1
2#ifndef _LINUX_KPROBES_H
3#define _LINUX_KPROBES_H
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19#include <linux/compiler.h>
20#include <linux/linkage.h>
21#include <linux/list.h>
22#include <linux/notifier.h>
23#include <linux/smp.h>
24#include <linux/bug.h>
25#include <linux/percpu.h>
26#include <linux/spinlock.h>
27#include <linux/rcupdate.h>
28#include <linux/mutex.h>
29#include <linux/ftrace.h>
30#include <linux/refcount.h>
31#include <linux/freelist.h>
32#include <asm/kprobes.h>
33
34#ifdef CONFIG_KPROBES
35
36
37#define KPROBE_HIT_ACTIVE 0x00000001
38#define KPROBE_HIT_SS 0x00000002
39#define KPROBE_REENTER 0x00000004
40#define KPROBE_HIT_SSDONE 0x00000008
41
42#else
43#include <asm-generic/kprobes.h>
44typedef int kprobe_opcode_t;
45struct arch_specific_insn {
46 int dummy;
47};
48#endif
49
50struct kprobe;
51struct pt_regs;
52struct kretprobe;
53struct kretprobe_instance;
54typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *);
55typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *,
56 unsigned long flags);
57typedef int (*kretprobe_handler_t) (struct kretprobe_instance *,
58 struct pt_regs *);
59
60struct kprobe {
61 struct hlist_node hlist;
62
63
64 struct list_head list;
65
66
67 unsigned long nmissed;
68
69
70 kprobe_opcode_t *addr;
71
72
73 const char *symbol_name;
74
75
76 unsigned int offset;
77
78
79 kprobe_pre_handler_t pre_handler;
80
81
82 kprobe_post_handler_t post_handler;
83
84
85 kprobe_opcode_t opcode;
86
87
88 struct arch_specific_insn ainsn;
89
90
91
92
93
94 u32 flags;
95};
96
97
98#define KPROBE_FLAG_GONE 1
99#define KPROBE_FLAG_DISABLED 2
100#define KPROBE_FLAG_OPTIMIZED 4
101
102
103
104
105#define KPROBE_FLAG_FTRACE 8
106
107
108static inline int kprobe_gone(struct kprobe *p)
109{
110 return p->flags & KPROBE_FLAG_GONE;
111}
112
113
114static inline int kprobe_disabled(struct kprobe *p)
115{
116 return p->flags & (KPROBE_FLAG_DISABLED | KPROBE_FLAG_GONE);
117}
118
119
120static inline int kprobe_optimized(struct kprobe *p)
121{
122 return p->flags & KPROBE_FLAG_OPTIMIZED;
123}
124
125
126static inline int kprobe_ftrace(struct kprobe *p)
127{
128 return p->flags & KPROBE_FLAG_FTRACE;
129}
130
131
132
133
134
135
136
137
138
139
140
141struct kretprobe_holder {
142 struct kretprobe *rp;
143 refcount_t ref;
144};
145
146struct kretprobe {
147 struct kprobe kp;
148 kretprobe_handler_t handler;
149 kretprobe_handler_t entry_handler;
150 int maxactive;
151 int nmissed;
152 size_t data_size;
153 struct freelist_head freelist;
154 struct kretprobe_holder *rph;
155};
156
157struct kretprobe_instance {
158 union {
159 struct freelist_node freelist;
160 struct rcu_head rcu;
161 };
162 struct llist_node llist;
163 struct kretprobe_holder *rph;
164 kprobe_opcode_t *ret_addr;
165 void *fp;
166 char data[];
167};
168
169struct kretprobe_blackpoint {
170 const char *name;
171 void *addr;
172};
173
174struct kprobe_blacklist_entry {
175 struct list_head list;
176 unsigned long start_addr;
177 unsigned long end_addr;
178};
179
180#ifdef CONFIG_KPROBES
181DECLARE_PER_CPU(struct kprobe *, current_kprobe);
182DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
183
184
185
186
187static inline int kprobes_built_in(void)
188{
189 return 1;
190}
191
192extern void kprobe_busy_begin(void);
193extern void kprobe_busy_end(void);
194
195#ifdef CONFIG_KRETPROBES
196extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
197 struct pt_regs *regs);
198extern int arch_trampoline_kprobe(struct kprobe *p);
199
200
201unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs,
202 void *trampoline_address,
203 void *frame_pointer);
204
205static nokprobe_inline
206unsigned long kretprobe_trampoline_handler(struct pt_regs *regs,
207 void *trampoline_address,
208 void *frame_pointer)
209{
210 unsigned long ret;
211
212
213
214
215
216 kprobe_busy_begin();
217 ret = __kretprobe_trampoline_handler(regs, trampoline_address, frame_pointer);
218 kprobe_busy_end();
219
220 return ret;
221}
222
223static nokprobe_inline struct kretprobe *get_kretprobe(struct kretprobe_instance *ri)
224{
225 RCU_LOCKDEP_WARN(!rcu_read_lock_any_held(),
