From 7c3f362035dec9b7eaec388b1f7f1619c1bd96a3 Mon Sep 17 00:00:00 2001
From: Tony Cook <tony@develop-help.com>
Date: Mon, 4 Nov 2019 09:52:22 +1100
Subject: [PATCH] prevent a race between name-based stat and an open modifying
 atime
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Most linux systems rarely update atime, so it's very unlikely
for this issue to trigger there, but on a system with classic atime
behaviour this was a race between open modifying atime and time()
ticking over.

gh #17234

Signed-off-by: Petr Písař <ppisar@redhat.com>
---
 lib/File/stat.t | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/File/stat.t b/lib/File/stat.t
index c403fc4498..fc9bb12cef 100644
--- a/lib/File/stat.t
+++ b/lib/File/stat.t
@@ -133,6 +133,9 @@ SKIP: {
     test_X_ops($^X, "for $^X", qr/A/);
 }
 
+# open early so atime is consistent with the name based call
+local *STAT;
+my $canopen = open(STAT, '<', $file);
 
 my $stat = File::stat::stat($file);
 isa_ok($stat, 'File::stat', 'should build a stat object');
@@ -143,8 +146,7 @@ for (split //, "tTB") {
 }
 
 SKIP: {
-	local *STAT;
-	skip("Could not open file: $!", 2) unless open(STAT, '<', $file);
+	skip("Could not open file: $!", 2) unless $canopen;
 	isa_ok(File::stat::stat('STAT'), 'File::stat',
 	       '... should be able to find filehandle');
 
-- 
2.21.0