]> git.ipfire.org Git - thirdparty/kernel/stable.git/blame - include/linux/kprobes.h
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 503
[thirdparty/kernel/stable.git] / include / linux / kprobes.h
CommitLineData
1a59d1b8 1/* SPDX-License-Identifier: GPL-2.0-or-later */
1da177e4
LT
2#ifndef _LINUX_KPROBES_H
3#define _LINUX_KPROBES_H
4/*
5 * Kernel Probes (KProbes)
6 * include/linux/kprobes.h
7 *
1da177e4
LT
8 * Copyright (C) IBM Corporation, 2002, 2004
9 *
10 * 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
11 * Probes initial implementation ( includes suggestions from
12 * Rusty Russell).
13 * 2004-July Suparna Bhattacharya <suparna@in.ibm.com> added jumper probes
14 * interface to access function arguments.
b94cce92
HN
15 * 2005-May Hien Nguyen <hien@us.ibm.com> and Jim Keniston
16 * <jkenisto@us.ibm.com> and Prasanna S Panchamukhi
17 * <prasanna@in.ibm.com> added function-return probes.
1da177e4 18 */
7d134b2c 19#include <linux/compiler.h>
36dcd67a 20#include <linux/linkage.h>
1da177e4
LT
21#include <linux/list.h>
22#include <linux/notifier.h>
23#include <linux/smp.h>
187f1882 24#include <linux/bug.h>
e6584523 25#include <linux/percpu.h>
3516a460
AM
26#include <linux/spinlock.h>
27#include <linux/rcupdate.h>
7a7d1cf9 28#include <linux/mutex.h>
ae6aa16f 29#include <linux/ftrace.h>
7d134b2c 30#include <asm/kprobes.h>
b94cce92 31
00d7c05a 32#ifdef CONFIG_KPROBES
1da177e4 33
ea32c65c
PP
34/* kprobe_status settings */
35#define KPROBE_HIT_ACTIVE 0x00000001
36#define KPROBE_HIT_SS 0x00000002
37#define KPROBE_REENTER 0x00000004
38#define KPROBE_HIT_SSDONE 0x00000008
39
dc19835d 40#else /* CONFIG_KPROBES */
7d134b2c 41#include <asm-generic/kprobes.h>
dc19835d
MH
42typedef int kprobe_opcode_t;
43struct arch_specific_insn {
44 int dummy;
45};
dc19835d 46#endif /* CONFIG_KPROBES */
d0aaff97 47
1da177e4
LT
48struct kprobe;
49struct pt_regs;
b94cce92
HN
50struct kretprobe;
51struct kretprobe_instance;
1da177e4 52typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *);
1da177e4
LT
53typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *,
54 unsigned long flags);
55typedef int (*kprobe_fault_handler_t) (struct kprobe *, struct pt_regs *,
56 int trapnr);
b94cce92
HN
57typedef int (*kretprobe_handler_t) (struct kretprobe_instance *,
58 struct pt_regs *);
59
1da177e4
LT
60struct kprobe {
61 struct hlist_node hlist;
62
64f562c6
AM
63 /* list of kprobes for multi-handler support */
64 struct list_head list;
65
ea32c65c
PP
66 /*count the number of times this probe was temporarily disarmed */
67 unsigned long nmissed;
68
1da177e4
LT
69 /* location of the probe point */
70 kprobe_opcode_t *addr;
71
3a872d89 72 /* Allow user to indicate symbol name of the probe point */
9b3af29b 73 const char *symbol_name;
3a872d89
AM
74
75 /* Offset into the symbol */
76 unsigned int offset;
77
1da177e4
LT
78 /* Called before addr is executed. */
79 kprobe_pre_handler_t pre_handler;
80
81 /* Called after addr is executed, unless... */
82 kprobe_post_handler_t post_handler;
83
cc00e9cf
MH
84 /*
85 * ... called if executing addr causes a fault (eg. page fault).
86 * Return 1 if it handled fault, otherwise kernel will see it.
87 */
1da177e4
LT
88 kprobe_fault_handler_t fault_handler;
89
1da177e4
LT
90 /* Saved opcode (which has been replaced with breakpoint) */
91 kprobe_opcode_t opcode;
92
93 /* copy of the original instruction */
94 struct arch_specific_insn ainsn;
e8386a0c 95
de5bd88d
MH
96 /*
97 * Indicates various status flags.
98 * Protected by kprobe_mutex after this kprobe is registered.
99 */
e8386a0c 100 u32 flags;
1da177e4
LT
101};
102
e8386a0c
MH
103/* Kprobe status flags */
104#define KPROBE_FLAG_GONE 1 /* breakpoint has already gone */
de5bd88d 105#define KPROBE_FLAG_DISABLED 2 /* probe is temporarily disabled */
afd66255
MH
106#define KPROBE_FLAG_OPTIMIZED 4 /*
107 * probe is really optimized.
