1 files changed, 35 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/x86/pkey_set.c b/sysdeps/unix/sysv/linux/x86/pkey_set.c
new file mode 100644
index 0000000000..ea061d6dd7
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/pkey_set.c
@@ -0,0 +1,35 @@
+/* Changing the per-thread memory protection key, x86_64 version.
+   Copyright (C) 2017-2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <arch-pkey.h>
+#include <errno.h>
+
+int
+pkey_set (int key, unsigned int rights)
+{
+  if (key < 0 || key > 15 || rights > 3)
+    {
+      __set_errno (EINVAL);
+      return -1;
+    }
+  unsigned int mask = 3 << (2 * key);
+  unsigned int pkru = pkey_read ();
+  pkru = (pkru & ~mask) | (rights << (2 * key));
+  pkey_write (pkru);
+  return 0;
+}