From 117ddd9dd093aefa839899a452a4ae52cea18b4d Mon Sep 17 00:00:00 2001
From: Ken Brown <kbrown@cornell.edu>
Date: Tue, 23 Feb 2021 17:07:00 -0500
Subject: [PATCH] Cygwin: facl: fail with EBADF on files opened with O_PATH

This is in the spirit of the Linux requirement that file operations
like fchmod(2), fchown(2), and fgetxattr(2) fail with EBADF on files
opened with O_PATH.
---
 winsup/cygwin/sec_acl.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/winsup/cygwin/sec_acl.cc b/winsup/cygwin/sec_acl.cc
index fe015728d..90969b639 100644
--- a/winsup/cygwin/sec_acl.cc
+++ b/winsup/cygwin/sec_acl.cc
@@ -1246,6 +1246,11 @@ facl32 (int fd, int cmd, int nentries, aclent_t *aclbufp)
       syscall_printf ("-1 = facl (%d)", fd);
       return -1;
     }
+  if (cfd->get_flags () & O_PATH)
+    {
+      set_errno (EBADF);
+      return -1;
+    }
   int res = cfd->facl (cmd, nentries, aclbufp);
   syscall_printf ("%R = facl(%s) )", res, cfd->get_name ());
   return res;