Re: [PATCH net -v2] [BUGFIX] bonding: use local function pointer of bond->recv_probe in bond_handle_frame

David Miller
2011-10-19T04:14:47Z

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 19 Oct 2011 06:05:27 +0200

> Le jeudi 13 octobre 2011 à 11:04 +0900, Mitsuo Hayasaka a écrit :
>> The bond->recv_probe is called in bond_handle_frame() when
>> a packet is received, but bond_close() sets it to NULL. So,
>> a panic occurs when both functions work in parallel.
>>
>> Why this happen:
>> After null pointer check of bond->recv_probe, an sk_buff is
>> duplicated and bond->recv_probe is called in bond_handle_frame.
>> So, a panic occurs when bond_close() is called between the
>> check and call of bond->recv_probe.
>>
>> Patch:
>> This patch uses a local function pointer of bond->recv_probe
>> in bond_handle_frame(). So, it can avoid the null pointer
>> dereference.
>>
>>
>> Signed-off-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
...
> Sorry, I forgot to add my official ack. Even if not a perfect patch, its
> a step into right direction.
>
> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>

Thanks for reviewing Eric, applied.