Merge branch 'genetlink_mcast'

Johannes Berg says:

====================
genetlink: clean up multicast group APIs

The generic netlink multicast group registration doesn't have to
be dynamic, and can thus be simplified just like I did with the
ops. This removes some complexity in registration code.

Additionally, two users of generic netlink already use multicast
groups in a wrong way, add workarounds for those two to keep the
userspace API working, but at the same time make them not clash
with other users of multicast groups as might happen now.

While making it all a bit easier, also prevent such abuse by adding
checks to the APIs so each family can only use the groups it owns.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 16 deletions

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 4962a6a..19edd61 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -1606,15 +1606,17 @@ exit:
 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
 
 #ifdef CONFIG_NET
+static const struct genl_multicast_group thermal_event_mcgrps[] = {
+	{ .name = THERMAL_GENL_MCAST_GROUP_NAME, },
+};
+
 static struct genl_family thermal_event_genl_family = {
 	.id = GENL_ID_GENERATE,
 	.name = THERMAL_GENL_FAMILY_NAME,
 	.version = THERMAL_GENL_VERSION,
 	.maxattr = THERMAL_GENL_ATTR_MAX,
-};
-
-static struct genl_multicast_group thermal_event_mcgrp = {
-	.name = THERMAL_GENL_MCAST_GROUP_NAME,
+	.mcgrps = thermal_event_mcgrps,
+	.n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
 };
 
 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
@@ -1675,7 +1677,8 @@ int thermal_generate_netlink_event(struct thermal_zone_device *tz,
 		return result;
 	}
 
-	result = genlmsg_multicast(skb, 0, thermal_event_mcgrp.id, GFP_ATOMIC);
+	result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
+				   0, GFP_ATOMIC);
 	if (result)
 		dev_err(&tz->device, "Failed to send netlink event:%d", result);
 
@@ -1685,17 +1688,7 @@ EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
 
 static int genetlink_init(void)
 {
-	int result;
-
-	result = genl_register_family(&thermal_event_genl_family);
-	if (result)
-		return result;
-
-	result = genl_register_mc_group(&thermal_event_genl_family,
-					&thermal_event_mcgrp);
-	if (result)
-		genl_unregister_family(&thermal_event_genl_family);
-	return result;
+	return genl_register_family(&thermal_event_genl_family);
 }
 
 static void genetlink_exit(void)