Subject: [PATCH 02/28] vxlan: re-ignore EADDRINUSE from igmp_join

From: Marcelo Ricardo Leitner <[email-masked]>
Date: Tue, 25 Aug 2015 20:22:35 -0300

[ Upstream commit bef0057b7ba881d5ae67eec876df7a26fe672a59 ]

Before 56ef9c909b40[1] it used to ignore all errors from igmp_join().
That commit enhanced that and made it error out whatever error happened
with igmp_join(), but that's not good because when using multicast
groups vxlan will try to join it multiple times if the socket is reused
and then the 2nd and further attempts will fail with EADDRINUSE.

As we don't track to which groups the socket is already subscribed, it's
okay to just ignore that error.

Fixes: 56ef9c909b40 ("vxlan: Move socket initialization to within rtnl scope")
Reported-by: John Nielsen <[email-masked]>
Signed-off-by: Marcelo Ricardo Leitner <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 drivers/net/vxlan.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 21a0fbf..0085b8d 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -2212,6 +2212,8 @@ static int vxlan_open(struct net_device *dev)
 
 	if (vxlan_addr_multicast(&vxlan->default_dst.remote_ip)) {
 		ret = vxlan_igmp_join(vxlan);
+		if (ret == -EADDRINUSE)
+			ret = 0;
 		if (ret) {
 			vxlan_sock_release(vs);
 			return ret;
-- 
2.1.0