3.16.85-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Jouni Hogander <jouni.hogan...@unikie.com>

commit ddd9b5e3e765d8ed5a35786a6cb00111713fe161 upstream.

Dev_hold has to be called always in rx_queue_add_kobject.
Otherwise usage count drops below 0 in case of failure in
kobject_init_and_add.

Fixes: b8eb718348b8 ("net-sysfs: Fix reference count leak in 
rx|netdev_queue_add_kobject")
Reported-by: syzbot <syzbot+30209ea299c09d878...@syzkaller.appspotmail.com>
Cc: Tetsuo Handa <penguin-ker...@i-love.sakura.ne.jp>
Cc: David Miller <da...@davemloft.net>
Cc: Lukas Bulwahn <lukas.bulw...@gmail.com>
Signed-off-by: Jouni Hogander <jouni.hogan...@unikie.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
 net/core/net-sysfs.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -782,14 +782,17 @@ static int rx_queue_add_kobject(struct n
        struct kobject *kobj = &queue->kobj;
        int error = 0;
 
+       /* Kobject_put later will trigger rx_queue_release call which
+        * decreases dev refcount: Take that reference here
+        */
+       dev_hold(queue->dev);
+
        kobj->kset = net->queues_kset;
        error = kobject_init_and_add(kobj, &rx_queue_ktype, NULL,
            "rx-%u", index);
        if (error)
                goto err;
 
-       dev_hold(queue->dev);
-
        if (net->sysfs_rx_queue_group) {
                error = sysfs_create_group(kobj, net->sysfs_rx_queue_group);
                if (error)

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