These FDs are closed, so set them to -1 so they are no longer valid.

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
---
 tools/libvchan/vchan-socket-proxy.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/libvchan/vchan-socket-proxy.c b/tools/libvchan/vchan-socket-proxy.c
index 29a12260ed..cd7629bc4e 100644
--- a/tools/libvchan/vchan-socket-proxy.c
+++ b/tools/libvchan/vchan-socket-proxy.c
@@ -326,7 +326,9 @@ int data_loop(struct vchan_proxy_state *state)
                 while (outsiz)
                     socket_wr(state->output_fd);
                 close(state->output_fd);
+                state->output_fd = -1;
                 close(state->input_fd);
+                state->input_fd = -1;
                 discard_buffers(state->ctrl);
                 break;
             }
-- 
2.25.1