108 * NOTE:
109 * this flag is only for optimized_kprobe.
110 */
ae6aa16f 111#define KPROBE_FLAG_FTRACE 8 /* probe is using ftrace */
e8386a0c 112
de5bd88d 113/* Has this kprobe gone ? */
e8386a0c
MH
114static inline int kprobe_gone(struct kprobe *p)
115{
116 return p->flags & KPROBE_FLAG_GONE;
117}
118
de5bd88d
MH
119/* Is this kprobe disabled ? */
120static inline int kprobe_disabled(struct kprobe *p)
121{
122 return p->flags & (KPROBE_FLAG_DISABLED | KPROBE_FLAG_GONE);
123}
afd66255
MH
124
125/* Is this kprobe really running optimized path ? */
126static inline int kprobe_optimized(struct kprobe *p)
127{
128 return p->flags & KPROBE_FLAG_OPTIMIZED;
129}
ae6aa16f
MH
130
131/* Is this kprobe uses ftrace ? */
132static inline int kprobe_ftrace(struct kprobe *p)
133{
134 return p->flags & KPROBE_FLAG_FTRACE;
135}
136
b94cce92
HN
137/*
138 * Function-return probe -
139 * Note:
140 * User needs to provide a handler function, and initialize maxactive.
141 * maxactive - The maximum number of instances of the probed function that
142 * can be active concurrently.
143 * nmissed - tracks the number of times the probed function's return was
144 * ignored, due to maxactive being too low.
145 *
146 */
147struct kretprobe {
148 struct kprobe kp;
149 kretprobe_handler_t handler;
f47cd9b5 150 kretprobe_handler_t entry_handler;
b94cce92
HN
151 int maxactive;
152 int nmissed;
f47cd9b5 153 size_t data_size;
b94cce92 154 struct hlist_head free_instances;
ec484608 155 raw_spinlock_t lock;
b94cce92
HN
156};
157
158struct kretprobe_instance {
b94cce92
HN
159 struct hlist_node hlist;
160 struct kretprobe *rp;
802eae7c
RL
161 kprobe_opcode_t *ret_addr;
162 struct task_struct *task;
3ff9c075 163 void *fp;
f47cd9b5 164 char data[0];
b94cce92
HN
165};
166
f438d914
MH
167struct kretprobe_blackpoint {
168 const char *name;
169 void *addr;
170};
3d8d996e 171
376e2424
MH
172struct kprobe_blacklist_entry {
173 struct list_head list;
3d8d996e 174 unsigned long start_addr;
376e2424 175 unsigned long end_addr;
3d8d996e
SD
176};
177
dc19835d
MH
178#ifdef CONFIG_KPROBES
179DECLARE_PER_CPU(struct kprobe *, current_kprobe);
180DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
181
b1801812
IM
182/*
183 * For #ifdef avoidance:
184 */
185static inline int kprobes_built_in(void)
186{
187 return 1;
188}
189
dc19835d
MH
190#ifdef CONFIG_KRETPROBES
191extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
192 struct pt_regs *regs);
193extern int arch_trampoline_kprobe(struct kprobe *p);
194#else /* CONFIG_KRETPROBES */
195static inline void arch_prepare_kretprobe(struct kretprobe *rp,
196 struct pt_regs *regs)
197{
198}
199static inline int arch_trampoline_kprobe(struct kprobe *p)
200{
201 return 0;
202}
203#endif /* CONFIG_KRETPROBES */
204
f438d914
MH
205extern struct kretprobe_blackpoint kretprobe_blacklist[];
206
0f95b7fc
AM
207static inline void kretprobe_assert(struct kretprobe_instance *ri,
208 unsigned long orig_ret_address, unsigned long trampoline_address)
209{
210 if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
211 printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
212 ri->rp, ri->rp->kp.addr);
213 BUG();
214 }
215}
216
8c1c9356
AM
217#ifdef CONFIG_KPROBES_SANITY_TEST
218extern int init_test_probes(void);
219#else
220static inline int init_test_probes(void)
221{
222 return 0;
223}
224#endif /* CONFIG_KPROBES_SANITY_TEST */
225
1da177e4 226extern int arch_prepare_kprobe(struct kprobe *p);
7e1048b1
RL
227extern void arch_arm_kprobe(struct kprobe *p);
228extern void arch_disarm_kprobe(struct kprobe *p);
6772926b 229extern int arch_init_kprobes(void);
1da177e4 230extern void show_registers(struct pt_regs *regs);
bf8d5c52 231extern void kprobes_inc_nmissed_count(struct kprobe *p);
be8f2743 232extern bool arch_within_kprobe_blacklist(unsigned long addr);
fb1a59fa 233extern int arch_populate_kprobe_blacklist(void);
659b957f
NR
234extern bool arch_kprobe_on_func_entry(unsigned long offset);
