[3.11.y.z extended stable] Patch "rtnetlink: fix fdb notification flags" has been added to staging queue

[Luis Henriques]

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

    rtnetlink: fix fdb notification flags

to the linux-3.11.y-queue branch of the 3.11.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-3.11.y-queue

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

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 6e99fe28d895b017aaa1f70f41578e9850a90aa8 Mon Sep 17 00:00:00 2001
From: Nicolas Dichtel <nicolas.dichtel at 6wind.com>
Date: Wed, 19 Mar 2014 17:47:49 +0100
Subject: rtnetlink: fix fdb notification flags

commit 1c104a6bebf3c16b6248408b84f91d09ac8a26b6 upstream.

Commit 3ff661c38c84 ("net: rtnetlink notify events for FDB NTF_SELF adds and
deletes") reuses the function nlmsg_populate_fdb_fill() to notify fdb 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: Luis Henriques <luis.henriques at canonical.com>
---
 net/core/rtnetlink.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index ca198c1d1..6f73a10 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1991,12 +1991,13 @@ EXPORT_SYMBOL(rtmsg_ifinfo);
 static int nlmsg_populate_fdb_fill(struct sk_buff *skb,
 				   struct net_device *dev,
 				   u8 *addr, u32 pid, u32 seq,
-				   int type, unsigned int flags)
+				   int type, unsigned int flags,
+				   int nlflags)
 {
 	struct nlmsghdr *nlh;
 	struct ndmsg *ndm;

-	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), NLM_F_MULTI);
+	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), nlflags);
 	if (!nlh)
 		return -EMSGSIZE;

@@ -2034,7 +2035,7 @@ static void rtnl_fdb_notify(struct net_device *dev, u8 *addr, int type)
 	if (!skb)
 		goto errout;

-	err = nlmsg_populate_fdb_fill(skb, dev, addr, 0, 0, type, NTF_SELF);
+	err = nlmsg_populate_fdb_fill(skb, dev, addr, 0, 0, type, NTF_SELF, 0);
 	if (err < 0) {
 		kfree_skb(skb);
 		goto errout;
@@ -2259,7 +2260,8 @@ static int nlmsg_populate_fdb(struct sk_buff *skb,

 		err = nlmsg_populate_fdb_fill(skb, dev, ha->addr,
 					      portid, seq,
-					      RTM_NEWNEIGH, NTF_SELF);
+					      RTM_NEWNEIGH, NTF_SELF,
+					      NLM_F_MULTI);
 		if (err < 0)
 			return err;
 skip:
--
1.9.1