channel: Do not return error if the server closed the channel

If the server properly closed the channel, the client should not return
error if it finds the channel closed.

Fixes T231

Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>

src/channels.c

@@ -2932,15 +2932,16 @@ int ssh_channel_read_timeout(ssh_channel channel,
   if (session->session_state == SSH_SESSION_STATE_ERROR) {
       return SSH_ERROR;
   }
+  /* If the server closed the channel properly, there is nothing to do */
+  if (channel->remote_eof && ssh_buffer_get_len(stdbuf) == 0) {
+      return 0;
+  }
   if (channel->state == SSH_CHANNEL_STATE_CLOSED) {
       ssh_set_error(session,
                     SSH_FATAL,
                     "Remote channel is closed.");
       return SSH_ERROR;
   }
-  if (channel->remote_eof && ssh_buffer_get_len(stdbuf) == 0) {
-    return 0;
-  }
   len = ssh_buffer_get_len(stdbuf);
   /* Read count bytes if len is greater, everything otherwise */
   len = (len > count ? count : len);