net/packet: fix missing net_device reference release

When using a TX ring buffer, if an error occurs processing a control
message (e.g. invalid message), the net_device reference is not
released.

Fixes c14ac9451c348 ("sock: enable timestamping using control messages")
Signed-off-by: Douglas Caetano dos Santos <douglascs@taghos.com.br>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 7 deletions

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index f4001763134d..e3eeed19cc7a 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -2658,13 +2658,6 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
                 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
         }
 
-        sockc.tsflags = po->sk.sk_tsflags;
-        if (msg->msg_controllen) {
-                err = sock_cmsg_send(&po->sk, msg, &sockc);
-                if (unlikely(err))
-                        goto out;
-        }
-
         err = -ENXIO;
         if (unlikely(dev == NULL))
                 goto out;
@@ -2672,6 +2665,13 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
         if (unlikely(!(dev->flags & IFF_UP)))
                 goto out_put;
 
+        sockc.tsflags = po->sk.sk_tsflags;
+        if (msg->msg_controllen) {
+                err = sock_cmsg_send(&po->sk, msg, &sockc);
+                if (unlikely(err))
+                        goto out_put;
+        }
+
         if (po->sk.sk_socket->type == SOCK_RAW)
                 reserve = dev->hard_header_len;
         size_max = po->tx_ring.frame_size