235extern bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset);
1da177e4 236
e5779e8e 237extern bool within_kprobe_blacklist(unsigned long addr);
fb1a59fa
MH
238extern int kprobe_add_ksym_blacklist(unsigned long entry);
239extern int kprobe_add_area_blacklist(unsigned long start, unsigned long end);
e5779e8e 240
c802d64a
HC
241struct kprobe_insn_cache {
242 struct mutex mutex;
af96397d
HC
243 void *(*alloc)(void); /* allocate insn page */
244 void (*free)(void *); /* free insn page */
c802d64a
HC
245 struct list_head pages; /* list of kprobe_insn_page */
246 size_t insn_size; /* size of instruction slot */
247 int nr_garbage;
248};
249
5b485629 250#ifdef __ARCH_WANT_KPROBES_INSN_SLOT
c802d64a
HC
251extern kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c);
252extern void __free_insn_slot(struct kprobe_insn_cache *c,
253 kprobe_opcode_t *slot, int dirty);
5b485629
MH
254/* sleep-less address checking routine */
255extern bool __is_insn_slot_addr(struct kprobe_insn_cache *c,
256 unsigned long addr);
c802d64a
HC
257
258#define DEFINE_INSN_CACHE_OPS(__name) \
259extern struct kprobe_insn_cache kprobe_##__name##_slots; \
260 \
261static inline kprobe_opcode_t *get_##__name##_slot(void) \
262{ \
263 return __get_insn_slot(&kprobe_##__name##_slots); \
264} \
265 \
266static inline void free_##__name##_slot(kprobe_opcode_t *slot, int dirty)\
267{ \
268 __free_insn_slot(&kprobe_##__name##_slots, slot, dirty); \
269} \
5b485629
MH
270 \
271static inline bool is_kprobe_##__name##_slot(unsigned long addr) \
272{ \
273 return __is_insn_slot_addr(&kprobe_##__name##_slots, addr); \
274}
275#else /* __ARCH_WANT_KPROBES_INSN_SLOT */
276#define DEFINE_INSN_CACHE_OPS(__name) \
277static inline bool is_kprobe_##__name##_slot(unsigned long addr) \
278{ \
279 return 0; \
280}
281#endif
c802d64a
HC
282
283DEFINE_INSN_CACHE_OPS(insn);
284
afd66255
MH
285#ifdef CONFIG_OPTPROBES
286/*
287 * Internal structure for direct jump optimized probe
288 */
289struct optimized_kprobe {
290 struct kprobe kp;
291 struct list_head list; /* list for optimizing queue */
292 struct arch_optimized_insn optinsn;
293};
294
295/* Architecture dependent functions for direct jump optimization */
296extern int arch_prepared_optinsn(struct arch_optimized_insn *optinsn);
297extern int arch_check_optimized_kprobe(struct optimized_kprobe *op);
cbf6ab52
MH
298extern int arch_prepare_optimized_kprobe(struct optimized_kprobe *op,
299 struct kprobe *orig);
afd66255 300extern void arch_remove_optimized_kprobe(struct optimized_kprobe *op);
cd7ebe22 301extern void arch_optimize_kprobes(struct list_head *oplist);
f984ba4e
MH
302extern void arch_unoptimize_kprobes(struct list_head *oplist,
303 struct list_head *done_list);
afd66255 304extern void arch_unoptimize_kprobe(struct optimized_kprobe *op);
afd66255
MH
305extern int arch_within_optimized_kprobe(struct optimized_kprobe *op,
306 unsigned long addr);
307
308extern void opt_pre_handler(struct kprobe *p, struct pt_regs *regs);
b2be84df 309
c802d64a
HC
310DEFINE_INSN_CACHE_OPS(optinsn);
311
b2be84df
MH
312#ifdef CONFIG_SYSCTL
313extern int sysctl_kprobes_optimization;
314extern int proc_kprobes_optimization_handler(struct ctl_table *table,
315 int write, void __user *buffer,
316 size_t *length, loff_t *ppos);
317#endif
30e7d894
TG
318extern void wait_for_kprobe_optimizer(void);
319#else
320static inline void wait_for_kprobe_optimizer(void) { }
afd66255 321#endif /* CONFIG_OPTPROBES */
e7dbfe34 322#ifdef CONFIG_KPROBES_ON_FTRACE
ae6aa16f 323extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
e5253896 324 struct ftrace_ops *ops, struct pt_regs *regs);
ae6aa16f
MH
325extern int arch_prepare_kprobe_ftrace(struct kprobe *p);
326#endif
327
f7f242ff 328int arch_check_ftrace_location(struct kprobe *p);
afd66255 329
d217d545 330/* Get the kprobe at this addr (if any) - called with preemption disabled */
1da177e4 331struct kprobe *get_kprobe(void *addr);
ef53d9c5
S
332void kretprobe_hash_lock(struct task_struct *tsk,
