[PATCH] WAN: protect HDLC proto list while insmod/rmmod

Krzysztof Halasa
2008-05-19T17:00:53Z

WAN: protect protocol list in hdlc.c with RTNL.

Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>

--- a/drivers/net/wan/hdlc.c
+++ b/drivers/net/wan/hdlc.c
@@ -42,8 +42,7 @@ static const char* version = "HDLC support module revision 1.22";

#undef DEBUG_LINK

-static struct hdlc_proto *first_proto = NULL;
-
+static struct hdlc_proto *first_proto;

static int hdlc_change_mtu(struct net_device *dev, int new_mtu)
{
@@ -313,21 +312,25 @@ void detach_hdlc_protocol(struct net_device *dev)

void register_hdlc_protocol(struct hdlc_proto *proto)
{
+ rtnl_lock();
proto->next = first_proto;
first_proto = proto;
+ rtnl_unlock();
}

void unregister_hdlc_protocol(struct hdlc_proto *proto)
{
- struct hdlc_proto **p = &first_proto;
- while (*p) {
- if (*p == proto) {
- *p = proto->next;
- return;
- }
+ struct hdlc_proto **p;
+
+ rtnl_lock();
+ p = &first_proto;
+ while (*p != proto) {
+ BUG_ON(!*p);
p = &((*p)->next);
}
+ *p = proto->next;
+ rtnl_unlock();
}