net: sock_bindtodevice() RCU-ification

Avoid dev_hold()/dev_put() in sock_bindtodevice()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 4 deletions

diff --git a/net/core/sock.c b/net/core/sock.c
index 5a51512f638a..38820eaecd43 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -420,14 +420,16 @@ static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
         if (devname[0] == '\0') {
                 index = 0;
         } else {
-                struct net_device *dev = dev_get_by_name(net, devname);
+                struct net_device *dev;
 
+                rcu_read_lock();
+                dev = dev_get_by_name_rcu(net, devname);
+                if (dev)
+                        index = dev->ifindex;
+                rcu_read_unlock();
                 ret = -ENODEV;
                 if (!dev)
                         goto out;
-
-                index = dev->ifindex;
-                dev_put(dev);
         }
 
         lock_sock(sk);