1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com
3  * Copyright (c) 2016 Facebook
4  */
5 #include <linux/kernel.h>
6 #include <linux/types.h>
7 #include <linux/slab.h>
8 #include <linux/bpf.h>
9 #include <linux/bpf_perf_event.h>
10 #include <linux/btf.h>
11 #include <linux/filter.h>
12 #include <linux/uaccess.h>
13 #include <linux/ctype.h>
14 #include <linux/kprobes.h>
15 #include <linux/spinlock.h>
16 #include <linux/syscalls.h>
17 #include <linux/error-injection.h>
18 #include <linux/btf_ids.h>
19 #include <linux/bpf_lsm.h>
20 #include <linux/fprobe.h>
21 #include <linux/bsearch.h>
22 #include <linux/sort.h>
23 
24 #include <net/bpf_sk_storage.h>
25 
26 #include <uapi/linux/bpf.h>
27 #include <uapi/linux/btf.h>
28 
29 #include <asm/tlb.h>
30 
31 #include "trace_probe.h"
32 #include "trace.h"
33 
34 #define CREATE_TRACE_POINTS
35 #include "bpf_trace.h"
36 
37 #define bpf_event_rcu_dereference(p)					\
38 	rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex))
39 
40 #ifdef CONFIG_MODULES
41 struct bpf_trace_module {
42 	struct module *module;
43 	struct list_head list;
44 };
45 
46 static LIST_HEAD(bpf_trace_modules);
47 static DEFINE_MUTEX(bpf_module_mutex);
48 
bpf_get_raw_tracepoint_module(const char * name)49 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
50 {
51 	struct bpf_raw_event_map *btp, *ret = NULL;
52 	struct bpf_trace_module *btm;
53 	unsigned int i;
54 
55 	mutex_lock(&bpf_module_mutex);
56 	list_for_each_entry(btm, &bpf_trace_modules, list) {
57 		for (i = 0; i < btm->module->num_bpf_raw_events; ++i) {
58 			btp = &btm->module->bpf_raw_events[i];
59 			if (!strcmp(btp->tp->name, name)) {
60 				if (try_module_get(btm->module))
61 					ret = btp;
62 				goto out;
63 			}
64 		}
65 	}
66 out:
67 	mutex_unlock(&bpf_module_mutex);
68 	return ret;
69 }
70 #else
bpf_get_raw_tracepoint_module(const char * name)71 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
72 {
73 	return NULL;
74 }
75 #endif /* CONFIG_MODULES */
76 
77 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
78 u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
79 
80 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
81 				  u64 flags, const struct btf **btf,
82 				  s32 *btf_id);
83 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx);
84 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
85 
86 /**
87  * trace_call_bpf - invoke BPF program
88  * @call: tracepoint event
89  * @ctx: opaque context pointer
90  *
91  * kprobe handlers execute BPF programs via this helper.
92  * Can be used from static tracepoints in the future.
93  *
94  * Return: BPF programs always return an integer which is interpreted by
95  * kprobe handler as:
96  * 0 - return from kprobe (event is filtered out)
97  * 1 - store kprobe event into ring buffer
98  * Other values are reserved and currently alias to 1
99  */
trace_call_bpf(struct trace_event_call * call,void * ctx)100 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
101 {
102 	unsigned int ret;
103 
104 	cant_sleep();
105 
106 	if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
107 		/*
108 		 * since some bpf program is already running on this cpu,
109 		 * don't call into another bpf program (same or different)
110 		 * and don't send kprobe event into ring-buffer,
111 		 * so return zero here
112 		 */
113 		ret = 0;
114 		goto out;
115 	}
116 
117 	/*
118 	 * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock
119 	 * to all call sites, we did a bpf_prog_array_valid() there to check
120 	 * whether call->prog_array is empty or not, which is
121 	 * a heuristic to speed up execution.
122 	 *
123 	 * If bpf_prog_array_valid() fetched prog_array was
124 	 * non-NULL, we go into trace_call_bpf() and do the actual
125 	 * proper rcu_dereference() under RCU lock.
126 	 * If it turns out that prog_array is NULL then, we bail out.
127 	 * For the opposite, if the bpf_prog_array_valid() fetched pointer
128 	 * was NULL, you'll skip the prog_array with the risk of missing
129 	 * out of events when it was updated in between this and the
130 	 * rcu_dereference() which is accepted risk.
131 	 */
132 	rcu_read_lock();
133 	ret = bpf_prog_run_array(rcu_dereference(call->prog_array),
134 				 ctx, bpf_prog_run);
135 	rcu_read_unlock();
136 
137  out:
138 	__this_cpu_dec(bpf_prog_active);
139 
140 	return ret;
141 }
142 
143 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
BPF_CALL_2(bpf_override_return,struct pt_regs *,regs,unsigned long,rc)144 BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
145 {
146 	regs_set_return_value(regs, rc);
147 	override_function_with_return(regs);
148 	return 0;
149 }
150 
151 static const struct bpf_func_proto bpf_override_return_proto = {
152 	.func		= bpf_override_return,
153 	.gpl_only	= true,
154 	.ret_type	= RET_INTEGER,
155 	.arg1_type	= ARG_PTR_TO_CTX,
156 	.arg2_type	= ARG_ANYTHING,
157 };
158 #endif
159 
160 static __always_inline int
bpf_probe_read_user_common(void * dst,u32 size,const void __user * unsafe_ptr)161 bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
162 {
163 	int ret;
164 
165 	ret = copy_from_user_nofault(dst, unsafe_ptr, size);
166 	if (unlikely(ret < 0))
167 		memset(dst, 0, size);
168 	return ret;
169 }
170 
BPF_CALL_3(bpf_probe_read_user,void *,dst,u32,size,const void __user *,unsafe_ptr)171 BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
172 	   const void __user *, unsafe_ptr)
173 {
174 	return bpf_probe_read_user_common(dst, size, unsafe_ptr);
175 }
176 
177 const struct bpf_func_proto bpf_probe_read_user_proto = {
178 	.func		= bpf_probe_read_user,
179 	.gpl_only	= true,
180 	.ret_type	= RET_INTEGER,
181 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
182 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
183 	.arg3_type	= ARG_ANYTHING,
184 };
185 
186 static __always_inline int
bpf_probe_read_user_str_common(void * dst,u32 size,const void __user * unsafe_ptr)187 bpf_probe_read_user_str_common(void *dst, u32 size,
188 			       const void __user *unsafe_ptr)
189 {
190 	int ret;
191 
192 	/*
193 	 * NB: We rely on strncpy_from_user() not copying junk past the NUL
194 	 * terminator into `dst`.
195 	 *
196 	 * strncpy_from_user() does long-sized strides in the fast path. If the
197 	 * strncpy does not mask out the bytes after the NUL in `unsafe_ptr`,
198 	 * then there could be junk after the NUL in `dst`. If user takes `dst`
199 	 * and keys a hash map with it, then semantically identical strings can
200 	 * occupy multiple entries in the map.
