Commit 23d8335d authored by Jon Paul Maloy's avatar Jon Paul Maloy Committed by David S. Miller
Browse files

tipc: remove implicit message delivery in node_unlock() 



After the most recent changes, all access calls to a link which
may entail addition of messages to the link's input queue are
postpended by an explicit call to tipc_sk_rcv(), using a reference
to the correct queue.

This means that the potentially hazardous implicit delivery, using
tipc_node_unlock() in combination with a binary flag and a cached
queue pointer, now has become redundant.

This commit removes this implicit delivery mechanism both for regular
data messages and for binding table update messages.

Tested-by: default avatarYing Xue <ying.xue@windriver.com>
Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 598411d7

net/tipc/link.c

+3 −18
Original line number Diff line number Diff line
@@ -559,8 +559,6 @@ void link_prepare_wakeup(struct tipc_link *l) 
			break;

		skb_unlink(skb, &l->wakeupq);

		skb_queue_tail(l->inputq, skb);

		l->owner->inputq = l->inputq;

		l->owner->action_flags |= TIPC_MSG_EVT;

	}

}
@@ -598,8 +596,6 @@ void tipc_link_purge_queues(struct tipc_link *l_ptr) 


void tipc_link_reset(struct tipc_link *l)

{

	struct tipc_node *owner = l->owner;



	tipc_link_fsm_evt(l, LINK_RESET_EVT);



	/* Link is down, accept any session */
@@ -611,14 +607,10 @@ void tipc_link_reset(struct tipc_link *l) 
	/* Prepare for renewed mtu size negotiation */

	l->mtu = l->advertised_mtu;



	/* Clean up all queues, except inputq: */

	/* Clean up all queues: */

	__skb_queue_purge(&l->transmq);

	__skb_queue_purge(&l->deferdq);

	if (!owner->inputq)

		owner->inputq = l->inputq;

	skb_queue_splice_init(&l->wakeupq, owner->inputq);

	if (!skb_queue_empty(owner->inputq))

		owner->action_flags |= TIPC_MSG_EVT;

	skb_queue_splice_init(&l->wakeupq, l->inputq);



	tipc_link_purge_backlog(l);

	kfree_skb(l->reasm_buf);
@@ -972,7 +964,6 @@ static bool tipc_data_input(struct tipc_link *link, struct sk_buff *skb) 
{

	struct tipc_node *node = link->owner;

	struct tipc_msg *msg = buf_msg(skb);

	u32 dport = msg_destport(msg);



	switch (msg_user(msg)) {

	case TIPC_LOW_IMPORTANCE:
@@ -980,17 +971,11 @@ static bool tipc_data_input(struct tipc_link *link, struct sk_buff *skb) 
	case TIPC_HIGH_IMPORTANCE:

	case TIPC_CRITICAL_IMPORTANCE:

	case CONN_MANAGER:

		if (tipc_skb_queue_tail(link->inputq, skb, dport)) {

			node->inputq = link->inputq;

			node->action_flags |= TIPC_MSG_EVT;

		}

		skb_queue_tail(link->inputq, skb);

		return true;

	case NAME_DISTRIBUTOR:

		node->bclink.recv_permitted = true;

		node->namedq = link->namedq;

		skb_queue_tail(link->namedq, skb);

		if (skb_queue_len(link->namedq) == 1)

			node->action_flags |= TIPC_NAMED_MSG_EVT;

		return true;

	case MSG_BUNDLER:

	case TUNNEL_PROTOCOL:

net/tipc/msg.h

+0 −22
Original line number Diff line number Diff line
@@ -862,28 +862,6 @@ static inline struct sk_buff *tipc_skb_dequeue(struct sk_buff_head *list, 
	return skb;

}



/* tipc_skb_queue_tail(): add buffer to tail of list;

 * @list: list to be appended to

 * @skb: buffer to append. Always appended

 * @dport: the destination port of the buffer

 * returns true if dport differs from previous destination

 */

static inline bool tipc_skb_queue_tail(struct sk_buff_head *list,

				       struct sk_buff *skb, u32 dport)

