From 4bacd01a8e1fa1909d5f1c85ebc39fa462b5c022 Mon Sep 17 00:00:00 2001
From: Tim Zhang <tim@hyper.sh>
Date: Tue, 25 May 2021 11:40:54 +0800
Subject: [PATCH] Set FD_CLOEXEC for duped epoll_fd

The close-on-exec flag (FD_CLOEXEC; see fcntl(2)) for the duplicate descriptor is off
and we should set it manually.

Fixes: tokio-rs/tokio#3809

Signed-off-by: Tim Zhang <tim@hyper.sh>
---
 src/sys/unix/selector/epoll.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/sys/unix/selector/epoll.rs b/src/sys/unix/selector/epoll.rs
index 76ee7f91a..997a54b12 100644
--- a/src/sys/unix/selector/epoll.rs
+++ b/src/sys/unix/selector/epoll.rs
@@ -41,7 +41,7 @@ impl Selector {
     }
 
     pub fn try_clone(&self) -> io::Result<Selector> {
-        syscall!(dup(self.ep)).map(|ep| Selector {
+        syscall!(fcntl(self.ep, libc::F_DUPFD_CLOEXEC)).map(|ep| Selector {
             // It's the same selector, so we use the same id.
             #[cfg(debug_assertions)]
             id: self.id,