1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _LINUX_UPROBES_H
3 #define _LINUX_UPROBES_H
4 /*
5  * User-space Probes (UProbes)
6  *
7  * Copyright (C) IBM Corporation, 2008-2012
8  * Authors:
9  *	Srikar Dronamraju
10  *	Jim Keniston
11  * Copyright (C) 2011-2012 Red Hat, Inc., Peter Zijlstra
12  */
13 
14 #include <linux/errno.h>
15 #include <linux/rbtree.h>
16 #include <linux/types.h>
17 #include <linux/wait.h>
18 
19 struct vm_area_struct;
20 struct mm_struct;
21 struct inode;
22 struct notifier_block;
23 struct page;
24 
25 #define UPROBE_HANDLER_REMOVE		1
26 #define UPROBE_HANDLER_MASK		1
27 
28 #define MAX_URETPROBE_DEPTH		64
29 
30 enum uprobe_filter_ctx {
31 	UPROBE_FILTER_REGISTER,
32 	UPROBE_FILTER_UNREGISTER,
33 	UPROBE_FILTER_MMAP,
34 };
35 
36 struct uprobe_consumer {
37 	int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs);
38 	int (*ret_handler)(struct uprobe_consumer *self,
39 				unsigned long func,
40 				struct pt_regs *regs);
41 	bool (*filter)(struct uprobe_consumer *self,
42 				enum uprobe_filter_ctx ctx,
43 				struct mm_struct *mm);
44 
45 	struct uprobe_consumer *next;
46 };
47 
48 #ifdef CONFIG_UPROBES
49 #include <asm/uprobes.h>
50 
51 enum uprobe_task_state {
52 	UTASK_RUNNING,
53 	UTASK_SSTEP,
54 	UTASK_SSTEP_ACK,
55 	UTASK_SSTEP_TRAPPED,
56 };
57 
58 /*
59  * uprobe_task: Metadata of a task while it singlesteps.
60  */
61 struct uprobe_task {
62 	enum uprobe_task_state		state;
63 
64 	union {
65 		struct {
66 			struct arch_uprobe_task	autask;
67 			unsigned long		vaddr;
68 		};
69 
70 		struct {
71 			struct callback_head	dup_xol_work;
72 			unsigned long		dup_xol_addr;
73 		};
74 	};
75 
76 	struct uprobe			*active_uprobe;
77 	unsigned long			xol_vaddr;
78 
79 	struct return_instance		*return_instances;
80 	unsigned int			depth;
81 };
82 
83 struct return_instance {
84 	struct uprobe		*uprobe;
85 	unsigned long		func;
86 	unsigned long		stack;		/* stack pointer */
87 	unsigned long		orig_ret_vaddr; /* original return address */
88 	bool			chained;	/* true, if instance is nested */
89 
90 	struct return_instance	*next;		/* keep as stack */
91 };
92 
93 enum rp_check {
94 	RP_CHECK_CALL,
95 	RP_CHECK_CHAIN_CALL,
96 	RP_CHECK_RET,
97 };
98 
99 struct xol_area;
100 
101 struct uprobes_state {
102 	struct xol_area		*xol_area;
103 };
104 
105 extern void __init uprobes_init(void);
106 extern int set_swbp(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
107 extern int set_orig_insn(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
108 extern bool is_swbp_insn(uprobe_opcode_t *insn);
109 extern bool is_trap_insn(uprobe_opcode_t *insn);
110 extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs);
111 extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
112 extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_t);
113 extern int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
114 extern int uprobe_register_refctr(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
115 extern int uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool);
116 extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
117 extern int uprobe_mmap(struct vm_area_struct *vma);
118 extern void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end);
119 extern void uprobe_start_dup_mmap(void);
120 extern void uprobe_end_dup_mmap(void);
121 extern void uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm);
122 extern void uprobe_free_utask(struct task_struct *t);
123 extern void uprobe_copy_process(struct task_struct *t, unsigned long flags);
124 extern int uprobe_post_sstep_notifier(struct pt_regs *regs);
125 extern int uprobe_pre_sstep_notifier(struct pt_regs *regs);
126 extern void uprobe_notify_resume(struct pt_regs *regs);
127 extern bool uprobe_deny_signal(void);
128 extern bool arch_uprobe_skip_sstep(struct arch_uprobe *aup, struct pt_regs *regs);
129 extern void uprobe_clear_state(struct mm_struct *mm);
130 extern int  arch_uprobe_analyze_insn(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long addr);
131 extern int  arch_uprobe_pre_xol(struct arch_uprobe *aup, struct pt_regs *regs);
132 extern int  arch_uprobe_post_xol(struct arch_uprobe *aup, struct pt_regs *regs);
133 extern bool arch_uprobe_xol_was_trapped(struct task_struct *tsk);
134 extern int  arch_uprobe_exception_notify(struct notifier_block *self, unsigned long val, void *data);
135 extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs);
136 extern unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs);
137 extern bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx, struct pt_regs *regs);
138 extern bool arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs);
139 extern void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,
140 					 void *src, unsigned long len);
141 #else /* !CONFIG_UPROBES */
142 struct uprobes_state {
143 };
144 
uprobes_init(void)145 static inline void uprobes_init(void)
146 {
147 }
148 
149 #define uprobe_get_trap_addr(regs)	instruction_pointer(regs)
150 
151 static inline int
uprobe_register(struct inode * inode,loff_t offset,struct uprobe_consumer * uc)152 uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
153 {
154 	return -ENOSYS;
155 }
uprobe_register_refctr(struct inode * inode,loff_t offset,loff_t ref_ctr_offset,struct uprobe_consumer * uc)156 static inline int uprobe_register_refctr(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc)
157 {
158 	return -ENOSYS;
159 }
160 static inline int
uprobe_apply(struct inode * inode,loff_t offset,struct uprobe_consumer * uc,bool add)161 uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool add)
162 {
163 	return -ENOSYS;
164 }
165 static inline void
uprobe_unregister(struct inode * inode,loff_t offset,struct uprobe_consumer * uc)166 uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
167 {
168 }
uprobe_mmap(struct vm_area_struct * vma)169 static inline int uprobe_mmap(struct vm_area_struct *vma)
170 {
171 	return 0;
172 }
173 static inline void
uprobe_munmap(struct vm_area_struct * vma,unsigned long start,unsigned long end)174 uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end)
175 {
176 }
uprobe_start_dup_mmap(void)177 static inline void uprobe_start_dup_mmap(void)
178 {
179 }
uprobe_end_dup_mmap(void)180 static inline void uprobe_end_dup_mmap(void)
181 {
182 }
183 static inline void
uprobe_dup_mmap(struct mm_struct * oldmm,struct mm_struct * newmm)184 uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm)
185 {
186 }
uprobe_notify_resume(struct pt_regs * regs)187 static inline void uprobe_notify_resume(struct pt_regs *regs)
188 {
189 }
uprobe_deny_signal(void)190 static inline bool uprobe_deny_signal(void)
191 {
192 	return false;
193 }
uprobe_free_utask(struct task_struct * t)194 static inline void uprobe_free_utask(struct task_struct *t)
195 {
196 }
uprobe_copy_process(struct task_struct * t,unsigned long flags)197 static inline void uprobe_copy_process(struct task_struct *t, unsigned long flags)
198 {
199 }
uprobe_clear_state(struct mm_struct * mm)200 static inline void uprobe_clear_state(struct mm_struct *mm)
201 {
202 }
203 #endif /* !CONFIG_UPROBES */
204 #endif	/* _LINUX_UPROBES_H */
205