From f813e9f937b5b6198659c8c64b3090dc3902b930 Mon Sep 17 00:00:00 2001
From: Simon Tatham <anakin@pobox.com>
Date: Sun, 1 Oct 2017 21:05:25 +0100
Subject: [PATCH] uxnet.c: don't close a socket's fd if it is -1.

This is harmless in principle (you just get EBADF back from close(2)
and ignore it), but it leads to warnings in valgrind.
---
 unix/uxnet.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/unix/uxnet.c b/unix/uxnet.c
index ddcd9228..f3498527 100644
--- a/unix/uxnet.c
+++ b/unix/uxnet.c
@@ -1023,9 +1023,11 @@ static void sk_tcp_close(Socket sock)
     if (s->child)
         sk_tcp_close((Socket)s->child);
 
-    uxsel_del(s->s);
     del234(sktree, s);
-    close(s->s);
+    if (s->s >= 0) {
+        uxsel_del(s->s);
+        close(s->s);
+    }
     if (s->addr)
         sk_addr_free(s->addr);
     sfree(s);