[3.8.y.z extended stable] Patch "ipmr: fix mfc notification flags" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    ipmr: fix mfc notification flags

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.22.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 3106a51108cf680393f9fe6f3c7fb2912812a97f Mon Sep 17 00:00:00 2001
From: Nicolas Dichtel <nicolas.dichtel at 6wind.com>
Date: Wed, 19 Mar 2014 17:47:50 +0100
Subject: ipmr: fix mfc notification flags

[ Upstream commit 65886f439ab0fdc2dff20d1fa87afb98c6717472 ]

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 at suug.ch>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel at 6wind.com>
Acked-by: Thomas Graf <tgraf at suug.ch>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/ipv4/ipmr.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 5bb4619..1b3b2b4 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -2161,13 +2161,14 @@ 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;

@@ -2235,7 +2236,7 @@ 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;

@@ -2274,7 +2275,8 @@ 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++;
@@ -2288,7 +2290,8 @@ 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;
 			}
--
1.8.3.2