333 struct hlist_head **head, unsigned long *flags);
334void kretprobe_hash_unlock(struct task_struct *tsk, unsigned long *flags);
b94cce92 335struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk);
1da177e4 336
e6584523
AM
337/* kprobe_running() will just return the current_kprobe on this CPU */
338static inline struct kprobe *kprobe_running(void)
339{
b76834bc 340 return (__this_cpu_read(current_kprobe));
e6584523
AM
341}
342
343static inline void reset_current_kprobe(void)
344{
b76834bc 345 __this_cpu_write(current_kprobe, NULL);
e6584523
AM
346}
347
348static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void)
349{
bdffd893 350 return this_cpu_ptr(&kprobe_ctlblk);
e6584523
AM
351}
352
290e3070 353kprobe_opcode_t *kprobe_lookup_name(const char *name, unsigned int offset);
1da177e4
LT
354int register_kprobe(struct kprobe *p);
355void unregister_kprobe(struct kprobe *p);
9861668f
MH
356int register_kprobes(struct kprobe **kps, int num);
357void unregister_kprobes(struct kprobe **kps, int num);
3d7e3382 358unsigned long arch_deref_entry_point(void *);
1da177e4 359
b94cce92
HN
360int register_kretprobe(struct kretprobe *rp);
361void unregister_kretprobe(struct kretprobe *rp);
4a296e07
MH
362int register_kretprobes(struct kretprobe **rps, int num);
363void unregister_kretprobes(struct kretprobe **rps, int num);
b94cce92 364
b94cce92 365void kprobe_flush_task(struct task_struct *tk);
99219a3f 366void recycle_rp_inst(struct kretprobe_instance *ri, struct hlist_head *head);
8c1c9356 367
de5bd88d
MH
368int disable_kprobe(struct kprobe *kp);
369int enable_kprobe(struct kprobe *kp);
370
24851d24
FW
371void dump_kprobe(struct kprobe *kp);
372
ad3bc25a
BP
373void *alloc_insn_page(void);
374void free_insn_page(void *page);
375
b1801812 376#else /* !CONFIG_KPROBES: */
00d7c05a 377
b1801812
IM
378static inline int kprobes_built_in(void)
379{
380 return 0;
381}
382static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
383{
384 return 0;
385}
785656a4
AS
386static inline struct kprobe *get_kprobe(void *addr)
387{
388 return NULL;
389}
e6584523 390static inline struct kprobe *kprobe_running(void)
1da177e4 391{
e6584523 392 return NULL;
1da177e4
LT
393}
394static inline int register_kprobe(struct kprobe *p)
395{
396 return -ENOSYS;
397}
9861668f
MH
398static inline int register_kprobes(struct kprobe **kps, int num)
399{
400 return -ENOSYS;
401}
1da177e4
LT
402static inline void unregister_kprobe(struct kprobe *p)
403{
404}
9861668f
MH
405static inline void unregister_kprobes(struct kprobe **kps, int num)
406{
407}
b94cce92
HN
408static inline int register_kretprobe(struct kretprobe *rp)
409{
410 return -ENOSYS;
411}
4a296e07
MH
412static inline int register_kretprobes(struct kretprobe **rps, int num)
413{
414 return -ENOSYS;
415}
b94cce92
HN
416static inline void unregister_kretprobe(struct kretprobe *rp)
417{
418}
4a296e07
MH
419static inline void unregister_kretprobes(struct kretprobe **rps, int num)
420{
421}
b94cce92
HN
422static inline void kprobe_flush_task(struct task_struct *tk)
423{
424}
de5bd88d
MH
425static inline int disable_kprobe(struct kprobe *kp)
426{
427 return -ENOSYS;
428}
429static inline int enable_kprobe(struct kprobe *kp)
430{
431 return -ENOSYS;
432}
fab94075
BP
433
434static inline bool within_kprobe_blacklist(unsigned long addr)
435{
436 return true;
437}
b1801812 438#endif /* CONFIG_KPROBES */
8f9b1528
MH
439static inline int disable_kretprobe(struct kretprobe *rp)
440{
441 return disable_kprobe(&rp->kp);
442}
443static inline int enable_kretprobe(struct kretprobe *rp)
444{
445 return enable_kprobe(&rp->kp);
446}
8f9b1528 447
5b485629
MH
448#ifndef CONFIG_KPROBES
449static inline bool is_kprobe_insn_slot(unsigned long addr)
450{
451 return false;
452}
453#endif
454#ifndef CONFIG_OPTPROBES
455static inline bool is_kprobe_optinsn_slot(unsigned long addr)
456{
457 return false;
458}
459#endif
460
b1801812 461#endif /* _LINUX_KPROBES_H */