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

[Hangyu Hua]

On 2022/6/28 11:35, Tung Quang Nguyen wrote:
> > -----Original Message-----
> > From: Hangyu Hua <hbh25y@xxxxxxxxx>
> > Sent: Tuesday, June 28, 2022 9:59 AM
> > To: jmaloy@xxxxxxxxxx; ying.xue@xxxxxxxxxxxxx; davem@xxxxxxxxxxxxx; edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx;
> > pabeni@xxxxxxxxxx
> > Cc: netdev@xxxxxxxxxxxxxxx; tipc-discussion@xxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Hangyu Hua <hbh25y@xxxxxxxxx>
> > 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@xxxxxxxxx <mailto:hbh25y@xxxxxxxxx>>
> > ---
> >   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