Subject: [PATCH 13/17] tipc: purge deferredq list for each grp member in tipc_group_delete

From: Xin Long <[email-masked]>
Date: Sun, 16 Jun 2019 17:24:07 +0800

[ Upstream commit 5cf02612b33f104fe1015b2dfaf1758ad3675588 ]

Syzbot reported a memleak caused by grp members' deferredq list not
purged when the grp is be deleted.

The issue occurs when more(msg_grp_bc_seqno(hdr), m->bc_rcv_nxt) in
tipc_group_filter_msg() and the skb will stay in deferredq.

So fix it by calling __skb_queue_purge for each member's deferredq
in tipc_group_delete() when a tipc sk leaves the grp.

Fixes: b87a5ea31c93 ("tipc: guarantee group unicast doesn't bypass group broadcast")
Reported-by: [email-masked]
Signed-off-by: Xin Long <[email-masked]>
Acked-by: Ying Xue <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 net/tipc/group.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/tipc/group.c b/net/tipc/group.c
index 06fee142f09f..3ee93b5c19b6 100644
--- a/net/tipc/group.c
+++ b/net/tipc/group.c
@@ -218,6 +218,7 @@ void tipc_group_delete(struct net *net, struct tipc_group *grp)
 
 	rbtree_postorder_for_each_entry_safe(m, tmp, tree, tree_node) {
 		tipc_group_proto_xmit(grp, m, GRP_LEAVE_MSG, &xmitq);
+		__skb_queue_purge(&m->deferredq);
 		list_del(&m->list);
 		kfree(m);
 	}
-- 
2.20.1