132 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			132 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
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| #ifndef _LINUX_RSEQ_H
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| #define _LINUX_RSEQ_H
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| 
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| #ifdef CONFIG_RSEQ
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| 
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| #include <linux/preempt.h>
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| #include <linux/sched.h>
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| 
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| /*
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|  * Map the event mask on the user-space ABI enum rseq_cs_flags
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|  * for direct mask checks.
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|  */
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| enum rseq_event_mask_bits {
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| 	RSEQ_EVENT_PREEMPT_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
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| 	RSEQ_EVENT_SIGNAL_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
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| 	RSEQ_EVENT_MIGRATE_BIT	= RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
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| };
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| 
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| enum rseq_event_mask {
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| 	RSEQ_EVENT_PREEMPT	= (1U << RSEQ_EVENT_PREEMPT_BIT),
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| 	RSEQ_EVENT_SIGNAL	= (1U << RSEQ_EVENT_SIGNAL_BIT),
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| 	RSEQ_EVENT_MIGRATE	= (1U << RSEQ_EVENT_MIGRATE_BIT),
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| };
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| 
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| static inline void rseq_set_notify_resume(struct task_struct *t)
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| {
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| 	if (t->rseq)
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| 		set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
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| }
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| 
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| void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
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| 
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| static inline void rseq_handle_notify_resume(struct ksignal *ksig,
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| 					     struct pt_regs *regs)
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| {
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| 	if (current->rseq)
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| 		__rseq_handle_notify_resume(ksig, regs);
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| }
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| 
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| static inline void rseq_signal_deliver(struct ksignal *ksig,
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| 				       struct pt_regs *regs)
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| {
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| 	preempt_disable();
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| 	__set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask);
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| 	preempt_enable();
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| 	rseq_handle_notify_resume(ksig, regs);
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| }
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| 
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| /* rseq_preempt() requires preemption to be disabled. */
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| static inline void rseq_preempt(struct task_struct *t)
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| {
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| 	__set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
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| 	rseq_set_notify_resume(t);
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| }
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| 
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| /* rseq_migrate() requires preemption to be disabled. */
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| static inline void rseq_migrate(struct task_struct *t)
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| {
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| 	__set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
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| 	rseq_set_notify_resume(t);
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| }
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| 
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| /*
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|  * If parent process has a registered restartable sequences area, the
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|  * child inherits. Unregister rseq for a clone with CLONE_VM set.
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|  */
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| static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
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| {
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| 	if (clone_flags & CLONE_VM) {
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| 		t->rseq = NULL;
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| 		t->rseq_len = 0;
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| 		t->rseq_sig = 0;
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| 		t->rseq_event_mask = 0;
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| 	} else {
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| 		t->rseq = current->rseq;
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| 		t->rseq_len = current->rseq_len;
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| 		t->rseq_sig = current->rseq_sig;
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| 		t->rseq_event_mask = current->rseq_event_mask;
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| 	}
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| }
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| 
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| static inline void rseq_execve(struct task_struct *t)
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| {
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| 	t->rseq = NULL;
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| 	t->rseq_len = 0;
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| 	t->rseq_sig = 0;
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| 	t->rseq_event_mask = 0;
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| }
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| 
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| #else
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| 
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| static inline void rseq_set_notify_resume(struct task_struct *t)
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| {
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| }
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| static inline void rseq_handle_notify_resume(struct ksignal *ksig,
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| 					     struct pt_regs *regs)
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| {
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| }
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| static inline void rseq_signal_deliver(struct ksignal *ksig,
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| 				       struct pt_regs *regs)
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| {
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| }
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| static inline void rseq_preempt(struct task_struct *t)
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| {
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| }
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| static inline void rseq_migrate(struct task_struct *t)
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| {
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| }
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| static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
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| {
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| }
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| static inline void rseq_execve(struct task_struct *t)
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| {
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| }
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| 
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| #endif
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| 
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| #ifdef CONFIG_DEBUG_RSEQ
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| 
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| void rseq_syscall(struct pt_regs *regs);
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| 
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| #else
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| 
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| static inline void rseq_syscall(struct pt_regs *regs)
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| {
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| }
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| 
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| #endif
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| 
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| #endif /* _LINUX_RSEQ_H */
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