201 	 */
202 	ret = strncpy_from_user_nofault(dst, unsafe_ptr, size);
203 	if (unlikely(ret < 0))
204 		memset(dst, 0, size);
205 	return ret;
206 }
207 
BPF_CALL_3(bpf_probe_read_user_str,void *,dst,u32,size,const void __user *,unsafe_ptr)208 BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
209 	   const void __user *, unsafe_ptr)
210 {
211 	return bpf_probe_read_user_str_common(dst, size, unsafe_ptr);
212 }
213 
214 const struct bpf_func_proto bpf_probe_read_user_str_proto = {
215 	.func		= bpf_probe_read_user_str,
216 	.gpl_only	= true,
217 	.ret_type	= RET_INTEGER,
218 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
219 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
220 	.arg3_type	= ARG_ANYTHING,
221 };
222 
223 static __always_inline int
bpf_probe_read_kernel_common(void * dst,u32 size,const void * unsafe_ptr)224 bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
225 {
226 	int ret;
227 
228 	ret = copy_from_kernel_nofault(dst, unsafe_ptr, size);
229 	if (unlikely(ret < 0))
230 		memset(dst, 0, size);
231 	return ret;
232 }
233 
BPF_CALL_3(bpf_probe_read_kernel,void *,dst,u32,size,const void *,unsafe_ptr)234 BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
235 	   const void *, unsafe_ptr)
236 {
237 	return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
238 }
239 
240 const struct bpf_func_proto bpf_probe_read_kernel_proto = {
241 	.func		= bpf_probe_read_kernel,
242 	.gpl_only	= true,
243 	.ret_type	= RET_INTEGER,
244 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
245 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
246 	.arg3_type	= ARG_ANYTHING,
247 };
248 
249 static __always_inline int
bpf_probe_read_kernel_str_common(void * dst,u32 size,const void * unsafe_ptr)250 bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
251 {
252 	int ret;
253 
254 	/*
255 	 * The strncpy_from_kernel_nofault() call will likely not fill the
256 	 * entire buffer, but that's okay in this circumstance as we're probing
257 	 * arbitrary memory anyway similar to bpf_probe_read_*() and might
258 	 * as well probe the stack. Thus, memory is explicitly cleared
259 	 * only in error case, so that improper users ignoring return
260 	 * code altogether don't copy garbage; otherwise length of string
261 	 * is returned that can be used for bpf_perf_event_output() et al.
262 	 */
263 	ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
264 	if (unlikely(ret < 0))
265 		memset(dst, 0, size);
266 	return ret;
267 }
268 
BPF_CALL_3(bpf_probe_read_kernel_str,void *,dst,u32,size,const void *,unsafe_ptr)269 BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
270 	   const void *, unsafe_ptr)
271 {
272 	return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
273 }
274 
275 const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
276 	.func		= bpf_probe_read_kernel_str,
277 	.gpl_only	= true,
278 	.ret_type	= RET_INTEGER,
279 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
280 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
281 	.arg3_type	= ARG_ANYTHING,
282 };
283 
284 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
BPF_CALL_3(bpf_probe_read_compat,void *,dst,u32,size,const void *,unsafe_ptr)285 BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
286 	   const void *, unsafe_ptr)
287 {
288 	if ((unsigned long)unsafe_ptr < TASK_SIZE) {
289 		return bpf_probe_read_user_common(dst, size,
290 				(__force void __user *)unsafe_ptr);
291 	}
292 	return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
293 }
294 
295 static const struct bpf_func_proto bpf_probe_read_compat_proto = {
296 	.func		= bpf_probe_read_compat,
297 	.gpl_only	= true,
298 	.ret_type	= RET_INTEGER,
299 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
300 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
301 	.arg3_type	= ARG_ANYTHING,
302 };
303 
BPF_CALL_3(bpf_probe_read_compat_str,void *,dst,u32,size,const void *,unsafe_ptr)304 BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
305 	   const void *, unsafe_ptr)
306 {
307 	if ((unsigned long)unsafe_ptr < TASK_SIZE) {
308 		return bpf_probe_read_user_str_common(dst, size,
309 				(__force void __user *)unsafe_ptr);
310 	}
311 	return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
312 }
313 
314 static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
315 	.func		= bpf_probe_read_compat_str,
316 	.gpl_only	= true,
317 	.ret_type	= RET_INTEGER,
318 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
319 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
320 	.arg3_type	= ARG_ANYTHING,
321 };
322 #endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */
323 
BPF_CALL_3(bpf_probe_write_user,void __user *,unsafe_ptr,const void *,src,u32,size)324 BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
325 	   u32, size)
326 {
327 	/*
328 	 * Ensure we're in user context which is safe for the helper to
329 	 * run. This helper has no business in a kthread.
330 	 *
331 	 * access_ok() should prevent writing to non-user memory, but in
332 	 * some situations (nommu, temporary switch, etc) access_ok() does
333 	 * not provide enough validation, hence the check on KERNEL_DS.
334 	 *
335 	 * nmi_uaccess_okay() ensures the probe is not run in an interim
336 	 * state, when the task or mm are switched. This is specifically
337 	 * required to prevent the use of temporary mm.
338 	 */
339 
340 	if (unlikely(in_interrupt() ||
341 		     current->flags & (PF_KTHREAD | PF_EXITING)))
342 		return -EPERM;
343 	if (unlikely(!nmi_uaccess_okay()))
344 		return -EPERM;
345 
346 	return copy_to_user_nofault(unsafe_ptr, src, size);
347 }
348 
349 static const struct bpf_func_proto bpf_probe_write_user_proto = {
350 	.func		= bpf_probe_write_user,
351 	.gpl_only	= true,
352 	.ret_type	= RET_INTEGER,
353 	.arg1_type	= ARG_ANYTHING,
354 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
355 	.arg3_type	= ARG_CONST_SIZE,
356 };
357 
bpf_get_probe_write_proto(void)358 static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
359 {
360 	if (!capable(CAP_SYS_ADMIN))
361 		return NULL;
362 
363 	pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!",
364 			    current->comm, task_pid_nr(current));
365 
366 	return &bpf_probe_write_user_proto;
367 }
368 
369 static DEFINE_RAW_SPINLOCK(trace_printk_lock);
370 
371 #define MAX_TRACE_PRINTK_VARARGS	3
372 #define BPF_TRACE_PRINTK_SIZE		1024
373 
BPF_CALL_5(bpf_trace_printk,char *,fmt,u32,fmt_size,u64,arg1,u64,arg2,u64,arg3)374 BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
375 	   u64, arg2, u64, arg3)
376 {
377 	u64 args[MAX_TRACE_PRINTK_VARARGS] = { arg1, arg2, arg3 };
378 	u32 *bin_args;
379 	static char buf[BPF_TRACE_PRINTK_SIZE];
380 	unsigned long flags;
381 	int ret;
382 
383 	ret = bpf_bprintf_prepare(fmt, fmt_size, args, &bin_args,
384 				  MAX_TRACE_PRINTK_VARARGS);
385 	if (ret < 0)
386 		return ret;
387 
388 	raw_spin_lock_irqsave(&trace_printk_lock, flags);
389 	ret = bstr_printf(buf, sizeof(buf), fmt, bin_args);
390 
391 	trace_bpf_trace_printk(buf);
392 	raw_spin_unlock_irqrestore(&trace_printk_lock, flags);
393 
394 	bpf_bprintf_cleanup();
395 
396 	return ret;
397 }
398 
399 static const struct bpf_func_proto bpf_trace_printk_proto = {
400 	.func		= bpf_trace_printk,
401 	.gpl_only	= true,
402 	.ret_type	= RET_INTEGER,
403 	.arg1_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
404 	.arg2_type	= ARG_CONST_SIZE,
405 };
406 
__set_printk_clr_event(void)407 static void __set_printk_clr_event(void)
408 {
409 	/*
410 	 * This program might be calling bpf_trace_printk,
411 	 * so enable the associated bpf_trace/bpf_trace_printk event.
