tipc: remove joining group member from congested list

When we receive a JOIN message from a peer member, the message may
contain an advertised window value ADV_IDLE that permits removing the
member in question from the tipc_group::congested list. However, since
the removal has been made conditional on that the advertised window is
*not* ADV_IDLE, we miss this case. This has the effect that a sender
sometimes may enter a state of permanent, false, broadcast congestion.

We fix this by unconditinally removing the member from the congested
list before calling tipc_member_update(), which might potentially sort
it into the list again.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 4 deletions

diff --git a/net/tipc/group.c b/net/tipc/group.c
index bbc004eaa31a..7ebbdeb2a90e 100644
--- a/net/tipc/group.c
+++ b/net/tipc/group.c
@@ -689,10 +689,8 @@ void tipc_group_proto_rcv(struct tipc_group *grp, bool *usr_wakeup,
                         msg_set_grp_bc_seqno(ehdr, m->bc_syncpt);
                         __skb_queue_tail(inputq, m->event_msg);
                 }
-                if (m->window < ADV_IDLE)
-                        tipc_group_update_member(m, 0);
-                else
-                        list_del_init(&m->congested);
+                list_del_init(&m->congested);
+                tipc_group_update_member(m, 0);
                 return;
         case GRP_LEAVE_MSG:
                 if (!m)