226 "Kretprobe is accessed from instance under preemptive context");
227
228 return READ_ONCE(ri->rph->rp);
229}
230
231#else
232static inline void arch_prepare_kretprobe(struct kretprobe *rp,
233 struct pt_regs *regs)
234{
235}
236static inline int arch_trampoline_kprobe(struct kprobe *p)
237{
238 return 0;
239}
240#endif
241
242extern struct kretprobe_blackpoint kretprobe_blacklist[];
243
244#ifdef CONFIG_KPROBES_SANITY_TEST
245extern int init_test_probes(void);
246#else
247static inline int init_test_probes(void)
248{
249 return 0;
250}
251#endif
252
253extern int arch_prepare_kprobe(struct kprobe *p);
254extern void arch_arm_kprobe(struct kprobe *p);
255extern void arch_disarm_kprobe(struct kprobe *p);
256extern int arch_init_kprobes(void);
257extern void kprobes_inc_nmissed_count(struct kprobe *p);
258extern bool arch_within_kprobe_blacklist(unsigned long addr);
259extern int arch_populate_kprobe_blacklist(void);
260extern bool arch_kprobe_on_func_entry(unsigned long offset);
261extern int kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset);
262
263extern bool within_kprobe_blacklist(unsigned long addr);
264extern int kprobe_add_ksym_blacklist(unsigned long entry);
265extern int kprobe_add_area_blacklist(unsigned long start, unsigned long end);
266
267struct kprobe_insn_cache {
268 struct mutex mutex;
269 void *(*alloc)(void);
270 void (*free)(void *);
271 const char *sym;
272 struct list_head pages;
273 size_t insn_size;
274 int nr_garbage;
275};
276
277#ifdef __ARCH_WANT_KPROBES_INSN_SLOT
278extern kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c);
279extern void __free_insn_slot(struct kprobe_insn_cache *c,
280 kprobe_opcode_t *slot, int dirty);
281
282extern bool __is_insn_slot_addr(struct kprobe_insn_cache *c,
283 unsigned long addr);
284
285#define DEFINE_INSN_CACHE_OPS(__name) \
286extern struct kprobe_insn_cache kprobe_##__name##_slots; \
287 \
288static inline kprobe_opcode_t *get_##__name##_slot(void) \
289{ \
290 return __get_insn_slot(&kprobe_##__name##_slots); \
291} \
292 \
293static inline void free_##__name##_slot(kprobe_opcode_t *slot, int dirty)\
294{ \
295 __free_insn_slot(&kprobe_##__name##_slots, slot, dirty); \
296} \
297 \
298static inline bool is_kprobe_##__name##_slot(unsigned long addr) \
299{ \
300 return __is_insn_slot_addr(&kprobe_##__name##_slots, addr); \
301}
302#define KPROBE_INSN_PAGE_SYM "kprobe_insn_page"
303#define KPROBE_OPTINSN_PAGE_SYM "kprobe_optinsn_page"
304int kprobe_cache_get_kallsym(struct kprobe_insn_cache *c, unsigned int *symnum,
305 unsigned long *value, char *type, char *sym);
306#else
307#define DEFINE_INSN_CACHE_OPS(__name) \
308static inline bool is_kprobe_##__name##_slot(unsigned long addr) \
309{ \
310 return 0; \
311}
312#endif
313
314DEFINE_INSN_CACHE_OPS(insn);
315
316#ifdef CONFIG_OPTPROBES
317
318
319
320struct optimized_kprobe {
321 struct kprobe kp;
322 struct list_head list;
323 struct arch_optimized_insn optinsn;
324};
325
326
327extern int arch_prepared_optinsn(struct arch_optimized_insn *optinsn);
328extern int arch_check_optimized_kprobe(struct optimized_kprobe *op);
329extern int arch_prepare_optimized_kprobe(struct optimized_kprobe *op,
330 struct kprobe *orig);
331extern void arch_remove_optimized_kprobe(struct optimized_kprobe *op);
332extern void arch_optimize_kprobes(struct list_head *oplist);
333extern void arch_unoptimize_kprobes(struct list_head *oplist,
334 struct list_head *done_list);
335extern void arch_unoptimize_kprobe(struct optimized_kprobe *op);
336extern int arch_within_optimized_kprobe(struct optimized_kprobe *op,
337 unsigned long addr);
338
339extern void opt_pre_handler(struct kprobe *p, struct pt_regs *regs);
340
341DEFINE_INSN_CACHE_OPS(optinsn);
342
343#ifdef CONFIG_SYSCTL
344extern int sysctl_kprobes_optimization;
345extern int proc_kprobes_optimization_handler(struct ctl_table *table,
346 int write, void *buffer,
347 size_t *length, loff_t *ppos);
348#endif
349extern void wait_for_kprobe_optimizer(void);
350#else
351static inline void wait_for_kprobe_optimizer(void) { }
352#endif
353#ifdef CONFIG_KPROBES_ON_FTRACE
354extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
355 struct ftrace_ops *ops, struct ftrace_regs *fregs);
356extern int arch_prepare_kprobe_ftrace(struct kprobe *p);
357#endif
358
359int arch_check_ftrace_location(struct kprobe *p);
360
361
362struct kprobe *get_kprobe(void *addr);
363
364
365static inline struct kprobe *kprobe_running(void)
366{
367 return (__this_cpu_read(current_kprobe));
368}
369
370static inline void reset_current_kprobe(void)
371{
372 __this_cpu_write(current_kprobe, NULL);
373}
374
375static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void)
376{
377 return this_cpu_ptr(&kprobe_ctlblk);
378}
379
380kprobe_opcode_t *kprobe_lookup_name(const char *name, unsigned int offset);
381int register_kprobe(struct kprobe *p);
382void unregister_kprobe(struct kprobe *p);
383int register_kprobes(struct kprobe **kps, int num);
384void unregister_kprobes(struct kprobe **kps, int num);
385unsigned long arch_deref_entry_point(void *);
386
387int register_kretprobe(struct kretprobe *rp);
388void unregister_kretprobe(struct kretprobe *rp);
389int register_kretprobes(struct kretprobe **rps, int num);
390void unregister_kretprobes(struct kretprobe **rps, int num);
391
392void kprobe_flush_task(struct task_struct *tk);
393
394void kprobe_free_init_mem(void);
395
396int disable_kprobe(struct kprobe *kp);
397int enable_kprobe(struct kprobe *kp);
398
399void dump_kprobe(struct kprobe *kp);
400
401void *alloc_insn_page(void);
402
403void *alloc_optinsn_page(void);
404void free_optinsn_page(void *page);
405
406int kprobe_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
407 char *sym);
408
409int arch_kprobe_get_kallsym(unsigned int *symnum, unsigned long *value,
410 char *type, char *sym);
411#else
412
413static inline int kprobes_built_in(void)
414{
415 return 0;
416}
417static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
418{
419 return 0;
420}
421static inline struct kprobe *get_kprobe(void *addr)
422{
423 return NULL;
424}
425static inline struct kprobe *kprobe_running(void)
426{
427 return NULL;
428}
429static inline int register_kprobe(struct kprobe *p)
430{
431 return -ENOSYS;
432}
433static inline int register_kprobes(struct kprobe **kps, int num)
434{
435 return -ENOSYS;
436}
437static inline void unregister_kprobe(struct kprobe *p)
438{
439}
440static inline void unregister_kprobes(struct kprobe **kps, int num)
441{
442}
443static inline int register_kretprobe(struct kretprobe *rp)
444{
445 return -ENOSYS;
446}
447static inline int register_kretprobes(struct kretprobe **rps, int num)
448{
449 return -ENOSYS;
450}
451static inline void unregister_kretprobe(struct kretprobe *rp)
452{
453}
454static inline void unregister_kretprobes(struct kretprobe **rps, int num)
455{
456}
457static inline void kprobe_flush_task(struct task_struct *tk)
458{
459}
460static inline void kprobe_free_init_mem(void)
461{
462}
463static inline int disable_kprobe(struct kprobe *kp)
464{
465 return -ENOSYS;
466}
467static inline int enable_kprobe(struct kprobe *kp)
468{
469 return -ENOSYS;
470}
471
472static inline bool within_kprobe_blacklist(unsigned long addr)
473{
474 return true;
475}
476static inline int kprobe_get_kallsym(unsigned int symnum, unsigned long *value,
477 char *type, char *sym)
478{
479 return -ERANGE;
480}
481#endif
482static inline int disable_kretprobe(struct kretprobe *rp)
483{
484 return disable_kprobe(&rp->kp);
485}
486static inline int enable_kretprobe(struct kretprobe *rp)
487{
488 return enable_kprobe(&rp->kp);
489}
490
491#ifndef CONFIG_KPROBES
492static inline bool is_kprobe_insn_slot(unsigned long addr)
493{
494 return false;
495}
496#endif
497#ifndef CONFIG_OPTPROBES
498static inline bool is_kprobe_optinsn_slot(unsigned long addr)
499{
500 return false;
501}
502#endif
503
504
505static nokprobe_inline bool kprobe_page_fault(struct pt_regs *regs,
506 unsigned int trap)
507{
508 if (!kprobes_built_in())
509 return false;
510 if (user_mode(regs))
511 return false;
512
513
514
515
516 if (preemptible())
517 return false;
518 if (!kprobe_running())
519 return false;
520 return kprobe_fault_handler(regs, trap);
521}
522
523#endif
524