This is a note to let you know that I've just added the patch titled
netlink: ensure to loop over all netns in genlmsg_multicast_allns()
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
netlink-ensure-to-loop-over-all-netns-in-genlmsg_multicast_allns.patch
and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Thu Mar 8 10:42:32 PST 2018
From: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
Date: Tue, 6 Feb 2018 14:48:32 +0100
Subject: netlink: ensure to loop over all netns in genlmsg_multicast_allns()
From: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
[ Upstream commit cb9f7a9a5c96a773bbc9c70660dc600cfff82f82 ]
Nowadays, nlmsg_multicast() returns only 0 or -ESRCH but this was not the
case when commit 134e63756d5f was pushed.
However, there was no reason to stop the loop if a netns does not have
listeners.
Returns -ESRCH only if there was no listeners in all netns.
To avoid having the same problem in the future, I didn't take the
assumption that nlmsg_multicast() returns only 0 or -ESRCH.
Fixes: 134e63756d5f ("genetlink: make netns aware")
CC: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netlink/genetlink.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -1058,6 +1058,7 @@ static int genlmsg_mcast(struct sk_buff
{
struct sk_buff *tmp;
struct net *net, *prev = NULL;
+ bool delivered = false;
int err;
for_each_net_rcu(net) {
@@ -1069,14 +1070,21 @@ static int genlmsg_mcast(struct sk_buff
}
err = nlmsg_multicast(prev->genl_sock, tmp,
portid, group, flags);
- if (err)
+ if (!err)
+ delivered = true;
+ else if (err != -ESRCH)
goto error;
}
prev = net;
}
- return nlmsg_multicast(prev->genl_sock, skb, portid, group, flags);
+ err = nlmsg_multicast(prev->genl_sock, skb, portid, group, flags);
+ if (!err)
+ delivered = true;
+ else if (err != -ESRCH)
+ goto error;
+ return delivered ? 0 : -ESRCH;
error:
kfree_skb(skb);
return err;
Patches currently in stable-queue which might be from nicolas.dichtel@xxxxxxxxx are
queue-3.18/netlink-ensure-to-loop-over-all-netns-in-genlmsg_multicast_allns.patch