1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | #ifndef _LINUX_KPROBES_H |
3 | #define _LINUX_KPROBES_H |
4 | /* |
5 | * Kernel Probes (KProbes) |
6 | * |
7 | * Copyright (C) IBM Corporation, 2002, 2004 |
8 | * |
9 | * 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel |
10 | * Probes initial implementation ( includes suggestions from |
11 | * Rusty Russell). |
12 | * 2004-July Suparna Bhattacharya <suparna@in.ibm.com> added jumper probes |
13 | * interface to access function arguments. |
14 | * 2005-May Hien Nguyen <hien@us.ibm.com> and Jim Keniston |
15 | * <jkenisto@us.ibm.com> and Prasanna S Panchamukhi |
16 | * <prasanna@in.ibm.com> added function-return probes. |
17 | */ |
18 | #include <linux/compiler.h> |
19 | #include <linux/linkage.h> |
20 | #include <linux/list.h> |
21 | #include <linux/notifier.h> |
22 | #include <linux/smp.h> |
23 | #include <linux/bug.h> |
24 | #include <linux/percpu.h> |
25 | #include <linux/spinlock.h> |
26 | #include <linux/rcupdate.h> |
27 | #include <linux/mutex.h> |
28 | #include <linux/ftrace.h> |
29 | #include <linux/objpool.h> |
30 | #include <linux/rethook.h> |
31 | #include <asm/kprobes.h> |
32 | |
33 | #ifdef CONFIG_KPROBES |
34 | |
35 | /* kprobe_status settings */ |
36 | #define KPROBE_HIT_ACTIVE 0x00000001 |
37 | #define KPROBE_HIT_SS 0x00000002 |
38 | #define KPROBE_REENTER 0x00000004 |
39 | #define KPROBE_HIT_SSDONE 0x00000008 |
40 | |
41 | #else /* !CONFIG_KPROBES */ |
42 | #include <asm-generic/kprobes.h> |
43 | typedef int kprobe_opcode_t; |
44 | struct arch_specific_insn { |
45 | int dummy; |
46 | }; |
47 | #endif /* CONFIG_KPROBES */ |
48 | |
49 | struct kprobe; |
50 | struct pt_regs; |
51 | struct kretprobe; |
52 | struct kretprobe_instance; |
53 | typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *); |
54 | typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *, |
55 | unsigned long flags); |
56 | typedef int (*kretprobe_handler_t) (struct kretprobe_instance *, |
57 | struct pt_regs *); |
58 | |
59 | struct kprobe { |
60 | struct hlist_node hlist; |
61 | |
62 | /* list of kprobes for multi-handler support */ |
63 | struct list_head list; |
64 | |
65 | /*count the number of times this probe was temporarily disarmed */ |
66 | unsigned long nmissed; |
67 | |
68 | /* location of the probe point */ |
69 | kprobe_opcode_t *addr; |
70 | |
71 | /* Allow user to indicate symbol name of the probe point */ |
72 | const char *symbol_name; |
73 | |
74 | /* Offset into the symbol */ |
75 | unsigned int offset; |
76 | |
77 | /* Called before addr is executed. */ |
78 | kprobe_pre_handler_t pre_handler; |
79 | |
80 | /* Called after addr is executed, unless... */ |
81 | kprobe_post_handler_t post_handler; |
82 | |
83 | /* Saved opcode (which has been replaced with breakpoint) */ |
84 | kprobe_opcode_t opcode; |
85 | |
86 | /* copy of the original instruction */ |
87 | struct arch_specific_insn ainsn; |
88 | |
89 | /* |
90 | * Indicates various status flags. |
91 | * Protected by kprobe_mutex after this kprobe is registered. |
92 | */ |
93 | u32 flags; |
94 | }; |
95 | |
96 | /* Kprobe status flags */ |
97 | #define KPROBE_FLAG_GONE 1 /* breakpoint has already gone */ |
98 | #define KPROBE_FLAG_DISABLED 2 /* probe is temporarily disabled */ |
99 | #define KPROBE_FLAG_OPTIMIZED 4 /* |
100 | * probe is really optimized. |
101 | * NOTE: |
102 | * this flag is only for optimized_kprobe. |
103 | */ |
