You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
57 lines
1.6 KiB
57 lines
1.6 KiB
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Shadow Call Stack support.
|
|
*
|
|
* Copyright (C) 2019 Google LLC
|
|
*/
|
|
|
|
#ifndef _LINUX_SCS_H
|
|
#define _LINUX_SCS_H
|
|
|
|
#include <linux/gfp.h>
|
|
#include <linux/sched.h>
|
|
#include <asm/page.h>
|
|
|
|
#ifdef CONFIG_SHADOW_CALL_STACK
|
|
|
|
/*
|
|
* In testing, 1 KiB shadow stack size (i.e. 128 stack frames on a 64-bit
|
|
* architecture) provided ~40% safety margin on stack usage while keeping
|
|
* memory allocation overhead reasonable.
|
|
*/
|
|
#define SCS_SIZE 1024UL
|
|
#define GFP_SCS (GFP_KERNEL | __GFP_ZERO)
|
|
|
|
/*
|
|
* A random number outside the kernel's virtual address space to mark the
|
|
* end of the shadow stack.
|
|
*/
|
|
#define SCS_END_MAGIC 0xaf0194819b1635f6UL
|
|
|
|
#define task_scs(tsk) (task_thread_info(tsk)->shadow_call_stack)
|
|
|
|
static inline void task_set_scs(struct task_struct *tsk, void *s)
|
|
{
|
|
task_scs(tsk) = s;
|
|
}
|
|
|
|
extern void scs_init(void);
|
|
extern void scs_task_reset(struct task_struct *tsk);
|
|
extern int scs_prepare(struct task_struct *tsk, int node);
|
|
extern bool scs_corrupted(struct task_struct *tsk);
|
|
extern void scs_release(struct task_struct *tsk);
|
|
|
|
#else /* CONFIG_SHADOW_CALL_STACK */
|
|
|
|
#define task_scs(tsk) NULL
|
|
|
|
static inline void task_set_scs(struct task_struct *tsk, void *s) {}
|
|
static inline void scs_init(void) {}
|
|
static inline void scs_task_reset(struct task_struct *tsk) {}
|
|
static inline int scs_prepare(struct task_struct *tsk, int node) { return 0; }
|
|
static inline bool scs_corrupted(struct task_struct *tsk) { return false; }
|
|
static inline void scs_release(struct task_struct *tsk) {}
|
|
|
|
#endif /* CONFIG_SHADOW_CALL_STACK */
|
|
|
|
#endif /* _LINUX_SCS_H */
|
|
|