412 	 * Repeat this each time as it is possible a user has
413 	 * disabled bpf_trace_printk events.  By loading a program
414 	 * calling bpf_trace_printk() however the user has expressed
415 	 * the intent to see such events.
416 	 */
417 	if (trace_set_clr_event("bpf_trace", "bpf_trace_printk", 1))
418 		pr_warn_ratelimited("could not enable bpf_trace_printk events");
419 }
420 
bpf_get_trace_printk_proto(void)421 const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
422 {
423 	__set_printk_clr_event();
424 	return &bpf_trace_printk_proto;
425 }
426 
BPF_CALL_4(bpf_trace_vprintk,char *,fmt,u32,fmt_size,const void *,data,u32,data_len)427 BPF_CALL_4(bpf_trace_vprintk, char *, fmt, u32, fmt_size, const void *, data,
428 	   u32, data_len)
429 {
430 	static char buf[BPF_TRACE_PRINTK_SIZE];
431 	unsigned long flags;
432 	int ret, num_args;
433 	u32 *bin_args;
434 
435 	if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
436 	    (data_len && !data))
437 		return -EINVAL;
438 	num_args = data_len / 8;
439 
440 	ret = bpf_bprintf_prepare(fmt, fmt_size, data, &bin_args, num_args);
441 	if (ret < 0)
442 		return ret;
443 
444 	raw_spin_lock_irqsave(&trace_printk_lock, flags);
445 	ret = bstr_printf(buf, sizeof(buf), fmt, bin_args);
446 
447 	trace_bpf_trace_printk(buf);
448 	raw_spin_unlock_irqrestore(&trace_printk_lock, flags);
449 
450 	bpf_bprintf_cleanup();
451 
452 	return ret;
453 }
454 
455 static const struct bpf_func_proto bpf_trace_vprintk_proto = {
456 	.func		= bpf_trace_vprintk,
457 	.gpl_only	= true,
458 	.ret_type	= RET_INTEGER,
459 	.arg1_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
460 	.arg2_type	= ARG_CONST_SIZE,
461 	.arg3_type	= ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
462 	.arg4_type	= ARG_CONST_SIZE_OR_ZERO,
463 };
464 
bpf_get_trace_vprintk_proto(void)465 const struct bpf_func_proto *bpf_get_trace_vprintk_proto(void)
466 {
467 	__set_printk_clr_event();
468 	return &bpf_trace_vprintk_proto;
469 }
470 
BPF_CALL_5(bpf_seq_printf,struct seq_file *,m,char *,fmt,u32,fmt_size,const void *,data,u32,data_len)471 BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
472 	   const void *, data, u32, data_len)
473 {
474 	int err, num_args;
475 	u32 *bin_args;
476 
477 	if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
478 	    (data_len && !data))
479 		return -EINVAL;
480 	num_args = data_len / 8;
481 
482 	err = bpf_bprintf_prepare(fmt, fmt_size, data, &bin_args, num_args);
483 	if (err < 0)
484 		return err;
485 
486 	seq_bprintf(m, fmt, bin_args);
487 
488 	bpf_bprintf_cleanup();
489 
490 	return seq_has_overflowed(m) ? -EOVERFLOW : 0;
491 }
492 
493 BTF_ID_LIST_SINGLE(btf_seq_file_ids, struct, seq_file)
494 
495 static const struct bpf_func_proto bpf_seq_printf_proto = {
496 	.func		= bpf_seq_printf,
497 	.gpl_only	= true,
498 	.ret_type	= RET_INTEGER,
499 	.arg1_type	= ARG_PTR_TO_BTF_ID,
500 	.arg1_btf_id	= &btf_seq_file_ids[0],
501 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
502 	.arg3_type	= ARG_CONST_SIZE,
503 	.arg4_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
504 	.arg5_type      = ARG_CONST_SIZE_OR_ZERO,
505 };
506 
BPF_CALL_3(bpf_seq_write,struct seq_file *,m,const void *,data,u32,len)507 BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len)
508 {
509 	return seq_write(m, data, len) ? -EOVERFLOW : 0;
510 }
511 
512 static const struct bpf_func_proto bpf_seq_write_proto = {
513 	.func		= bpf_seq_write,
514 	.gpl_only	= true,
515 	.ret_type	= RET_INTEGER,
516 	.arg1_type	= ARG_PTR_TO_BTF_ID,
517 	.arg1_btf_id	= &btf_seq_file_ids[0],
518 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
519 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
520 };
521 
BPF_CALL_4(bpf_seq_printf_btf,struct seq_file *,m,struct btf_ptr *,ptr,u32,btf_ptr_size,u64,flags)522 BPF_CALL_4(bpf_seq_printf_btf, struct seq_file *, m, struct btf_ptr *, ptr,
523 	   u32, btf_ptr_size, u64, flags)
524 {
525 	const struct btf *btf;
526 	s32 btf_id;
527 	int ret;
528 
529 	ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
530 	if (ret)
531 		return ret;
532 
533 	return btf_type_seq_show_flags(btf, btf_id, ptr->ptr, m, flags);
534 }
535 
536 static const struct bpf_func_proto bpf_seq_printf_btf_proto = {
537 	.func		= bpf_seq_printf_btf,
538 	.gpl_only	= true,
539 	.ret_type	= RET_INTEGER,
540 	.arg1_type	= ARG_PTR_TO_BTF_ID,
541 	.arg1_btf_id	= &btf_seq_file_ids[0],
542 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
543 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
544 	.arg4_type	= ARG_ANYTHING,
545 };
546 
547 static __always_inline int
get_map_perf_counter(struct bpf_map * map,u64 flags,u64 * value,u64 * enabled,u64 * running)548 get_map_perf_counter(struct bpf_map *map, u64 flags,
549 		     u64 *value, u64 *enabled, u64 *running)
550 {
551 	struct bpf_array *array = container_of(map, struct bpf_array, map);
552 	unsigned int cpu = smp_processor_id();
553 	u64 index = flags & BPF_F_INDEX_MASK;
554 	struct bpf_event_entry *ee;
555 
556 	if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
557 		return -EINVAL;
558 	if (index == BPF_F_CURRENT_CPU)
559 		index = cpu;
560 	if (unlikely(index >= array->map.max_entries))
561 		return -E2BIG;
562 
563 	ee = READ_ONCE(array->ptrs[index]);
564 	if (!ee)
565 		return -ENOENT;
566 
