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

On 6/27/22 22:59, Hangyu Hua wrote:
> 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>
> ---
>   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;
>   	dom = peer->domain;
>   	if (dom)
Acked-by: Jon Maloy <jmaloy@redhat.com>