104 | #define KPROBE_FLAG_FTRACE 8 /* probe is using ftrace */ |
105 | #define KPROBE_FLAG_ON_FUNC_ENTRY 16 /* probe is on the function entry */ |
106 | |
107 | /* Has this kprobe gone ? */ |
108 | static inline bool kprobe_gone(struct kprobe *p) |
109 | { |
110 | return p->flags & KPROBE_FLAG_GONE; |
111 | } |
112 | |
113 | /* Is this kprobe disabled ? */ |
114 | static inline bool kprobe_disabled(struct kprobe *p) |
115 | { |
116 | return p->flags & (KPROBE_FLAG_DISABLED | KPROBE_FLAG_GONE); |
117 | } |
118 | |
119 | /* Is this kprobe really running optimized path ? */ |
120 | static inline bool kprobe_optimized(struct kprobe *p) |
121 | { |
122 | return p->flags & KPROBE_FLAG_OPTIMIZED; |
123 | } |
124 | |
125 | /* Is this kprobe uses ftrace ? */ |
126 | static inline bool kprobe_ftrace(struct kprobe *p) |
127 | { |
128 | return p->flags & KPROBE_FLAG_FTRACE; |
129 | } |
130 | |
131 | /* |
132 | * Function-return probe - |
133 | * Note: |
134 | * User needs to provide a handler function, and initialize maxactive. |
135 | * maxactive - The maximum number of instances of the probed function that |
136 | * can be active concurrently. |
137 | * nmissed - tracks the number of times the probed function's return was |
138 | * ignored, due to maxactive being too low. |
139 | * |
140 | */ |
141 | struct kretprobe_holder { |
142 | struct kretprobe *rp; |
143 | struct objpool_head pool; |
144 | }; |
145 | |
146 | struct 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 | #ifdef CONFIG_KRETPROBE_ON_RETHOOK |
154 | struct rethook *rh; |
155 | #else |
156 | struct kretprobe_holder *rph; |
157 | #endif |
158 | }; |
159 | |
160 | #define KRETPROBE_MAX_DATA_SIZE 4096 |
161 | |
162 | struct kretprobe_instance { |
163 | #ifdef CONFIG_KRETPROBE_ON_RETHOOK |
164 | struct rethook_node node; |
165 | #else |
166 | struct rcu_head rcu; |
167 | struct llist_node llist; |
168 | struct kretprobe_holder *rph; |
169 | kprobe_opcode_t *ret_addr; |
170 | void *fp; |
171 | #endif |
172 | char data[]; |
173 | }; |
174 | |
175 | struct kretprobe_blackpoint { |
176 | const char *name; |
177 | void *addr; |
178 | }; |
179 | |
180 | struct kprobe_blacklist_entry { |
181 | struct list_head list; |
182 | unsigned long start_addr; |
183 | unsigned long end_addr; |
184 | }; |
185 | |
186 | #ifdef CONFIG_KPROBES |
187 | DECLARE_PER_CPU(struct kprobe *, current_kprobe); |
188 | DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); |
189 | |
190 | extern void kprobe_busy_begin(void); |
191 | extern void kprobe_busy_end(void); |
192 | |
193 | #ifdef CONFIG_KRETPROBES |
194 | /* Check whether @p is used for implementing a trampoline. */ |
195 | extern int arch_trampoline_kprobe(struct kprobe *p); |
196 | |
197 | #ifdef CONFIG_KRETPROBE_ON_RETHOOK |
198 | static nokprobe_inline struct kretprobe *get_kretprobe(struct kretprobe_instance *ri) |
199 | { |
200 | RCU_LOCKDEP_WARN(!rcu_read_lock_any_held(), |
201 | "Kretprobe is accessed from instance under preemptive context" ); |
202 | |
203 | return (struct kretprobe *)READ_ONCE(ri->node.rethook->data); |
204 | } |
205 | static nokprobe_inline unsigned long get_kretprobe_retaddr(struct kretprobe_instance *ri) |
206 | { |
207 | return ri->node.ret_addr; |
208 | } |
209 | #else |
210 | extern void arch_prepare_kretprobe(struct kretprobe_instance *ri, |
211 | struct pt_regs *regs); |
212 | void arch_kretprobe_fixup_return(struct pt_regs *regs, |