567 	return perf_event_read_local(ee->event, value, enabled, running);
568 }
569 
BPF_CALL_2(bpf_perf_event_read,struct bpf_map *,map,u64,flags)570 BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
571 {
572 	u64 value = 0;
573 	int err;
574 
575 	err = get_map_perf_counter(map, flags, &value, NULL, NULL);
576 	/*
577 	 * this api is ugly since we miss [-22..-2] range of valid
578 	 * counter values, but that's uapi
579 	 */
580 	if (err)
581 		return err;
582 	return value;
583 }
584 
585 static const struct bpf_func_proto bpf_perf_event_read_proto = {
586 	.func		= bpf_perf_event_read,
587 	.gpl_only	= true,
588 	.ret_type	= RET_INTEGER,
589 	.arg1_type	= ARG_CONST_MAP_PTR,
590 	.arg2_type	= ARG_ANYTHING,
591 };
592 
BPF_CALL_4(bpf_perf_event_read_value,struct bpf_map *,map,u64,flags,struct bpf_perf_event_value *,buf,u32,size)593 BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
594 	   struct bpf_perf_event_value *, buf, u32, size)
595 {
596 	int err = -EINVAL;
597 
598 	if (unlikely(size != sizeof(struct bpf_perf_event_value)))
599 		goto clear;
600 	err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
601 				   &buf->running);
602 	if (unlikely(err))
603 		goto clear;
604 	return 0;
605 clear:
606 	memset(buf, 0, size);
607 	return err;
608 }
609 
610 static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
611 	.func		= bpf_perf_event_read_value,
612 	.gpl_only	= true,
613 	.ret_type	= RET_INTEGER,
614 	.arg1_type	= ARG_CONST_MAP_PTR,
615 	.arg2_type	= ARG_ANYTHING,
616 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
617 	.arg4_type	= ARG_CONST_SIZE,
618 };
619 
620 static __always_inline u64
__bpf_perf_event_output(struct pt_regs * regs,struct bpf_map * map,u64 flags,struct perf_sample_data * sd)621 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
622 			u64 flags, struct perf_sample_data *sd)
623 {
624 	struct bpf_array *array = container_of(map, struct bpf_array, map);
625 	unsigned int cpu = smp_processor_id();
626 	u64 index = flags & BPF_F_INDEX_MASK;
627 	struct bpf_event_entry *ee;
628 	struct perf_event *event;
629 
630 	if (index == BPF_F_CURRENT_CPU)
631 		index = cpu;
632 	if (unlikely(index >= array->map.max_entries))
633 		return -E2BIG;
634 
635 	ee = READ_ONCE(array->ptrs[index]);
636 	if (!ee)
637 		return -ENOENT;
638 
639 	event = ee->event;
640 	if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE ||
641 		     event->attr.config != PERF_COUNT_SW_BPF_OUTPUT))
642 		return -EINVAL;
643 
644 	if (unlikely(event->oncpu != cpu))
645 		return -EOPNOTSUPP;
646 
647 	return perf_event_output(event, sd, regs);
648 }
649 
650 /*
651  * Support executing tracepoints in normal, irq, and nmi context that each call
652  * bpf_perf_event_output
653  */
654 struct bpf_trace_sample_data {
655 	struct perf_sample_data sds[3];
656 };
657 
658 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds);
659 static DEFINE_PER_CPU(int, bpf_trace_nest_level);
BPF_CALL_5(bpf_perf_event_output,struct pt_regs *,regs,struct bpf_map *,map,u64,flags,void *,data,u64,size)660 BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
661 	   u64, flags, void *, data, u64, size)
662 {
663 	struct bpf_trace_sample_data *sds = this_cpu_ptr(&bpf_trace_sds);
664 	int nest_level = this_cpu_inc_return(bpf_trace_nest_level);
665 	struct perf_raw_record raw = {
666 		.frag = {
667 			.size = size,
668 			.data = data,
669 		},
670 	};
671 	struct perf_sample_data *sd;
672 	int err;
673 
674 	if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) {
675 		err = -EBUSY;
676 		goto out;
677 	}
678 
679 	sd = &sds->sds[nest_level - 1];
680 
681 	if (unlikely(flags & ~(BPF_F_INDEX_MASK))) {
682 		err = -EINVAL;
683 		goto out;
684 	}
685 
686 	perf_sample_data_init(sd, 0, 0);
687 	sd->raw = &raw;
688 
689 	err = __bpf_perf_event_output(regs, map, flags, sd);
690 
691 out:
692 	this_cpu_dec(bpf_trace_nest_level);
693 	return err;
694 }
695 
696 static const struct bpf_func_proto bpf_perf_event_output_proto = {
697 	.func		= bpf_perf_event_output,
698 	.gpl_only	= true,
699 	.ret_type	= RET_INTEGER,
700 	.arg1_type	= ARG_PTR_TO_CTX,
701 	.arg2_type	= ARG_CONST_MAP_PTR,
702 	.arg3_type	= ARG_ANYTHING,
703 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
704 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
705 };
706 
707 static DEFINE_PER_CPU(int, bpf_event_output_nest_level);
708 struct bpf_nested_pt_regs {
709 	struct pt_regs regs[3];
710 };
711 static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs);
712 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds);
713 
bpf_event_output(struct bpf_map * map,u64 flags,void * meta,u64 meta_size,void * ctx,u64 ctx_size,bpf_ctx_copy_t ctx_copy)714 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
715 		     void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
716 {
717 	int nest_level = this_cpu_inc_return(bpf_event_output_nest_level);
718 	struct perf_raw_frag frag = {
719 		.copy		= ctx_copy,
720 		.size		= ctx_size,
721 		.data		= ctx,
722 	};
723 	struct perf_raw_record raw = {
724 		.frag = {
725 			{
726 				.next	= ctx_size ? &frag : NULL,
727 			},
728 			.size	= meta_size,
729 			.data	= meta,
730 		},
731 	};
732 	struct perf_sample_data *sd;
733 	struct pt_regs *regs;
734 	u64 ret;
735 
736 	if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) {
