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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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C
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#ifndef _LINUX_SCS_H#define _LINUX_SCS_H
#include <linux/gfp.h>#include <linux/poison.h>#include <linux/sched.h>#include <linux/sizes.h>
#ifdef CONFIG_SHADOW_CALL_STACK
#define SCS_ORDER 0#define SCS_SIZE (PAGE_SIZE << SCS_ORDER)#define GFP_SCS (GFP_KERNEL | __GFP_ZERO)
/* An illegal pointer value to mark the end of the shadow stack. */#define SCS_END_MAGIC (0x5f6UL + POISON_POINTER_DELTA)
#define task_scs(tsk) (task_thread_info(tsk)->scs_base)#define task_scs_sp(tsk) (task_thread_info(tsk)->scs_sp)
void *scs_alloc(int node);void scs_free(void *s);void scs_init(void);int scs_prepare(struct task_struct *tsk, int node);void scs_release(struct task_struct *tsk);
static inline void scs_task_reset(struct task_struct *tsk){ /* * Reset the shadow stack to the base address in case the task * is reused. */ task_scs_sp(tsk) = task_scs(tsk);}
static inline unsigned long *__scs_magic(void *s){ return (unsigned long *)(s + SCS_SIZE) - 1;}
static inline bool task_scs_end_corrupted(struct task_struct *tsk){ unsigned long *magic = __scs_magic(task_scs(tsk)); unsigned long sz = task_scs_sp(tsk) - task_scs(tsk);
return sz >= SCS_SIZE - 1 || READ_ONCE_NOCHECK(*magic) != SCS_END_MAGIC;}
DECLARE_STATIC_KEY_FALSE(dynamic_scs_enabled);
static inline bool scs_is_dynamic(void){ if (!IS_ENABLED(CONFIG_DYNAMIC_SCS)) return false; return static_branch_likely(&dynamic_scs_enabled);}
static inline bool scs_is_enabled(void){ if (!IS_ENABLED(CONFIG_DYNAMIC_SCS)) return true; return scs_is_dynamic();}
#else /* CONFIG_SHADOW_CALL_STACK */
static inline void *scs_alloc(int node) { return NULL; }static inline void scs_free(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 void scs_release(struct task_struct *tsk) {}static inline bool task_scs_end_corrupted(struct task_struct *tsk) { return false; }static inline bool scs_is_enabled(void) { return false; }static inline bool scs_is_dynamic(void) { return false; }
#endif /* CONFIG_SHADOW_CALL_STACK */
#endif /* _LINUX_SCS_H */