ipmr: fix mfc notification flags

Commit 8cd3ac9f9b7b ("ipmr: advertise new mfc entries via rtnl") reuses the
function ipmr_fill_mroute() to notify mfc events.
But this function was used only for dump and thus was always setting the
flag NLM_F_MULTI, which is wrong in case of a single notification.

Libraries like libnl will wait forever for NLMSG_DONE.

CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 5 deletions

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index b9b3472975ba..28863570dd60 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -2255,13 +2255,14 @@ int ipmr_get_route(struct net *net, struct sk_buff *skb,
 }
 
 static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
-                            u32 portid, u32 seq, struct mfc_cache *c, int cmd)
+                            u32 portid, u32 seq, struct mfc_cache *c, int cmd,
+                            int flags)
 {
         struct nlmsghdr *nlh;
         struct rtmsg *rtm;
         int err;
 
-        nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), NLM_F_MULTI);
+        nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
         if (nlh == NULL)
                 return -EMSGSIZE;
 
@@ -2329,7 +2330,7 @@ static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
         if (skb == NULL)
                 goto errout;
 
-        err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd);
+        err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
         if (err < 0)
                 goto errout;
 
@@ -2368,7 +2369,8 @@ static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
                                 if (ipmr_fill_mroute(mrt, skb,
                                                      NETLINK_CB(cb->skb).portid,
                                                      cb->nlh->nlmsg_seq,
-                                                     mfc, RTM_NEWROUTE) < 0)
+                                                     mfc, RTM_NEWROUTE,
+                                                     NLM_F_MULTI) < 0)
                                         goto done;
 next_entry:
                                 e++;
@@ -2382,7 +2384,8 @@ next_entry:
                         if (ipmr_fill_mroute(mrt, skb,
                                              NETLINK_CB(cb->skb).portid,
                                              cb->nlh->nlmsg_seq,
-                                             mfc, RTM_NEWROUTE) < 0) {
+                                             mfc, RTM_NEWROUTE,
+                                             NLM_F_MULTI) < 0) {
                                 spin_unlock_bh(&mfc_unres_lock);
                                 goto done;
                         }