737 		ret = -EBUSY;
738 		goto out;
739 	}
740 	sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]);
741 	regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]);
742 
743 	perf_fetch_caller_regs(regs);
744 	perf_sample_data_init(sd, 0, 0);
745 	sd->raw = &raw;
746 
747 	ret = __bpf_perf_event_output(regs, map, flags, sd);
748 out:
749 	this_cpu_dec(bpf_event_output_nest_level);
750 	return ret;
751 }
752 
BPF_CALL_0(bpf_get_current_task)753 BPF_CALL_0(bpf_get_current_task)
754 {
755 	return (long) current;
756 }
757 
758 const struct bpf_func_proto bpf_get_current_task_proto = {
759 	.func		= bpf_get_current_task,
760 	.gpl_only	= true,
761 	.ret_type	= RET_INTEGER,
762 };
763 
BPF_CALL_0(bpf_get_current_task_btf)764 BPF_CALL_0(bpf_get_current_task_btf)
765 {
766 	return (unsigned long) current;
767 }
768 
769 const struct bpf_func_proto bpf_get_current_task_btf_proto = {
770 	.func		= bpf_get_current_task_btf,
771 	.gpl_only	= true,
772 	.ret_type	= RET_PTR_TO_BTF_ID,
773 	.ret_btf_id	= &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
774 };
775 
BPF_CALL_1(bpf_task_pt_regs,struct task_struct *,task)776 BPF_CALL_1(bpf_task_pt_regs, struct task_struct *, task)
777 {
778 	return (unsigned long) task_pt_regs(task);
779 }
780 
781 BTF_ID_LIST(bpf_task_pt_regs_ids)
782 BTF_ID(struct, pt_regs)
783 
784 const struct bpf_func_proto bpf_task_pt_regs_proto = {
785 	.func		= bpf_task_pt_regs,
786 	.gpl_only	= true,
787 	.arg1_type	= ARG_PTR_TO_BTF_ID,
788 	.arg1_btf_id	= &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
789 	.ret_type	= RET_PTR_TO_BTF_ID,
790 	.ret_btf_id	= &bpf_task_pt_regs_ids[0],
791 };
792 
BPF_CALL_2(bpf_current_task_under_cgroup,struct bpf_map *,map,u32,idx)793 BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
794 {
795 	struct bpf_array *array = container_of(map, struct bpf_array, map);
796 	struct cgroup *cgrp;
797 
798 	if (unlikely(idx >= array->map.max_entries))
799 		return -E2BIG;
800 
801 	cgrp = READ_ONCE(array->ptrs[idx]);
802 	if (unlikely(!cgrp))
803 		return -EAGAIN;
804 
805 	return task_under_cgroup_hierarchy(current, cgrp);
806 }
807 
808 static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = {
809 	.func           = bpf_current_task_under_cgroup,
810 	.gpl_only       = false,
811 	.ret_type       = RET_INTEGER,
812 	.arg1_type      = ARG_CONST_MAP_PTR,
813 	.arg2_type      = ARG_ANYTHING,
814 };
815 
816 struct send_signal_irq_work {
817 	struct irq_work irq_work;
818 	struct task_struct *task;
819 	u32 sig;
820 	enum pid_type type;
821 };
822 
823 static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
824 
do_bpf_send_signal(struct irq_work * entry)825 static void do_bpf_send_signal(struct irq_work *entry)
826 {
827 	struct send_signal_irq_work *work;
828 
829 	work = container_of(entry, struct send_signal_irq_work, irq_work);
830 	group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
831 }
832 
bpf_send_signal_common(u32 sig,enum pid_type type)833 static int bpf_send_signal_common(u32 sig, enum pid_type type)
834 {
835 	struct send_signal_irq_work *work = NULL;
836 
837 	/* Similar to bpf_probe_write_user, task needs to be
838 	 * in a sound condition and kernel memory access be
839 	 * permitted in order to send signal to the current
840 	 * task.
841 	 */
842 	if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
843 		return -EPERM;
844 	if (unlikely(!nmi_uaccess_okay()))
845 		return -EPERM;
846 
847 	if (irqs_disabled()) {
848 		/* Do an early check on signal validity. Otherwise,
849 		 * the error is lost in deferred irq_work.
850 		 */
851 		if (unlikely(!valid_signal(sig)))
852 			return -EINVAL;
853 
854 		work = this_cpu_ptr(&send_signal_work);
855 		if (irq_work_is_busy(&work->irq_work))
856 			return -EBUSY;
857 
858 		/* Add the current task, which is the target of sending signal,
859 		 * to the irq_work. The current task may change when queued
860 		 * irq works get executed.
861 		 */
862 		work->task = current;
863 		work->sig = sig;
864 		work->type = type;
865 		irq_work_queue(&work->irq_work);
866 		return 0;
867 	}
868 
869 	return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
870 }
871 
BPF_CALL_1(bpf_send_signal,u32,sig)872 BPF_CALL_1(bpf_send_signal, u32, sig)
873 {
874 	return bpf_send_signal_common(sig, PIDTYPE_TGID);
875 }
876 
877 static const struct bpf_func_proto bpf_send_signal_proto = {
878 	.func		= bpf_send_signal,
879 	.gpl_only	= false,
880 	.ret_type	= RET_INTEGER,
881 	.arg1_type	= ARG_ANYTHING,
882 };
883 
BPF_CALL_1(bpf_send_signal_thread,u32,sig)884 BPF_CALL_1(bpf_send_signal_thread, u32, sig)
885 {
886 	return bpf_send_signal_common(sig, PIDTYPE_PID);
887 }
888 
889 static const struct bpf_func_proto bpf_send_signal_thread_proto = {
890 	.func		= bpf_send_signal_thread,
891 	.gpl_only	= false,
892 	.ret_type	= RET_INTEGER,
893 	.arg1_type	= ARG_ANYTHING,
894 };
895 
BPF_CALL_3(bpf_d_path,struct path *,path,char *,buf,u32,sz)896 BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz)
897 {
898 	long len;
899 	char *p;
900 
901 	if (!sz)
902 		return 0;
903 
904 	p = d_path(path, buf, sz);
905 	if (IS_ERR(p)) {
906 		len = PTR_ERR(p);
907 	} else {
908 		len = buf + sz - p;
909 		memmove(buf, p, len);
910 	}
911 
912 	return len;
913 }
914 
915 BTF_SET_START(btf_allowlist_d_path)
