mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-08-05 16:54:27 +00:00
a33e288147
When CONFIG_X86_32 is defined and CONFIG_UML is not defined, vdso_enabled belongs to arch/x86/entry/vdso/vdso32-setup.c. So, move it into its own file. Before this patch, vdso_enabled was allowed to be set to a value exceeding 1 on x86_32 architecture. After this patch is applied, vdso_enabled is not permitted to set the value more than 1. It does not matter, because according to the function load_vdso32(), only vdso_enabled is set to 1, VDSO would be enabled. Other values all mean "disabled". The same limitation could be seen in the function vdso32_setup(). Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com> Reviewed-by: Kees Cook <kees@kernel.org> Signed-off-by: Joel Granados <joel.granados@kernel.org>
86 lines
1.8 KiB
C
86 lines
1.8 KiB
C
// 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
|
|
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
#include <linux/sysctl.h>
|
|
|
|
static const struct ctl_table vdso_table[] = {
|
|
{
|
|
#ifdef CONFIG_X86_64
|
|
.procname = "vsyscall32",
|
|
#else
|
|
.procname = "vdso_enabled",
|
|
#endif
|
|
.data = &vdso32_enabled,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = SYSCTL_ZERO,
|
|
.extra2 = SYSCTL_ONE,
|
|
},
|
|
};
|
|
|
|
static __init int ia32_binfmt_init(void)
|
|
{
|
|
#ifdef CONFIG_X86_64
|
|
/* Register vsyscall32 into the ABI table */
|
|
register_sysctl("abi", vdso_table);
|
|
#else
|
|
register_sysctl_init("vm", vdso_table);
|
|
#endif
|
|
return 0;
|
|
}
|
|
__initcall(ia32_binfmt_init);
|
|
#endif /* CONFIG_SYSCTL */
|
|
|