Subject: [PATCH] [ROSE] proper test for routing frames in rose_get_neigh()

From: Bernard Pidoux <[email-masked]>
Date: Wed, 14 May 2008 20:14:29 +0200

rose_get_neigh() is called either by rose_connect() or by rose_route_frame().
In the first case it checks f0 timer to find if a connection is in wait state.
In that case it returns a NULL otherwise it returns the address
of the neighbour.

When called by rose_route_frame() the idea was to route a packet through an
adjacent node given a destination rose address.
However in that case t0 timer does not tell if the adjacent node is
already connected even if the timer is null.

A second conditional loop is added to check rose_neigh "restarted" structure
field for this is the one that is set when a neighbour is connected.
When the argument 'new' is null the function knows it is called by
rose_route frame. If an adjacent node routing the requested route address is
already connected, rose_get_neigh() returns its address, otherwise it returns
a NULL. In that case the calling function will initiate a new connection.

Signed-off-by: Bernard Pidoux <[email-masked]>
---
 include/net/rose.h    |    2 +-
 net/rose/af_rose.c    |    4 ++--
 net/rose/rose_route.c |   29 ++++++++++++++++++-----------
 3 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/include/net/rose.h b/include/net/rose.h
index e5bb084..cbd5364 100644
--- a/include/net/rose.h
+++ b/include/net/rose.h
@@ -201,7 +201,7 @@ extern void rose_link_device_down(struct net_device *);
 extern struct net_device *rose_dev_first(void);
 extern struct net_device *rose_dev_get(rose_address *);
 extern struct rose_route *rose_route_free_lci(unsigned int, struct rose_neigh *);
-extern struct rose_neigh *rose_get_neigh(rose_address *, unsigned char *, unsigned char *);
+extern struct rose_neigh *rose_get_neigh(rose_address *, unsigned char *, unsigned char *, int);
 extern int  rose_rt_ioctl(unsigned int, void __user *);
 extern void rose_link_failed(ax25_cb *, int);
 extern int  rose_route_frame(struct sk_buff *, ax25_cb *);
diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c
index 1ebf652..f7f7ec8 100644
--- a/net/rose/af_rose.c
+++ b/net/rose/af_rose.c
@@ -759,7 +759,7 @@ static int rose_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le
 	sock->state = SS_UNCONNECTED;
 
 	rose->neighbour = rose_get_neigh(&addr->srose_addr, &cause,
-					 &diagnostic);
+					 &diagnostic, 0);
 	if (!rose->neighbour) {
 		err = -ENETUNREACH;
 		goto out_release;
@@ -855,7 +855,7 @@ rose_try_next_neigh:
 
 	if (sk->sk_state != TCP_ESTABLISHED) {
 	/* Try next neighbour */
-		rose->neighbour = rose_get_neigh(&addr->srose_addr, &cause, &diagnostic);
+		rose->neighbour = rose_get_neigh(&addr->srose_addr, &cause, &diagnostic, 0);
 		if (rose->neighbour)
 			goto rose_try_next_neigh;
 
diff --git a/net/rose/rose_route.c b/net/rose/rose_route.c
index bd59387..a81066a 100644
--- a/net/rose/rose_route.c
+++ b/net/rose/rose_route.c
@@ -662,27 +662,34 @@ struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neig
 }
 
 /*
- *	Find a neighbour given a ROSE address.
+ *	Find a neighbour or a route given a ROSE address.
  */
 struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
-	unsigned char *diagnostic)
+	unsigned char *diagnostic, int new)
 {
 	struct rose_neigh *res = NULL;
 	struct rose_node *node;
 	int failed = 0;
 	int i;
 
-	spin_lock_bh(&rose_node_list_lock);
+	if (!new) spin_lock_bh(&rose_node_list_lock);
 	for (node = rose_node_list; node != NULL; node = node->next) {
 		if (rosecmpm(addr, &node->address, node->mask) == 0) {
 			for (i = 0; i < node->count; i++) {
-				if (!rose_ftimer_running(node->neighbour[i])) {
-					res = node->neighbour[i];
-					goto out;
-				} else
-					failed = 1;
+				if (new) {
+					if (node->neighbour[i]->restarted) {
+						res = node->neighbour[i];
+						goto out;
+					}
+				}
+				else {
+					if (!rose_ftimer_running(node->neighbour[i])) {
+						res = node->neighbour[i];
+						goto out;
+					} else
+						failed = 1;
+				}
 			}
-			break;
 		}
 	}
 
@@ -695,7 +702,7 @@ struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
 	}
 
 out:
-	spin_unlock_bh(&rose_node_list_lock);
+	if (!new) spin_unlock_bh(&rose_node_list_lock);
 
 	return res;
 }
@@ -1018,7 +1025,7 @@ int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
 		rose_route = rose_route->next;
 	}
 
-	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic)) == NULL) {
+	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
 		rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
 		goto out;
 	}
-- 
1.5.5