916 #ifdef CONFIG_SECURITY
BTF_ID(func,security_file_permission)917 BTF_ID(func, security_file_permission)
918 BTF_ID(func, security_inode_getattr)
919 BTF_ID(func, security_file_open)
920 #endif
921 #ifdef CONFIG_SECURITY_PATH
922 BTF_ID(func, security_path_truncate)
923 #endif
924 BTF_ID(func, vfs_truncate)
925 BTF_ID(func, vfs_fallocate)
926 BTF_ID(func, dentry_open)
927 BTF_ID(func, vfs_getattr)
928 BTF_ID(func, filp_close)
929 BTF_SET_END(btf_allowlist_d_path)
930 
931 static bool bpf_d_path_allowed(const struct bpf_prog *prog)
932 {
933 	if (prog->type == BPF_PROG_TYPE_TRACING &&
934 	    prog->expected_attach_type == BPF_TRACE_ITER)
935 		return true;
936 
937 	if (prog->type == BPF_PROG_TYPE_LSM)
938 		return bpf_lsm_is_sleepable_hook(prog->aux->attach_btf_id);
939 
940 	return btf_id_set_contains(&btf_allowlist_d_path,
941 				   prog->aux->attach_btf_id);
942 }
943 
944 BTF_ID_LIST_SINGLE(bpf_d_path_btf_ids, struct, path)
945 
946 static const struct bpf_func_proto bpf_d_path_proto = {
947 	.func		= bpf_d_path,
948 	.gpl_only	= false,
949 	.ret_type	= RET_INTEGER,
950 	.arg1_type	= ARG_PTR_TO_BTF_ID,
951 	.arg1_btf_id	= &bpf_d_path_btf_ids[0],
952 	.arg2_type	= ARG_PTR_TO_MEM,
953 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
954 	.allowed	= bpf_d_path_allowed,
955 };
956 
957 #define BTF_F_ALL	(BTF_F_COMPACT  | BTF_F_NONAME | \
958 			 BTF_F_PTR_RAW | BTF_F_ZERO)
959 
bpf_btf_printf_prepare(struct btf_ptr * ptr,u32 btf_ptr_size,u64 flags,const struct btf ** btf,s32 * btf_id)960 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
961 				  u64 flags, const struct btf **btf,
962 				  s32 *btf_id)
963 {
964 	const struct btf_type *t;
965 
966 	if (unlikely(flags & ~(BTF_F_ALL)))
967 		return -EINVAL;
968 
969 	if (btf_ptr_size != sizeof(struct btf_ptr))
970 		return -EINVAL;
971 
972 	*btf = bpf_get_btf_vmlinux();
973 
974 	if (IS_ERR_OR_NULL(*btf))
975 		return IS_ERR(*btf) ? PTR_ERR(*btf) : -EINVAL;
976 
977 	if (ptr->type_id > 0)
978 		*btf_id = ptr->type_id;
979 	else
980 		return -EINVAL;
981 
982 	if (*btf_id > 0)
983 		t = btf_type_by_id(*btf, *btf_id);
984 	if (*btf_id <= 0 || !t)
985 		return -ENOENT;
986 
987 	return 0;
988 }
989 
BPF_CALL_5(bpf_snprintf_btf,char *,str,u32,str_size,struct btf_ptr *,ptr,u32,btf_ptr_size,u64,flags)990 BPF_CALL_5(bpf_snprintf_btf, char *, str, u32, str_size, struct btf_ptr *, ptr,
991 	   u32, btf_ptr_size, u64, flags)
992 {
993 	const struct btf *btf;
994 	s32 btf_id;
995 	int ret;
996 
997 	ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
998 	if (ret)
999 		return ret;
1000 
1001 	return btf_type_snprintf_show(btf, btf_id, ptr->ptr, str, str_size,
1002 				      flags);
1003 }
1004 
1005 const struct bpf_func_proto bpf_snprintf_btf_proto = {
1006 	.func		= bpf_snprintf_btf,
1007 	.gpl_only	= false,
1008 	.ret_type	= RET_INTEGER,
1009 	.arg1_type	= ARG_PTR_TO_MEM,
1010 	.arg2_type	= ARG_CONST_SIZE,
1011 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1012 	.arg4_type	= ARG_CONST_SIZE,
1013 	.arg5_type	= ARG_ANYTHING,
1014 };
1015 
BPF_CALL_1(bpf_get_func_ip_tracing,void *,ctx)1016 BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx)
1017 {
1018 	/* This helper call is inlined by verifier. */
1019 	return ((u64 *)ctx)[-2];
1020 }
1021 
1022 static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = {
1023 	.func		= bpf_get_func_ip_tracing,
1024 	.gpl_only	= true,
1025 	.ret_type	= RET_INTEGER,
1026 	.arg1_type	= ARG_PTR_TO_CTX,
1027 };
1028 
BPF_CALL_1(bpf_get_func_ip_kprobe,struct pt_regs *,regs)1029 BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs)
1030 {
1031 	struct kprobe *kp = kprobe_running();
1032 
1033 	return kp ? (uintptr_t)kp->addr : 0;
1034 }
1035 
1036 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe = {
1037 	.func		= bpf_get_func_ip_kprobe,
1038 	.gpl_only	= true,
1039 	.ret_type	= RET_INTEGER,
1040 	.arg1_type	= ARG_PTR_TO_CTX,
1041 };
1042 
BPF_CALL_1(bpf_get_func_ip_kprobe_multi,struct pt_regs *,regs)1043 BPF_CALL_1(bpf_get_func_ip_kprobe_multi, struct pt_regs *, regs)
1044 {
1045 	return bpf_kprobe_multi_entry_ip(current->bpf_ctx);
1046 }
1047 
1048 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe_multi = {
1049 	.func		= bpf_get_func_ip_kprobe_multi,
1050 	.gpl_only	= false,
1051 	.ret_type	= RET_INTEGER,
1052 	.arg1_type	= ARG_PTR_TO_CTX,
1053 };
1054 
BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi,struct pt_regs *,regs)1055 BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi, struct pt_regs *, regs)
1056 {
1057 	return bpf_kprobe_multi_cookie(current->bpf_ctx);
1058 }
1059 
1060 static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = {
1061 	.func		= bpf_get_attach_cookie_kprobe_multi,
1062 	.gpl_only	= false,
1063 	.ret_type	= RET_INTEGER,
1064 	.arg1_type	= ARG_PTR_TO_CTX,
1065 };
1066 
BPF_CALL_1(bpf_get_attach_cookie_trace,void *,ctx)1067 BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx)
1068 {
1069 	struct bpf_trace_run_ctx *run_ctx;
1070 
1071 	run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1072 	return run_ctx->bpf_cookie;
1073 }
1074 
1075 static const struct bpf_func_proto bpf_get_attach_cookie_proto_trace = {
1076 	.func		= bpf_get_attach_cookie_trace,
1077 	.gpl_only	= false,
1078 	.ret_type	= RET_INTEGER,
1079 	.arg1_type	= ARG_PTR_TO_CTX,
1080 };
1081 