213 | kprobe_opcode_t *correct_ret_addr); |
214 | |
215 | void __kretprobe_trampoline(void); |
216 | /* |
217 | * Since some architecture uses structured function pointer, |
218 | * use dereference_function_descriptor() to get real function address. |
219 | */ |
220 | static nokprobe_inline void *kretprobe_trampoline_addr(void) |
221 | { |
222 | return dereference_kernel_function_descriptor(__kretprobe_trampoline); |
223 | } |
224 | |
225 | /* If the trampoline handler called from a kprobe, use this version */ |
226 | unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs, |
227 | void *frame_pointer); |
228 | |
229 | static nokprobe_inline |
230 | unsigned long kretprobe_trampoline_handler(struct pt_regs *regs, |
231 | void *frame_pointer) |
232 | { |
233 | unsigned long ret; |
234 | /* |
235 | * Set a dummy kprobe for avoiding kretprobe recursion. |
236 | * Since kretprobe never runs in kprobe handler, no kprobe must |
237 | * be running at this point. |
238 | */ |
239 | kprobe_busy_begin(); |
240 | ret = __kretprobe_trampoline_handler(regs, frame_pointer); |
241 | kprobe_busy_end(); |
242 | |
243 | return ret; |
244 | } |
245 | |
246 | static nokprobe_inline struct kretprobe *get_kretprobe(struct kretprobe_instance *ri) |
247 | { |
248 | RCU_LOCKDEP_WARN(!rcu_read_lock_any_held(), |
249 | "Kretprobe is accessed from instance under preemptive context" ); |
250 | |
251 | return READ_ONCE(ri->rph->rp); |
252 | } |
253 | |
254 | static nokprobe_inline unsigned long get_kretprobe_retaddr(struct kretprobe_instance *ri) |
255 | { |
256 | return (unsigned long)ri->ret_addr; |
257 | } |
258 | #endif /* CONFIG_KRETPROBE_ON_RETHOOK */ |
259 | |
260 | #else /* !CONFIG_KRETPROBES */ |
261 | static inline void arch_prepare_kretprobe(struct kretprobe *rp, |
262 | struct pt_regs *regs) |
263 | { |
264 | } |
265 | static inline int arch_trampoline_kprobe(struct kprobe *p) |
266 | { |
267 | return 0; |
268 | } |
269 | #endif /* CONFIG_KRETPROBES */ |
270 | |
271 | /* Markers of '_kprobe_blacklist' section */ |
272 | extern unsigned long __start_kprobe_blacklist[]; |
273 | extern unsigned long __stop_kprobe_blacklist[]; |
274 | |
275 | extern struct kretprobe_blackpoint kretprobe_blacklist[]; |
276 | |
277 | #ifdef CONFIG_KPROBES_SANITY_TEST |
278 | extern int init_test_probes(void); |
279 | #else /* !CONFIG_KPROBES_SANITY_TEST */ |
280 | static inline int init_test_probes(void) |
281 | { |
282 | return 0; |
283 | } |
284 | #endif /* CONFIG_KPROBES_SANITY_TEST */ |
285 | |
286 | extern int arch_prepare_kprobe(struct kprobe *p); |
287 | extern void arch_arm_kprobe(struct kprobe *p); |
288 | extern void arch_disarm_kprobe(struct kprobe *p); |
289 | extern int arch_init_kprobes(void); |
290 | extern void kprobes_inc_nmissed_count(struct kprobe *p); |
291 | extern bool arch_within_kprobe_blacklist(unsigned long addr); |
292 | extern int arch_populate_kprobe_blacklist(void); |
293 | extern int kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset); |
294 | |
295 | extern bool within_kprobe_blacklist(unsigned long addr); |
296 | extern int kprobe_add_ksym_blacklist(unsigned long entry); |
297 | extern int kprobe_add_area_blacklist(unsigned long start, unsigned long end); |
298 | |
299 | struct kprobe_insn_cache { |
300 | struct mutex mutex; |
301 | void *(*alloc)(void); /* allocate insn page */ |
302 | void (*free)(void *); /* free insn page */ |
303 | const char *sym; /* symbol for insn pages */ |
