[newlib-cygwin] Cygwin: unlink: filter out virtual files and devices early on

[newlib-cygwin] Cygwin: unlink: filter out virtual files and devices early on

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=f2dc492df0f310aec97b5fc5847cca8d6cb70a33

commit f2dc492df0f310aec97b5fc5847cca8d6cb70a33
Author: Corinna Vinschen <corinna@vinschen.de>
Date:   Tue Feb 22 13:32:29 2022 +0100

    Cygwin: unlink: filter out virtual files and devices early on
    
    Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

Diff:
---
 winsup/cygwin/devices.h   | 1 +
 winsup/cygwin/syscalls.cc | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/winsup/cygwin/devices.h b/winsup/cygwin/devices.h
index fbbde6ab9..8f718dd17 100644
--- a/winsup/cygwin/devices.h
+++ b/winsup/cygwin/devices.h
@@ -433,6 +433,7 @@ extern const _device dev_fs_storage;
 #define iscygdrive_dev(devn) (devn == FH_CYGDRIVE)
 
 #define isdev_dev(devn) (devn == FH_DEV)
+#define isdevfd_dev(devn) (devn == FH_DEV_FD)
 
 #define isprocsys_dev(devn) (devn == FH_PROCSYS)
 
diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index 661c14347..24ec01da8 100644
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -1123,7 +1123,11 @@ unlink (const char *ourname)
       set_errno (EROFS);
       goto done;
     }
-
+  if (isdevfd_dev (devn) || (win32_name.isdevice () && !win32_name.issocket ()))
+    {
+      set_errno (EPERM);
+      goto done;
+    }
   if (!win32_name.exists ())
     {
       debug_printf ("unlinking a nonexistent file");