BPF_CALL_1(bpf_get_attach_cookie_pe,struct bpf_perf_event_data_kern *,ctx)1082 BPF_CALL_1(bpf_get_attach_cookie_pe, struct bpf_perf_event_data_kern *, ctx)
1083 {
1084 	return ctx->event->bpf_cookie;
1085 }
1086 
1087 static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = {
1088 	.func		= bpf_get_attach_cookie_pe,
1089 	.gpl_only	= false,
1090 	.ret_type	= RET_INTEGER,
1091 	.arg1_type	= ARG_PTR_TO_CTX,
1092 };
1093 
BPF_CALL_1(bpf_get_attach_cookie_tracing,void *,ctx)1094 BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx)
1095 {
1096 	struct bpf_trace_run_ctx *run_ctx;
1097 
1098 	run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
1099 	return run_ctx->bpf_cookie;
1100 }
1101 
1102 static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = {
1103 	.func		= bpf_get_attach_cookie_tracing,
1104 	.gpl_only	= false,
1105 	.ret_type	= RET_INTEGER,
1106 	.arg1_type	= ARG_PTR_TO_CTX,
1107 };
1108 
BPF_CALL_3(bpf_get_branch_snapshot,void *,buf,u32,size,u64,flags)1109 BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags)
1110 {
1111 #ifndef CONFIG_X86
1112 	return -ENOENT;
1113 #else
1114 	static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1115 	u32 entry_cnt = size / br_entry_size;
1116 
1117 	entry_cnt = static_call(perf_snapshot_branch_stack)(buf, entry_cnt);
1118 
1119 	if (unlikely(flags))
1120 		return -EINVAL;
1121 
1122 	if (!entry_cnt)
1123 		return -ENOENT;
1124 
1125 	return entry_cnt * br_entry_size;
1126 #endif
1127 }
1128 
1129 static const struct bpf_func_proto bpf_get_branch_snapshot_proto = {
1130 	.func		= bpf_get_branch_snapshot,
1131 	.gpl_only	= true,
1132 	.ret_type	= RET_INTEGER,
1133 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
1134 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
1135 };
1136 
BPF_CALL_3(get_func_arg,void *,ctx,u32,n,u64 *,value)1137 BPF_CALL_3(get_func_arg, void *, ctx, u32, n, u64 *, value)
1138 {
1139 	/* This helper call is inlined by verifier. */
1140 	u64 nr_args = ((u64 *)ctx)[-1];
1141 
1142 	if ((u64) n >= nr_args)
1143 		return -EINVAL;
1144 	*value = ((u64 *)ctx)[n];
1145 	return 0;
1146 }
1147 
1148 static const struct bpf_func_proto bpf_get_func_arg_proto = {
1149 	.func		= get_func_arg,
1150 	.ret_type	= RET_INTEGER,
1151 	.arg1_type	= ARG_PTR_TO_CTX,
1152 	.arg2_type	= ARG_ANYTHING,
1153 	.arg3_type	= ARG_PTR_TO_LONG,
1154 };
1155 
BPF_CALL_2(get_func_ret,void *,ctx,u64 *,value)1156 BPF_CALL_2(get_func_ret, void *, ctx, u64 *, value)
1157 {
1158 	/* This helper call is inlined by verifier. */
1159 	u64 nr_args = ((u64 *)ctx)[-1];
1160 
1161 	*value = ((u64 *)ctx)[nr_args];
1162 	return 0;
1163 }
1164 
1165 static const struct bpf_func_proto bpf_get_func_ret_proto = {
1166 	.func		= get_func_ret,
1167 	.ret_type	= RET_INTEGER,
1168 	.arg1_type	= ARG_PTR_TO_CTX,
1169 	.arg2_type	= ARG_PTR_TO_LONG,
1170 };
1171 
BPF_CALL_1(get_func_arg_cnt,void *,ctx)1172 BPF_CALL_1(get_func_arg_cnt, void *, ctx)
1173 {
1174 	/* This helper call is inlined by verifier. */
1175 	return ((u64 *)ctx)[-1];
1176 }
1177 
1178 static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = {
1179 	.func		= get_func_arg_cnt,
1180 	.ret_type	= RET_INTEGER,
1181 	.arg1_type	= ARG_PTR_TO_CTX,
1182 };
1183 
1184 static const struct bpf_func_proto *
bpf_tracing_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1185 bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1186 {
1187 	switch (func_id) {
1188 	case BPF_FUNC_map_lookup_elem:
1189 		return &bpf_map_lookup_elem_proto;
1190 	case BPF_FUNC_map_update_elem:
1191 		return &bpf_map_update_elem_proto;
1192 	case BPF_FUNC_map_delete_elem:
1193 		return &bpf_map_delete_elem_proto;
1194 	case BPF_FUNC_map_push_elem:
1195 		return &bpf_map_push_elem_proto;
1196 	case BPF_FUNC_map_pop_elem:
1197 		return &bpf_map_pop_elem_proto;
1198 	case BPF_FUNC_map_peek_elem:
1199 		return &bpf_map_peek_elem_proto;
1200 	case BPF_FUNC_map_lookup_percpu_elem:
1201 		return &bpf_map_lookup_percpu_elem_proto;
1202 	case BPF_FUNC_ktime_get_ns:
1203 		return &bpf_ktime_get_ns_proto;
1204 	case BPF_FUNC_ktime_get_boot_ns:
1205 		return &bpf_ktime_get_boot_ns_proto;
1206 	case BPF_FUNC_tail_call:
1207 		return &bpf_tail_call_proto;
1208 	case BPF_FUNC_get_current_pid_tgid:
1209 		return &bpf_get_current_pid_tgid_proto;
1210 	case BPF_FUNC_get_current_task:
1211 		return &bpf_get_current_task_proto;
1212 	case BPF_FUNC_get_current_task_btf:
1213 		return &bpf_get_current_task_btf_proto;
1214 	case BPF_FUNC_task_pt_regs:
1215 		return &bpf_task_pt_regs_proto;
1216 	case BPF_FUNC_get_current_uid_gid:
1217 		return &bpf_get_current_uid_gid_proto;
1218 	case BPF_FUNC_get_current_comm:
1219 		return &bpf_get_current_comm_proto;
1220 	case BPF_FUNC_trace_printk:
1221 		return bpf_get_trace_printk_proto();
1222 	case BPF_FUNC_get_smp_processor_id:
1223 		return &bpf_get_smp_processor_id_proto;
1224 	case BPF_FUNC_get_numa_node_id:
1225 		return &bpf_get_numa_node_id_proto;
1226 	case BPF_FUNC_perf_event_read:
1227 		return &bpf_perf_event_read_proto;
1228 	case BPF_FUNC_current_task_under_cgroup:
1229 		return &bpf_current_task_under_cgroup_proto;
1230 	case BPF_FUNC_get_prandom_u32:
1231 		return &bpf_get_prandom_u32_proto;
1232 	case BPF_FUNC_probe_write_user:
1233 		return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ?
