller hit the following crash on
> > 02a2b05395dde2f49e7777b67b51a5fbc6606943
> > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
> > compiler: gcc (GCC) 7.1.1 20170620
> > .config is attached
> > Raw console output is attached.
> > C reproducer is attached
> > syzkaller reproducer is attached. See https://goo.gl/kgGztJ
> > for information about syzkaller reproducers
> 
> This also happened on more recent commits, including net-next
> 833e0e2f24fd0525090878f71e129a8a4cb8bf78 (Oct 10) with similar
> signature:

Unfortunately I cannot reproduce the crash with your reproducer.
Does it always crash for you?

> ------------[ cut here ]------------
> kernel BUG at net/key/af_key.c:2068!
> invalid opcode: 0000 [#1] SMP KASAN
> Dumping ftrace buffer:
>    (ftrace buffer empty)
> Modules linked in:
> CPU: 1 PID: 11011 Comm: syz-executor1 Not tainted 4.14.0-rc4+ #80
> Hardware name: Google Google Compute Engine/Google Compute Engine,
> BIOS Google 01/01/2011
> task: ffff8801d4ecc1c0 task.stack: ffff8801c13f8000
> RIP: 0010:pfkey_xfrm_policy2msg+0x209c/0x22b0 net/key/af_key.c:2068

This shows that you have a xfrm policy that has a bogus family
field in your policy database.  But it gives no clue as to how
it got there.

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