From 40b532fbdcb2095da7152a1d08d9f0288524c223 Mon Sep 17 00:00:00 2001
From: Jason Andryuk <jandryuk@gmail.com>
Date: Wed, 10 Jun 2020 23:29:36 -0400
Subject: [PATCH] vchan-socket-proxy: Handle closing shared input/output_fd
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input_fd & output_fd may be the same FD.  In that case, mark both as -1
when closing one.  That avoids a dangling FD reference.

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: Wei Liu <wl@xen.org>
Reviewed-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Release-acked-by: Paul Durrant <paul@xen.org>
---
 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 3552783ec2..e1d959c6d1 100644
--- a/tools/libvchan/vchan-socket-proxy.c
+++ b/tools/libvchan/vchan-socket-proxy.c
@@ -349,6 +349,8 @@ int data_loop(struct vchan_proxy_state *state)
                     libxenvchan_wait(state->ctrl);
                 }
                 close(state->input_fd);
+                if (state->input_fd == state->output_fd)
+                    state->output_fd = -1;
                 state->input_fd = -1;
                 /* TODO: maybe signal the vchan client somehow? */
                 break;
-- 
2.39.5