commit fa701bd24d6e64a2283d6fa386554775fd4336e7
author Krzysztof Halasa <khc@pm.waw.pl> Mon May 19 19:00:51 2008 +0200
committer Jeff Garzik <jgarzik@redhat.com> Thu May 22 06:26:32 2008 -0400
tree 980f65214d2abc363b30762d6fac7b569805af47
parent 4ecc8c066f3cecb55807644a01435084d8ed638a

WAN: protect HDLC proto list while insmod/rmmod

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

Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/net/wan/hdlc.c

diff --git a/drivers/net/wan/hdlc.c b/drivers/net/wan/hdlc.c
index 9a83c9d..7f98489 100644
--- a/drivers/net/wan/hdlc.c
+++ b/drivers/net/wan/hdlc.c
@@ -43,8 +43,7 @@
 
 #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)
 {
@@ -314,21 +313,25 @@
 
 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();
 }