From: David Miller <davem@davemloft.net>
To: jiri@resnulli.us
Cc: netdev@vger.kernel.org, jhs@mojatatu.com,
xiyou.wangcong@gmail.com, kubakici@wp.pl, mlxsw@mellanox.com
Subject: Re: [patch net] net: sched: fix use-after-free in tcf_action_destroy and tcf_del_walker
Date: Wed, 13 Sep 2017 13:59:48 -0700 (PDT) [thread overview]
Message-ID: <20170913.135948.629502810637692498.davem@davemloft.net> (raw)
In-Reply-To: <20170913205006.GD1981@nanopsycho>
From: Jiri Pirko <jiri@resnulli.us>
Date: Wed, 13 Sep 2017 22:50:06 +0200
> Wed, Sep 13, 2017 at 06:34:28PM CEST, davem@davemloft.net wrote:
>>From: Jiri Pirko <jiri@resnulli.us>
>>Date: Wed, 13 Sep 2017 17:32:37 +0200
>>
>>> From: Jiri Pirko <jiri@mellanox.com>
>>>
>>> Recent commit d7fb60b9cafb ("net_sched: get rid of tcfa_rcu") removed
>>> freeing in call_rcu, which changed already existing hard-to-hit
>>> race condition into 100% hit:
>>>
>>> [ 598.599825] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
>>> [ 598.607782] IP: tcf_action_destroy+0xc0/0x140
>>>
>>> Or:
>>>
>>> [ 40.858924] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
>>> [ 40.862840] IP: tcf_generic_walker+0x534/0x820
>>>
>>> Fix this by storing the ops and use them directly for module_put call.
>>>
>>> Fixes: a85a970af265 ("net_sched: move tc_action into tcf_common")
>>> Signed-off-by: Jiri Pirko <jiri@mellanox.com>
>>
>>Applied, thanks Jiri.
>
> Oh, I forgot to mention, this would be nice to push to stable.
Ok, queued up.
prev parent reply other threads:[~2017-09-13 20:59 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-13 15:32 [patch net] net: sched: fix use-after-free in tcf_action_destroy and tcf_del_walker Jiri Pirko
2017-09-13 16:34 ` David Miller
2017-09-13 20:50 ` Jiri Pirko
2017-09-13 20:59 ` David Miller [this message]
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