1 files changed, 49 insertions, 0 deletions

diff --git a/net/bridge/br_sysfs_br.c b/net/bridge/br_sysfs_br.c
index 6f577f16c4c0..96bcb2ff59ab 100644
--- a/net/bridge/br_sysfs_br.c
+++ b/net/bridge/br_sysfs_br.c
@@ -242,6 +242,54 @@ static ssize_t show_gc_timer(struct class_device *cd, char *buf)
 }
 static CLASS_DEVICE_ATTR(gc_timer, S_IRUGO, show_gc_timer, NULL);
 
+static ssize_t show_group_addr(struct class_device *cd, char *buf)
+{
+        struct net_bridge *br = to_bridge(cd);
+        return sprintf(buf, "%x:%x:%x:%x:%x:%x\n",
+                       br->group_addr[0], br->group_addr[1],
+                       br->group_addr[2], br->group_addr[3],
+                       br->group_addr[4], br->group_addr[5]);
+}
+
+static ssize_t store_group_addr(struct class_device *cd, const char *buf,
+                                    size_t len)
+{
+        struct net_bridge *br = to_bridge(cd);
+        unsigned new_addr[6];
+        int i;
+
+        if (!capable(CAP_NET_ADMIN))
+                return -EPERM;
+
+        if (sscanf(buf, "%x:%x:%x:%x:%x:%x",
+                   &new_addr[0], &new_addr[1], &new_addr[2],
+                   &new_addr[3], &new_addr[4], &new_addr[5]) != 6)
+                return -EINVAL;
+
+        /* Must be 01:80:c2:00:00:0X */
+        for (i = 0; i < 5; i++)
+                if (new_addr[i] != br_group_address[i])
+                        return -EINVAL;
+
+        if (new_addr[5] & ~0xf)
+                return -EINVAL;
+
+        if (new_addr[5] == 1    /* 802.3x Pause address */
+            || new_addr[5] == 2 /* 802.3ad Slow protocols */
+            || new_addr[5] == 3) /* 802.1X PAE address */
+                return -EINVAL;
+
+        spin_lock_bh(&br->lock);
+        for (i = 0; i < 6; i++)
+                br->group_addr[i] = new_addr[i];
+        spin_unlock_bh(&br->lock);
+        return len;
+}
+
+static CLASS_DEVICE_ATTR(group_addr, S_IRUGO | S_IWUSR,
+                         show_group_addr, store_group_addr);
+
+
 static struct attribute *bridge_attrs[] = {
         &class_device_attr_forward_delay.attr,
         &class_device_attr_hello_time.attr,
@@ -259,6 +307,7 @@ static struct attribute *bridge_attrs[] = {
         &class_device_attr_tcn_timer.attr,
         &class_device_attr_topology_change_timer.attr,
         &class_device_attr_gc_timer.attr,
+        &class_device_attr_group_addr.attr,
         NULL
 };