ax25: netrom: rose: Fix timer oopses
Wrong ax25_cb refcounting in ax25_send_frame() and by its callers can
cause timer oopses (first reported with 2.6.29.6 kernel).
Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=14905
Reported-by: Bernard Pidoux <bpidoux@free.fr>
Tested-by: Bernard Pidoux <bpidoux@free.fr>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/netrom.h b/include/net/netrom.h
index 15696b1..ab170a6 100644
--- a/include/net/netrom.h
+++ b/include/net/netrom.h
@@ -132,6 +132,8 @@
static __inline__ void nr_neigh_put(struct nr_neigh *nr_neigh)
{
if (atomic_dec_and_test(&nr_neigh->refcount)) {
+ if (nr_neigh->ax25)
+ ax25_cb_put(nr_neigh->ax25);
kfree(nr_neigh->digipeat);
kfree(nr_neigh);
}
diff --git a/net/ax25/ax25_out.c b/net/ax25/ax25_out.c
index bf706f8..1491260 100644
--- a/net/ax25/ax25_out.c
+++ b/net/ax25/ax25_out.c
@@ -92,6 +92,12 @@
#endif
}
+ /*
+ * There is one ref for the state machine; a caller needs
+ * one more to put it back, just like with the existing one.
+ */
+ ax25_cb_hold(ax25);
+
ax25_cb_add(ax25);
ax25->state = AX25_STATE_1;
diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c
index aacba76..e2e2d33 100644
--- a/net/netrom/nr_route.c
+++ b/net/netrom/nr_route.c
@@ -843,12 +843,13 @@
dptr = skb_push(skb, 1);
*dptr = AX25_P_NETROM;
- ax25s = ax25_send_frame(skb, 256, (ax25_address *)dev->dev_addr, &nr_neigh->callsign, nr_neigh->digipeat, nr_neigh->dev);
- if (nr_neigh->ax25 && ax25s) {
- /* We were already holding this ax25_cb */
+ ax25s = nr_neigh->ax25;
+ nr_neigh->ax25 = ax25_send_frame(skb, 256,
+ (ax25_address *)dev->dev_addr,
+ &nr_neigh->callsign,
+ nr_neigh->digipeat, nr_neigh->dev);
+ if (ax25s)
ax25_cb_put(ax25s);
- }
- nr_neigh->ax25 = ax25s;
dev_put(dev);
ret = (nr_neigh->ax25 != NULL);
diff --git a/net/rose/rose_link.c b/net/rose/rose_link.c
index bd86a63..5ef5f69 100644
--- a/net/rose/rose_link.c
+++ b/net/rose/rose_link.c
@@ -101,13 +101,17 @@
static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh)
{
ax25_address *rose_call;
+ ax25_cb *ax25s;
if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
rose_call = (ax25_address *)neigh->dev->dev_addr;
else
rose_call = &rose_callsign;
+ ax25s = neigh->ax25;
neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
+ if (ax25s)
+ ax25_cb_put(ax25s);
return (neigh->ax25 != NULL);
}
@@ -120,13 +124,17 @@
static int rose_link_up(struct rose_neigh *neigh)
{
ax25_address *rose_call;
+ ax25_cb *ax25s;
if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
rose_call = (ax25_address *)neigh->dev->dev_addr;
else
rose_call = &rose_callsign;
+ ax25s = neigh->ax25;
neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
+ if (ax25s)
+ ax25_cb_put(ax25s);
return (neigh->ax25 != NULL);
}
diff --git a/net/rose/rose_route.c b/net/rose/rose_route.c
index 795c4b0..70a0b3b 100644
--- a/net/rose/rose_route.c
+++ b/net/rose/rose_route.c
@@ -235,6 +235,8 @@
if ((s = rose_neigh_list) == rose_neigh) {
rose_neigh_list = rose_neigh->next;
+ if (rose_neigh->ax25)
+ ax25_cb_put(rose_neigh->ax25);
kfree(rose_neigh->digipeat);
kfree(rose_neigh);
return;
@@ -243,6 +245,8 @@
while (s != NULL && s->next != NULL) {
if (s->next == rose_neigh) {
s->next = rose_neigh->next;
+ if (rose_neigh->ax25)
+ ax25_cb_put(rose_neigh->ax25);
kfree(rose_neigh->digipeat);
kfree(rose_neigh);
return;
@@ -812,6 +816,7 @@
if (rose_neigh != NULL) {
rose_neigh->ax25 = NULL;
+ ax25_cb_put(ax25);
rose_del_route_by_neigh(rose_neigh);
rose_kill_by_neigh(rose_neigh);