Re: [PATCH] Fix repeatable Oops on container destroy with conntrack

Alex Bligh
2011-09-13T20:44:44Z

Alexey / Pablo,

--On 12 September 2011 20:06:25 +0100 Alex Bligh <alex@alex.org.uk> wrote:

> Pablo,
>
> --On 12 September 2011 20:33:57 +0200 Pablo Neira Ayuso
> <pablo@netfilter.org> wrote:
>
>> Yes, this is what Alexey was pointing out in the previous email and
>> why he suggested to move it to nfnetlink_has_listeners (to cover the
>> expectation case).
>>
>> But you're right, we cannot move it to nfnetlink_has_listeners because
>> of the item->report case. Please, include the expectation part and
>> resend the patch.
>
> Thanks - see below

Is this new version OK? I am happy to adjust if not.

I think we ought to get /something/ in, because without anything it's
very simple to cause an oops and a resultant machine hang.

--
Alex Bligh

> Signed-off-by: Alex Bligh <alex@alex.org.uk>
> ---
> net/netfilter/nf_conntrack_netlink.c | 9 +++++++++
> 1 files changed, 9 insertions(+), 0 deletions(-)
>
> diff --git a/net/netfilter/nf_conntrack_netlink.c
> b/net/netfilter/nf_conntrack_netlink.c
> index 482e90c..f44d571 100644
> --- a/net/netfilter/nf_conntrack_netlink.c
> +++ b/net/netfilter/nf_conntrack_netlink.c
> @@ -570,6 +570,11 @@ ctnetlink_conntrack_event(unsigned int events,
> struct nf_ct_event *item)
> return 0;
>
> net = nf_ct_net(ct);
> +
> + /* container deinit, netlink may have died before
> death_by_timeout */
> + if (!net->nfnl)
> + return 0;
> +
> if (!item->report && !nfnetlink_has_listeners(net, group))
> return 0;
>
> @@ -1723,6 +1728,10 @@ ctnetlink_expect_event(unsigned int events, struct
> nf_exp_event *item)
> } else
> return 0;
>
> + /* container deinit, netlink may have died before
> death_by_timeout */
> + if (!net->nfnl)
> + return 0;
> +
> if (!item->report && !nfnetlink_has_listeners(net, group))
> return 0;
>
> --
> 1.7.5.4
>
>

--
Alex Bligh