[PATCH net-next] tcp: allow to enable the repair mode for non-listening sockets

[PATCH net-next] tcp: allow to enable the repair mode for non-listening sockets

[Andrei Vagin]

The repair mode is used to get and restore sequence numbers and
data from queues. It used to checkpoint/restore connections.

Currently the repair mode can be enabled for sockets in the established
and closed states, but for other states we have to dump the same socket
properties, so lets allow to enable repair mode for these sockets.

The repair mode reveals nothing more for sockets in other states.

Signed-off-by: Andrei Vagin <avagin@openvz.org>
---
 net/ipv4/tcp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 3251fe7..a2a3a8c 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2302,7 +2302,7 @@ EXPORT_SYMBOL(tcp_disconnect);
 static inline bool tcp_can_repair_sock(const struct sock *sk)
 {
 	return ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN) &&
-		((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_ESTABLISHED));
+		(sk->sk_state != TCP_LISTEN);
 }
 
 static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int len)
-- 
2.7.4

Re: [CRIU] [PATCH net-next] tcp: allow to enable the repair mode for non-listening sockets

[Pavel Emelyanov]

On 11/15/2016 05:15 AM, Andrei Vagin wrote:
> The repair mode is used to get and restore sequence numbers and
> data from queues. It used to checkpoint/restore connections.
> 
> Currently the repair mode can be enabled for sockets in the established
> and closed states, but for other states we have to dump the same socket
> properties, so lets allow to enable repair mode for these sockets.
> 
> The repair mode reveals nothing more for sockets in other states.
> 
> Signed-off-by: Andrei Vagin <avagin@openvz.org>

Acked-by: Pavel Emelyanov <xemul@openvz.org>

> ---
>  net/ipv4/tcp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
> index 3251fe7..a2a3a8c 100644
> --- a/net/ipv4/tcp.c
> +++ b/net/ipv4/tcp.c
> @@ -2302,7 +2302,7 @@ EXPORT_SYMBOL(tcp_disconnect);
>  static inline bool tcp_can_repair_sock(const struct sock *sk)
>  {
>  	return ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN) &&
> -		((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_ESTABLISHED));
> +		(sk->sk_state != TCP_LISTEN);
>  }
>  
>  static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int len)
> 

Re: [PATCH net-next] tcp: allow to enable the repair mode for non-listening sockets

[David Miller]

From: Andrei Vagin <avagin@openvz.org>
Date: Mon, 14 Nov 2016 18:15:14 -0800

> The repair mode is used to get and restore sequence numbers and
> data from queues. It used to checkpoint/restore connections.
> 
> Currently the repair mode can be enabled for sockets in the established
> and closed states, but for other states we have to dump the same socket
> properties, so lets allow to enable repair mode for these sockets.
> 
> The repair mode reveals nothing more for sockets in other states.
> 
> Signed-off-by: Andrei Vagin <avagin@openvz.org>

Applied.