{

	struct sk_buff *_skb = NULL;

	bool rv = false;



	spin_lock_bh(&list->lock);

	_skb = skb_peek_tail(list);

	if (!_skb || (msg_destport(buf_msg(_skb)) != dport) ||

	    (skb_queue_len(list) > 32))

		rv = true;

	__skb_queue_tail(list, skb);

	spin_unlock_bh(&list->lock);

	return rv;

}



/* tipc_skb_queue_sorted(); sort pkt into list according to sequence number

 * @list: list to be appended to

 * @skb: buffer to add

net/tipc/node.c

+7 −19
Original line number Diff line number Diff line
@@ -873,10 +873,8 @@ static void node_lost_contact(struct tipc_node *n_ptr, 
				      SHORT_H_SIZE, 0, tn->own_addr,

				      conn->peer_node, conn->port,

				      conn->peer_port, TIPC_ERR_NO_NODE);

		if (likely(skb)) {

		if (likely(skb))

			skb_queue_tail(inputq, skb);

			n_ptr->action_flags |= TIPC_MSG_EVT;

		}

		list_del(&conn->list);

		kfree(conn);

	}
@@ -923,27 +921,20 @@ void tipc_node_unlock(struct tipc_node *node) 
	u32 flags = node->action_flags;

	u32 link_id = 0;

	struct list_head *publ_list;

	struct sk_buff_head *inputq = node->inputq;

	struct sk_buff_head *namedq;



	if (likely(!flags || (flags == TIPC_MSG_EVT))) {

		node->action_flags = 0;

	if (likely(!flags)) {

		spin_unlock_bh(&node->lock);

		if (flags == TIPC_MSG_EVT)

			tipc_sk_rcv(net, inputq);

		return;

	}



	addr = node->addr;

	link_id = node->link_id;

	namedq = node->namedq;

	publ_list = &node->publ_list;



	node->action_flags &= ~(TIPC_MSG_EVT |

				TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |

	node->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |

				TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP |

				TIPC_WAKEUP_BCAST_USERS | TIPC_BCAST_MSG_EVT |

				TIPC_NAMED_MSG_EVT | TIPC_BCAST_RESET);

				TIPC_BCAST_RESET);



	spin_unlock_bh(&node->lock);
@@ -964,12 +955,6 @@ void tipc_node_unlock(struct tipc_node *node) 
		tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,

				      link_id, addr);



	if (flags & TIPC_MSG_EVT)

		tipc_sk_rcv(net, inputq);



	if (flags & TIPC_NAMED_MSG_EVT)

		tipc_named_rcv(net, namedq);



	if (flags & TIPC_BCAST_MSG_EVT)

		tipc_bclink_input(net);
@@ -1270,6 +1255,9 @@ unlock: 
	if (unlikely(rc & TIPC_LINK_DOWN_EVT))

		tipc_node_link_down(n, bearer_id, false);



	if (unlikely(!skb_queue_empty(&n->bclink.namedq)))

		tipc_named_rcv(net, &n->bclink.namedq);



	if (!skb_queue_empty(&le->inputq))

		tipc_sk_rcv(net, &le->inputq);

net/tipc/node.h

+0 −4
Original line number Diff line number Diff line
@@ -53,13 +53,11 @@ 
 * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type

 */

enum {

	TIPC_MSG_EVT                    = 1,

	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),

	TIPC_NOTIFY_NODE_UP		= (1 << 4),

	TIPC_WAKEUP_BCAST_USERS		= (1 << 5),

	TIPC_NOTIFY_LINK_UP		= (1 << 6),

	TIPC_NOTIFY_LINK_DOWN		= (1 << 7),

	TIPC_NAMED_MSG_EVT		= (1 << 8),

	TIPC_BCAST_MSG_EVT		= (1 << 9),

	TIPC_BCAST_RESET		= (1 << 10)

};
@@ -124,8 +122,6 @@ struct tipc_node { 
	spinlock_t lock;

	struct net *net;

	struct hlist_node hash;

	struct sk_buff_head *inputq;

	struct sk_buff_head *namedq;

	int active_links[2];

	struct tipc_link_entry links[MAX_BEARERS];

	int action_flags;

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