1 files changed, 15 insertions, 2 deletions

diff --git a/fs/quota/netlink.c b/fs/quota/netlink.c
index 16e8abb7709b..aa22fe03b76c 100644
--- a/fs/quota/netlink.c
+++ b/fs/quota/netlink.c
@@ -11,13 +11,23 @@
 
 /* Netlink family structure for quota */
 static struct genl_family quota_genl_family = {
-        .id = GENL_ID_GENERATE,
+        /*
+         * Needed due to multicast group ID abuse - old code assumed
+         * the family ID was also a valid multicast group ID (which
+         * isn't true) and userspace might thus rely on it. Assign a
+         * static ID for this group to make dealing with that easier.
+         */
+        .id = GENL_ID_VFS_DQUOT,
         .hdrsize = 0,
         .name = "VFS_DQUOT",
         .version = 1,
         .maxattr = QUOTA_NL_A_MAX,
 };
 
+static struct genl_multicast_group quota_mcgrp = {
+        .name = "events",
+};
+
 /**
  * quota_send_warning - Send warning to userspace about exceeded quota
  * @type: The quota type: USRQQUOTA, GRPQUOTA,...
@@ -78,7 +88,7 @@ void quota_send_warning(struct kqid qid, dev_t dev,
                 goto attr_err_out;
         genlmsg_end(skb, msg_head);
 
-        genlmsg_multicast(skb, 0, quota_genl_family.id, GFP_NOFS);
+        genlmsg_multicast(skb, 0, quota_mcgrp.id, GFP_NOFS);
         return;
 attr_err_out:
         printk(KERN_ERR "VFS: Not enough space to compose quota message!\n");
@@ -92,6 +102,9 @@ static int __init quota_init(void)
         if (genl_register_family(&quota_genl_family) != 0)
                 printk(KERN_ERR
                        "VFS: Failed to create quota netlink interface.\n");
+        if (genl_register_mc_group(&quota_genl_family, &quota_mcgrp))
+                printk(KERN_ERR
+                       "VFS: Failed to register quota mcast group.\n");
         return 0;
 };