304 | struct list_head pages; /* list of kprobe_insn_page */ |
305 | size_t insn_size; /* size of instruction slot */ |
306 | int nr_garbage; |
307 | }; |
308 | |
309 | #ifdef __ARCH_WANT_KPROBES_INSN_SLOT |
310 | extern kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c); |
311 | extern void __free_insn_slot(struct kprobe_insn_cache *c, |
312 | kprobe_opcode_t *slot, int dirty); |
313 | /* sleep-less address checking routine */ |
314 | extern bool __is_insn_slot_addr(struct kprobe_insn_cache *c, |
315 | unsigned long addr); |
316 | |
317 | #define DEFINE_INSN_CACHE_OPS(__name) \ |
318 | extern struct kprobe_insn_cache kprobe_##__name##_slots; \ |
319 | \ |
320 | static inline kprobe_opcode_t *get_##__name##_slot(void) \ |
321 | { \ |
322 | return __get_insn_slot(&kprobe_##__name##_slots); \ |
323 | } \ |
324 | \ |
325 | static inline void free_##__name##_slot(kprobe_opcode_t *slot, int dirty)\ |
326 | { \ |
327 | __free_insn_slot(&kprobe_##__name##_slots, slot, dirty); \ |
328 | } \ |
329 | \ |
330 | static inline bool is_kprobe_##__name##_slot(unsigned long addr) \ |
331 | { \ |
332 | return __is_insn_slot_addr(&kprobe_##__name##_slots, addr); \ |
333 | } |
334 | #define KPROBE_INSN_PAGE_SYM "kprobe_insn_page" |
335 | #define KPROBE_OPTINSN_PAGE_SYM "kprobe_optinsn_page" |
336 | int kprobe_cache_get_kallsym(struct kprobe_insn_cache *c, unsigned int *symnum, |
337 | unsigned long *value, char *type, char *sym); |
338 | #else /* !__ARCH_WANT_KPROBES_INSN_SLOT */ |
339 | #define DEFINE_INSN_CACHE_OPS(__name) \ |
340 | static inline bool is_kprobe_##__name##_slot(unsigned long addr) \ |
341 | { \ |
342 | return 0; \ |
343 | } |
344 | #endif |
345 | |
346 | DEFINE_INSN_CACHE_OPS(insn); |
347 | |
348 | #ifdef CONFIG_OPTPROBES |
349 | /* |
350 | * Internal structure for direct jump optimized probe |
351 | */ |
352 | struct optimized_kprobe { |
353 | struct kprobe kp; |
354 | struct list_head list; /* list for optimizing queue */ |
355 | struct arch_optimized_insn optinsn; |
356 | }; |
357 | |
358 | /* Architecture dependent functions for direct jump optimization */ |
359 | extern int arch_prepared_optinsn(struct arch_optimized_insn *optinsn); |
360 | extern int arch_check_optimized_kprobe(struct optimized_kprobe *op); |
361 | extern int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, |
362 | struct kprobe *orig); |
363 | extern void arch_remove_optimized_kprobe(struct optimized_kprobe *op); |
364 | extern void arch_optimize_kprobes(struct list_head *oplist); |
365 | extern void arch_unoptimize_kprobes(struct list_head *oplist, |
366 | struct list_head *done_list); |
367 | extern void arch_unoptimize_kprobe(struct optimized_kprobe *op); |
368 | extern int arch_within_optimized_kprobe(struct optimized_kprobe *op, |
369 | kprobe_opcode_t *addr); |
370 | |
371 | extern void opt_pre_handler(struct kprobe *p, struct pt_regs *regs); |
372 | |
373 | DEFINE_INSN_CACHE_OPS(optinsn); |
374 | |
375 | extern void wait_for_kprobe_optimizer(void); |
376 | bool optprobe_queued_unopt(struct optimized_kprobe *op); |
377 | bool kprobe_disarmed(struct kprobe *p); |
378 | #else /* !CONFIG_OPTPROBES */ |
379 | static inline void wait_for_kprobe_optimizer(void) { } |
380 | #endif /* CONFIG_OPTPROBES */ |
381 | |
382 | #ifdef CONFIG_KPROBES_ON_FTRACE |
383 | extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, |
