tipc: lock wakeup & inputq at tipc_link_reset()

In tipc_link_reset() we copy the wakeup queue to input queue using
skb_queue_splice_init(link->wakeupq, link->inputq).
This is performed without holding any locks. The lists might be
simultaneously be accessed by other cpu threads in tipc_sk_rcv(),
something leading to to random missing packets.

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Parthasarathy Bhuvaragan 2018-09-25 22:09:10 +02:00 committed by David S. Miller
parent 94b6ddce71
commit 3f32d0be6c

View File

@ -841,9 +841,14 @@ void tipc_link_reset(struct tipc_link *l)
l->in_session = false;
l->session++;
l->mtu = l->advertised_mtu;
spin_lock_bh(&l->wakeupq.lock);
spin_lock_bh(&l->inputq->lock);
skb_queue_splice_init(&l->wakeupq, l->inputq);
spin_unlock_bh(&l->inputq->lock);
spin_unlock_bh(&l->wakeupq.lock);
__skb_queue_purge(&l->transmq);
__skb_queue_purge(&l->deferdq);
skb_queue_splice_init(&l->wakeupq, l->inputq);
__skb_queue_purge(&l->backlogq);
l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;