Merge branch 'net-subsystem-misc-refcounter-conversions'

Elena Reshetova says:

====================
v2 net subsystem misc refcounter conversions

Changes in v2:
 * rebase on top of net-next
 * currently by default refcount_t = atomic_t (*) and uses all
   atomic standard operations unless CONFIG_REFCOUNT_FULL is enabled.
   This is a compromise for the systems that are critical on
   performance (such as net) and cannot accept even slight delay
   on the refcounter operations.

This series, for various misc network components, replaces atomic_t reference
counters with the new refcount_t type and API (see include/linux/refcount.h).
By doing this we prevent intentional or accidental
underflows or overflows that can led to use-after-free vulnerabilities.
These are the last networking-related conversions with the exception of
network drivers (to be send separately).

Please excuse the long patch set, but seems like breaking it up
won't save that much on CC list and most of the changes are
trivial.

The patches are fully independent and can be cherry-picked separately.
In order to try with refcount functionality enabled in run-time,
CONFIG_REFCOUNT_FULL must be enabled.

NOTE: automatic kernel builder for some reason doesn't like all my
network branches and regularly times out the builds on these branches.
Suggestion for "waiting a day for a good coverage" doesn't work, as
we have seen with generic network conversions. So please wait for the
full report from kernel test rebot before merging further up.
This has been compile-tested in 116 configs, but 71 timed out (including
all s390-related configs again). I am trying to see if they can fix
build coverage for me in meanwhile.

* The respective change is currently merged into -next as
  "locking/refcount: Create unchecked atomic_t implementation".
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 5 insertions, 5 deletions

diff --git a/net/ipx/af_ipx.c b/net/ipx/af_ipx.c
index fa31ef29e3fa..ac598ec90589 100644
--- a/net/ipx/af_ipx.c
+++ b/net/ipx/af_ipx.c
@@ -308,7 +308,7 @@ void ipxitf_down(struct ipx_interface *intrfc)
 
 static void __ipxitf_put(struct ipx_interface *intrfc)
 {
-	if (atomic_dec_and_test(&intrfc->refcnt))
+	if (refcount_dec_and_test(&intrfc->refcnt))
 		__ipxitf_down(intrfc);
 }
 
@@ -876,7 +876,7 @@ static struct ipx_interface *ipxitf_alloc(struct net_device *dev, __be32 netnum,
 		intrfc->if_ipx_offset 	= ipx_offset;
 		intrfc->if_sknum 	= IPX_MIN_EPHEMERAL_SOCKET;
 		INIT_HLIST_HEAD(&intrfc->if_sklist);
-		atomic_set(&intrfc->refcnt, 1);
+		refcount_set(&intrfc->refcnt, 1);
 		spin_lock_init(&intrfc->if_sklist_lock);
 	}
 
@@ -1105,7 +1105,7 @@ static struct ipx_interface *ipxitf_auto_create(struct net_device *dev,
 		memcpy((char *)&(intrfc->if_node[IPX_NODE_LEN-dev->addr_len]),
 			dev->dev_addr, dev->addr_len);
 		spin_lock_init(&intrfc->if_sklist_lock);
-		atomic_set(&intrfc->refcnt, 1);
+		refcount_set(&intrfc->refcnt, 1);
 		ipxitf_insert(intrfc);
 		dev_hold(dev);
 	}
diff --git a/net/ipx/ipx_proc.c b/net/ipx/ipx_proc.c
index c1d247ebe916..7d75e4c5c75d 100644
--- a/net/ipx/ipx_proc.c
+++ b/net/ipx/ipx_proc.c
@@ -53,7 +53,7 @@ static int ipx_seq_interface_show(struct seq_file *seq, void *v)
 	seq_printf(seq, "%-11s", ipx_device_name(i));
 	seq_printf(seq, "%-9s", ipx_frame_name(i->if_dlink_type));
 #ifdef IPX_REFCNT_DEBUG
-	seq_printf(seq, "%6d", atomic_read(&i->refcnt));
+	seq_printf(seq, "%6d", refcount_read(&i->refcnt));
 #endif
 	seq_puts(seq, "\n");
 out:
diff --git a/net/ipx/ipx_route.c b/net/ipx/ipx_route.c
index 3e2a32a9f3bd..b5d91447f3dc 100644
--- a/net/ipx/ipx_route.c
+++ b/net/ipx/ipx_route.c
@@ -59,7 +59,7 @@ int ipxrtr_add_route(__be32 network, struct ipx_interface *intrfc,
 		if (!rt)
 			goto out;
 
-		atomic_set(&rt->refcnt, 1);
+		refcount_set(&rt->refcnt, 1);
 		ipxrtr_hold(rt);
 		write_lock_bh(&ipx_routes_lock);
 		list_add(&rt->node, &ipx_routes);