tipc: fix socket list regression in new nl api

Commit 07f6c4bc (tipc: convert tipc reference table to use generic
rhashtable) introduced a problem with port listing in the new netlink
API. It broke the resume functionality resulting in a never ending
loop. This was caused by starting with the first hash table every time
subsequently never returning an empty skb (terminating).

This patch fixes the resume mechanism by keeping a logical reference
to the last hash table along with a logical reference to the socket
(port) that didn't fit in the previous message.

Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Richard Alpe 2015-01-16 12:30:40 +01:00 committed by David S. Miller
parent e445dd5f67
commit d6e164e321

View File

@ -2749,29 +2749,35 @@ int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb)
struct tipc_sock *tsk;
const struct bucket_table *tbl;
struct rhash_head *pos;
u32 prev_portid = cb->args[0];
u32 portid = prev_portid;
struct net *net = sock_net(skb->sk);
struct tipc_net *tn = net_generic(net, tipc_net_id);
int i;
u32 tbl_id = cb->args[0];
u32 prev_portid = cb->args[1];
rcu_read_lock();
tbl = rht_dereference_rcu((&tn->sk_rht)->tbl, &tn->sk_rht);
for (i = 0; i < tbl->size; i++) {
rht_for_each_entry_rcu(tsk, pos, tbl, i, node) {
for (; tbl_id < tbl->size; tbl_id++) {
rht_for_each_entry_rcu(tsk, pos, tbl, tbl_id, node) {
spin_lock_bh(&tsk->sk.sk_lock.slock);
portid = tsk->portid;
err = __tipc_nl_add_sk(skb, cb, tsk);
spin_unlock_bh(&tsk->sk.sk_lock.slock);
if (err)
break;
if (prev_portid && prev_portid != tsk->portid) {
spin_unlock_bh(&tsk->sk.sk_lock.slock);
continue;
}
prev_portid = portid;
err = __tipc_nl_add_sk(skb, cb, tsk);
if (err) {
prev_portid = tsk->portid;
spin_unlock_bh(&tsk->sk.sk_lock.slock);
goto out;
}
prev_portid = 0;
spin_unlock_bh(&tsk->sk.sk_lock.slock);
}
}
out:
rcu_read_unlock();
cb->args[0] = prev_portid;
cb->args[0] = tbl_id;
cb->args[1] = prev_portid;
return skb->len;
}