Re: [PATCH 1/2] SUNRPC: Don't leak sockets in xs_local_connect()

["wanghai (M)" <wanghai38@huawei.com>]

在 2022/4/28 23:30, trondmy@kernel.org 写道:
> From: Trond Myklebust <trond.myklebust@hammerspace.com>
>
> If there is still a closed socket associated with the transport, then we
> need to trigger an autoclose before we can set up a new connection.
>
> Reported-by: wanghai (M) <wanghai38@huawei.com>
> Fixes: f00432063db1 ("SUNRPC: Ensure we flush any closed sockets before xs_xprt_free()")
> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
> ---
>   net/sunrpc/xprtsock.c | 11 ++++++++++-
>   1 file changed, 10 insertions(+), 1 deletion(-)
Hi, Trond.
Thank you for taking the time to help!

I tested it with this patch and found that the problem still exists.
The path of the sock leak is as follows and is not in xs_local_connect()

write_ports
   nfsd_create_serv
     svc_bind
       rpcb_create_local
         rpcb_create_local_unix
           rpc_create
             xprt_create_transport
               xs_setup_local
                 xs_local_setup_socket
> diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
> index 8ab64ea46870..f9849b297ea3 100644
> --- a/net/sunrpc/xprtsock.c
> +++ b/net/sunrpc/xprtsock.c
> @@ -1950,6 +1950,9 @@ static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
>   	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
>   	int ret;
>   
> +	if (transport->file)
> +		goto force_disconnect;
> +
>   	if (RPC_IS_ASYNC(task)) {
>   		/*
>   		 * We want the AF_LOCAL connect to be resolved in the
> @@ -1962,11 +1965,17 @@ static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
>   		 */
>   		task->tk_rpc_status = -ENOTCONN;
>   		rpc_exit(task, -ENOTCONN);
> -		return;
> +		goto out_wake;
>   	}
>   	ret = xs_local_setup_socket(transport);
>   	if (ret && !RPC_IS_SOFTCONN(task))
>   		msleep_interruptible(15000);
> +	return;
> +force_disconnect:
> +	xprt_force_disconnect(xprt);
> +out_wake:
> +	xprt_clear_connecting(xprt);
> +	xprt_wake_pending_tasks(xprt, -ENOTCONN);
>   }
>   
>   #if IS_ENABLED(CONFIG_SUNRPC_SWAP)

-- 
Wang Hai