Re: [PATCH net-next v3 2/8] gtp: switch from struct socket to struct sock for the GTP sockets

From: Andreas Schultz aschultz@tpip.net Date: Wed, 15 Feb 2017 08:04:56 +0100 (CET)

----- On Feb 14, 2017, at 6:48 PM, David S. Miller davem@davemloft.net wrote:

...

From: Andreas Schultz aschultz@tpip.net Date: Mon, 13 Feb 2017 16:36:18 +0100

...

• if (gtp->sk0) {

• udp_sk(gtp->sk0)->encap_type = 0;
  

• rcu_assign_sk_user_data(gtp->sk0, NULL);
  

• sock_put(gtp->sk0);
  

  }

This does "sock_put(NULL);" because you are assigning gtp->sk0 to NULL before the sock_put() call. So you are leaking the socket, at best.

I don't understand how this should happen. If I where to use rcu_assign_pointer, then yes, but rcu_assign_sk_user_data does assign to the sk_user_data member of struct sock and not to the argument itself.

You are right, I misread the assignment.