// SPDX-License-Identifier: GPL-2.0
|
/*
|
* (C) Copyright 2002 Linus Torvalds
|
* Portions based on the vdso-randomization code from exec-shield:
|
* Copyright(C) 2005-2006, Red Hat, Inc., Ingo Molnar
|
*
|
* This file contains the needed initializations to support sysenter.
|
*/
|
|
#include <linux/init.h>
|
#include <linux/smp.h>
|
#include <linux/kernel.h>
|
#include <linux/mm_types.h>
|
#include <linux/elf.h>
|
|
#include <asm/processor.h>
|
#include <asm/vdso.h>
|
|
#ifdef CONFIG_COMPAT_VDSO
|
#define VDSO_DEFAULT 0
|
#else
|
#define VDSO_DEFAULT 1
|
#endif
|
|
/*
|
* Should the kernel map a VDSO page into processes and pass its
|
* address down to glibc upon exec()?
|
*/
|
unsigned int __read_mostly vdso32_enabled = VDSO_DEFAULT;
|
|
static int __init vdso32_setup(char *s)
|
{
|
vdso32_enabled = simple_strtoul(s, NULL, 0);
|
|
if (vdso32_enabled > 1) {
|
pr_warn("vdso32 values other than 0 and 1 are no longer allowed; vdso disabled\n");
|
vdso32_enabled = 0;
|
}
|
|
return 1;
|
}
|
|
/*
|
* For consistency, the argument vdso32=[012] affects the 32-bit vDSO
|
* behavior on both 64-bit and 32-bit kernels.
|
* On 32-bit kernels, vdso=[012] means the same thing.
|
*/
|
__setup("vdso32=", vdso32_setup);
|
|
#ifdef CONFIG_X86_32
|
__setup_param("vdso=", vdso_setup, vdso32_setup, 0);
|
#endif
|
|
int __init sysenter_setup(void)
|
{
|
init_vdso_image(&vdso_image_32);
|
|
return 0;
|
}
|
|
#ifdef CONFIG_X86_64
|
|
subsys_initcall(sysenter_setup);
|
|
#ifdef CONFIG_SYSCTL
|
/* Register vsyscall32 into the ABI table */
|
#include <linux/sysctl.h>
|
|
static const int zero;
|
static const int one = 1;
|
|
static struct ctl_table abi_table2[] = {
|
{
|
.procname = "vsyscall32",
|
.data = &vdso32_enabled,
|
.maxlen = sizeof(int),
|
.mode = 0644,
|
.proc_handler = proc_dointvec_minmax,
|
.extra1 = (int *)&zero,
|
.extra2 = (int *)&one,
|
},
|
{}
|
};
|
|
static struct ctl_table abi_root_table2[] = {
|
{
|
.procname = "abi",
|
.mode = 0555,
|
.child = abi_table2
|
},
|
{}
|
};
|
|
static __init int ia32_binfmt_init(void)
|
{
|
register_sysctl_table(abi_root_table2);
|
return 0;
|
}
|
__initcall(ia32_binfmt_init);
|
#endif /* CONFIG_SYSCTL */
|
|
#endif /* CONFIG_X86_64 */
|
