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

On 2022/6/28 11:35, Tung Quang Nguyen wrote:

quoted

-----Original Message-----
From: Hangyu Hua <redacted>
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 <redacted>
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

quoted

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