384 | struct ftrace_ops *ops, struct ftrace_regs *fregs); |
385 | extern int arch_prepare_kprobe_ftrace(struct kprobe *p); |
386 | #else |
387 | static inline int arch_prepare_kprobe_ftrace(struct kprobe *p) |
388 | { |
389 | return -EINVAL; |
390 | } |
391 | #endif /* CONFIG_KPROBES_ON_FTRACE */ |
392 | |
393 | /* Get the kprobe at this addr (if any) - called with preemption disabled */ |
394 | struct kprobe *get_kprobe(void *addr); |
395 | |
396 | /* kprobe_running() will just return the current_kprobe on this CPU */ |
397 | static inline struct kprobe *kprobe_running(void) |
398 | { |
399 | return __this_cpu_read(current_kprobe); |
400 | } |
401 | |
402 | static inline void reset_current_kprobe(void) |
403 | { |
404 | __this_cpu_write(current_kprobe, NULL); |
405 | } |
406 | |
407 | static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void) |
408 | { |
409 | return this_cpu_ptr(&kprobe_ctlblk); |
410 | } |
411 | |
412 | kprobe_opcode_t *kprobe_lookup_name(const char *name, unsigned int offset); |
413 | kprobe_opcode_t *arch_adjust_kprobe_addr(unsigned long addr, unsigned long offset, bool *on_func_entry); |
414 | |
415 | int register_kprobe(struct kprobe *p); |
416 | void unregister_kprobe(struct kprobe *p); |
417 | int register_kprobes(struct kprobe **kps, int num); |
418 | void unregister_kprobes(struct kprobe **kps, int num); |
419 | |
420 | int register_kretprobe(struct kretprobe *rp); |
421 | void unregister_kretprobe(struct kretprobe *rp); |
422 | int register_kretprobes(struct kretprobe **rps, int num); |
423 | void unregister_kretprobes(struct kretprobe **rps, int num); |
424 | |
425 | #if defined(CONFIG_KRETPROBE_ON_RETHOOK) || !defined(CONFIG_KRETPROBES) |
426 | #define kprobe_flush_task(tk) do {} while (0) |
427 | #else |
428 | void kprobe_flush_task(struct task_struct *tk); |
429 | #endif |
430 | |
431 | void kprobe_free_init_mem(void); |
432 | |
433 | int disable_kprobe(struct kprobe *kp); |
434 | int enable_kprobe(struct kprobe *kp); |
435 | |
436 | void dump_kprobe(struct kprobe *kp); |
437 | |
438 | void *alloc_insn_page(void); |
439 | |
440 | void *alloc_optinsn_page(void); |
441 | void free_optinsn_page(void *page); |
442 | |
443 | int kprobe_get_kallsym(unsigned int symnum, unsigned long *value, char *type, |
444 | char *sym); |
445 | |
446 | int arch_kprobe_get_kallsym(unsigned int *symnum, unsigned long *value, |
447 | char *type, char *sym); |
448 | #else /* !CONFIG_KPROBES: */ |
449 | |
450 | static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) |
451 | { |
452 | return 0; |
453 | } |
454 | static inline struct kprobe *get_kprobe(void *addr) |
455 | { |
456 | return NULL; |
457 | } |
458 | static inline struct kprobe *kprobe_running(void) |
459 | { |
460 | return NULL; |
461 | } |
462 | #define kprobe_busy_begin() do {} while (0) |
463 | #define kprobe_busy_end() do {} while (0) |
464 | |
465 | static inline int register_kprobe(struct kprobe *p) |
466 | { |
467 | return -EOPNOTSUPP; |
468 | } |
469 | static inline int register_kprobes(struct kprobe **kps, int num) |
470 | { |
471 | return -EOPNOTSUPP; |
472 | } |
473 | static inline void unregister_kprobe(struct kprobe *p) |
474 | { |
475 | } |
476 | static inline void unregister_kprobes(struct kprobe **kps, int num) |
477 | { |
478 | } |
479 | static inline int register_kretprobe(struct kretprobe *rp) |
480 | { |
481 | return -EOPNOTSUPP; |
482 | } |
483 | static inline int register_kretprobes(struct kretprobe **rps, int num) |
