glibc/sysdeps/unix/sysv/linux/x86/pkey_set.c

36 lines
1.2 KiB
C

/* Changing the per-thread memory protection key, x86_64 version.
Copyright (C) 2017-2020 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
<https://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;
}