Re: [PATCH] net: tipc: fix possible infoleak in tipc_mon_rcv()

[Hangyu Hua <hbh25y@gmail.com>]

On 2022/6/28 11:35, Tung Quang Nguyen wrote:
>> -----Original Message-----
>> From: Hangyu Hua <hbh25y@gmail.com>
>> Sent: Tuesday, June 28, 2022 9:59 AM
>> To: jmaloy@redhat.com; ying.xue@windriver.com; davem@davemloft.net; edumazet@google.com; kuba@kernel.org;
>> pabeni@redhat.com
>> Cc: netdev@vger.kernel.org; tipc-discussion@lists.sourceforge.net; linux-kernel@vger.kernel.org; Hangyu Hua <hbh25y@gmail.com>
>> Subject: [PATCH] net: tipc: fix possible infoleak in tipc_mon_rcv()
>> 
>> dom_bef is use to cache current domain record only if current domain
>> exists. But when current domain does not exist, dom_bef will still be used
>> in mon_identify_lost_members. This may lead to an information leak.
>> 
>> Fix this by adding a memset before using dom_bef.
>> 
>> Fixes: 35c55c9877f8 ("tipc: add neighbor monitoring framework")
>> Signed-off-by: Hangyu Hua <hbh25y@gmail.com <mailto:hbh25y@gmail.com>>
>> ---
>>  net/tipc/monitor.c | 1 +
>>  1 file changed, 1 insertion(+)
>> 
>> diff --git a/net/tipc/monitor.c b/net/tipc/monitor.c
>> index 2f4d23238a7e..67084e5aa15c 100644
>> --- a/net/tipc/monitor.c
>> +++ b/net/tipc/monitor.c
>> @@ -534,6 +534,7 @@ void tipc_mon_rcv(struct net *net, void *data, u16 dlen, u32 addr,
>>        state->peer_gen = new_gen;
>> 
>>        /* Cache current domain record for later use */
>> +     memset(&dom_bef, 0, sizeof(dom_bef));
>>        dom_bef.member_cnt = 0;
> Please remove /dom_bef.member_cnt = 0;/ if memset() is used instead.

I get it. I will send a v2.

Thanks,
Hangyu

>>        dom = peer->domain;
>>        if (dom)
>> --
>> 2.25.1