484 | { |
485 | return -EOPNOTSUPP; |
486 | } |
487 | static inline void unregister_kretprobe(struct kretprobe *rp) |
488 | { |
489 | } |
490 | static inline void unregister_kretprobes(struct kretprobe **rps, int num) |
491 | { |
492 | } |
493 | static inline void kprobe_flush_task(struct task_struct *tk) |
494 | { |
495 | } |
496 | static inline void kprobe_free_init_mem(void) |
497 | { |
498 | } |
499 | static inline int disable_kprobe(struct kprobe *kp) |
500 | { |
501 | return -EOPNOTSUPP; |
502 | } |
503 | static inline int enable_kprobe(struct kprobe *kp) |
504 | { |
505 | return -EOPNOTSUPP; |
506 | } |
507 | |
508 | static inline bool within_kprobe_blacklist(unsigned long addr) |
509 | { |
510 | return true; |
511 | } |
512 | static inline int kprobe_get_kallsym(unsigned int symnum, unsigned long *value, |
513 | char *type, char *sym) |
514 | { |
515 | return -ERANGE; |
516 | } |
517 | #endif /* CONFIG_KPROBES */ |
518 | |
519 | static inline int disable_kretprobe(struct kretprobe *rp) |
520 | { |
521 | return disable_kprobe(kp: &rp->kp); |
522 | } |
523 | static inline int enable_kretprobe(struct kretprobe *rp) |
524 | { |
525 | return enable_kprobe(kp: &rp->kp); |
526 | } |
527 | |
528 | #ifndef CONFIG_KPROBES |
529 | static inline bool is_kprobe_insn_slot(unsigned long addr) |
530 | { |
531 | return false; |
532 | } |
533 | #endif /* !CONFIG_KPROBES */ |
534 | |
535 | #ifndef CONFIG_OPTPROBES |
536 | static inline bool is_kprobe_optinsn_slot(unsigned long addr) |
537 | { |
538 | return false; |
539 | } |
540 | #endif /* !CONFIG_OPTPROBES */ |
541 | |
542 | #ifdef CONFIG_KRETPROBES |
543 | #ifdef CONFIG_KRETPROBE_ON_RETHOOK |
544 | static nokprobe_inline bool is_kretprobe_trampoline(unsigned long addr) |
545 | { |
546 | return is_rethook_trampoline(addr); |
547 | } |
548 | |
549 | static nokprobe_inline |
550 | unsigned long kretprobe_find_ret_addr(struct task_struct *tsk, void *fp, |
551 | struct llist_node **cur) |
552 | { |
553 | return rethook_find_ret_addr(tsk, frame: (unsigned long)fp, cur); |
554 | } |
555 | #else |
556 | static nokprobe_inline bool is_kretprobe_trampoline(unsigned long addr) |
557 | { |
558 | return (void *)addr == kretprobe_trampoline_addr(); |
559 | } |
560 | |
561 | unsigned long kretprobe_find_ret_addr(struct task_struct *tsk, void *fp, |
562 | struct llist_node **cur); |
563 | #endif |
564 | #else |
565 | static nokprobe_inline bool is_kretprobe_trampoline(unsigned long addr) |
566 | { |
567 | return false; |
568 | } |
569 | |
570 | static nokprobe_inline |
571 | unsigned long kretprobe_find_ret_addr(struct task_struct *tsk, void *fp, |
572 | struct llist_node **cur) |
573 | { |
574 | return 0; |
575 | } |
576 | #endif |
577 | |
578 | /* Returns true if kprobes handled the fault */ |
579 | static nokprobe_inline bool kprobe_page_fault(struct pt_regs *regs, |
580 | unsigned int trap) |
581 | { |
582 | if (!IS_ENABLED(CONFIG_KPROBES)) |
583 | return false; |
584 | if (user_mode(regs)) |
585 | return false; |
586 | /* |
587 | * To be potentially processing a kprobe fault and to be allowed |
588 | * to call kprobe_running(), we have to be non-preemptible. |
589 | */ |
590 | if (preemptible()) |
591 | return false; |
592 | if (!kprobe_running()) |
593 | return false; |
594 | return kprobe_fault_handler(regs, trapnr: trap); |
595 | } |
596 | |
597 | #endif /* _LINUX_KPROBES_H */ |
598 | |