1234 		       NULL : bpf_get_probe_write_proto();
1235 	case BPF_FUNC_probe_read_user:
1236 		return &bpf_probe_read_user_proto;
1237 	case BPF_FUNC_probe_read_kernel:
1238 		return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1239 		       NULL : &bpf_probe_read_kernel_proto;
1240 	case BPF_FUNC_probe_read_user_str:
1241 		return &bpf_probe_read_user_str_proto;
1242 	case BPF_FUNC_probe_read_kernel_str:
1243 		return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1244 		       NULL : &bpf_probe_read_kernel_str_proto;
1245 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
1246 	case BPF_FUNC_probe_read:
1247 		return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1248 		       NULL : &bpf_probe_read_compat_proto;
1249 	case BPF_FUNC_probe_read_str:
1250 		return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
1251 		       NULL : &bpf_probe_read_compat_str_proto;
1252 #endif
1253 #ifdef CONFIG_CGROUPS
1254 	case BPF_FUNC_get_current_cgroup_id:
1255 		return &bpf_get_current_cgroup_id_proto;
1256 	case BPF_FUNC_get_current_ancestor_cgroup_id:
1257 		return &bpf_get_current_ancestor_cgroup_id_proto;
1258 #endif
1259 	case BPF_FUNC_send_signal:
1260 		return &bpf_send_signal_proto;
1261 	case BPF_FUNC_send_signal_thread:
1262 		return &bpf_send_signal_thread_proto;
1263 	case BPF_FUNC_perf_event_read_value:
1264 		return &bpf_perf_event_read_value_proto;
1265 	case BPF_FUNC_get_ns_current_pid_tgid:
1266 		return &bpf_get_ns_current_pid_tgid_proto;
1267 	case BPF_FUNC_ringbuf_output:
1268 		return &bpf_ringbuf_output_proto;
1269 	case BPF_FUNC_ringbuf_reserve:
1270 		return &bpf_ringbuf_reserve_proto;
1271 	case BPF_FUNC_ringbuf_submit:
1272 		return &bpf_ringbuf_submit_proto;
1273 	case BPF_FUNC_ringbuf_discard:
1274 		return &bpf_ringbuf_discard_proto;
1275 	case BPF_FUNC_ringbuf_query:
1276 		return &bpf_ringbuf_query_proto;
1277 	case BPF_FUNC_jiffies64:
1278 		return &bpf_jiffies64_proto;
1279 	case BPF_FUNC_get_task_stack:
1280 		return &bpf_get_task_stack_proto;
1281 	case BPF_FUNC_copy_from_user:
1282 		return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL;
1283 	case BPF_FUNC_copy_from_user_task:
1284 		return prog->aux->sleepable ? &bpf_copy_from_user_task_proto : NULL;
1285 	case BPF_FUNC_snprintf_btf:
1286 		return &bpf_snprintf_btf_proto;
1287 	case BPF_FUNC_per_cpu_ptr:
1288 		return &bpf_per_cpu_ptr_proto;
1289 	case BPF_FUNC_this_cpu_ptr:
1290 		return &bpf_this_cpu_ptr_proto;
1291 	case BPF_FUNC_task_storage_get:
1292 		return &bpf_task_storage_get_proto;
1293 	case BPF_FUNC_task_storage_delete:
1294 		return &bpf_task_storage_delete_proto;
1295 	case BPF_FUNC_for_each_map_elem:
1296 		return &bpf_for_each_map_elem_proto;
1297 	case BPF_FUNC_snprintf:
1298 		return &bpf_snprintf_proto;
1299 	case BPF_FUNC_get_func_ip:
1300 		return &bpf_get_func_ip_proto_tracing;
1301 	case BPF_FUNC_get_branch_snapshot:
1302 		return &bpf_get_branch_snapshot_proto;
1303 	case BPF_FUNC_find_vma:
1304 		return &bpf_find_vma_proto;
1305 	case BPF_FUNC_trace_vprintk:
1306 		return bpf_get_trace_vprintk_proto();
1307 	default:
1308 		return bpf_base_func_proto(func_id);
1309 	}
1310 }
1311 
1312 static const struct bpf_func_proto *
kprobe_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1313 kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1314 {
1315 	switch (func_id) {
1316 	case BPF_FUNC_perf_event_output:
1317 		return &bpf_perf_event_output_proto;
1318 	case BPF_FUNC_get_stackid:
1319 		return &bpf_get_stackid_proto;
1320 	case BPF_FUNC_get_stack:
1321 		return &bpf_get_stack_proto;
1322 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
1323 	case BPF_FUNC_override_return:
1324 		return &bpf_override_return_proto;
1325 #endif
1326 	case BPF_FUNC_get_func_ip:
1327 		return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
1328 			&bpf_get_func_ip_proto_kprobe_multi :
1329 			&bpf_get_func_ip_proto_kprobe;
1330 	case BPF_FUNC_get_attach_cookie:
1331 		return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
1332 			&bpf_get_attach_cookie_proto_kmulti :
1333 			&bpf_get_attach_cookie_proto_trace;
1334 	default:
1335 		return bpf_tracing_func_proto(func_id, prog);
1336 	}
1337 }
1338 
1339 /* bpf+kprobe programs can access fields of 'struct pt_regs' */
kprobe_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1340 static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1341 					const struct bpf_prog *prog,
1342 					struct bpf_insn_access_aux *info)
1343 {
1344 	if (off < 0 || off >= sizeof(struct pt_regs))
1345 		return false;
1346 	if (type != BPF_READ)
1347 		return false;
1348 	if (off % size != 0)
1349 		return false;
1350 	/*
1351 	 * Assertion for 32 bit to make sure last 8 byte access
1352 	 * (BPF_DW) to the last 4 byte member is disallowed.
1353 	 */
1354 	if (off + size > sizeof(struct pt_regs))
1355 		return false;
1356 
1357 	return true;
1358 }
1359 
1360 const struct bpf_verifier_ops kprobe_verifier_ops = {
1361 	.get_func_proto  = kprobe_prog_func_proto,
1362 	.is_valid_access = kprobe_prog_is_valid_access,
1363 };
1364 
1365 const struct bpf_prog_ops kprobe_prog_ops = {
1366 };
1367 
BPF_CALL_5(bpf_perf_event_output_tp,void *,tp_buff,struct bpf_map *,map,u64,flags,void *,data,u64,size)1368 BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
1369 	   u64, flags, void *, data, u64, size)
1370 {
1371 	struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1372 
1373 	/*
1374 	 * r1 points to perf tracepoint buffer where first 8 bytes are hidden
1375 	 * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
1376 	 * from there and call the same bpf_perf_event_output() helper inline.
1377 	 */
1378 	return ____bpf_perf_event_output(regs, map, flags, data, size);
1379 }
1380 
1381 static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
1382 	.func		= bpf_perf_event_output_tp,
1383 	.gpl_only	= true,
1384 	.ret_type	= RET_INTEGER,
1385 	.arg1_type	= ARG_PTR_TO_CTX,
1386 	.arg2_type	= ARG_CONST_MAP_PTR,
1387 	.arg3_type	= ARG_ANYTHING,
1388 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1389 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
1390 };
1391 
BPF_CALL_3(bpf_get_stackid_tp,void *,tp_buff,struct bpf_map *,map,u64,flags)1392 BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
1393 	   u64, flags)
1394 {
1395 	struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1396 
1397 	/*
1398 	 * Same comment as in bpf_perf_event_output_tp(), only that this time
1399 	 * the other helper's function body cannot be inlined due to being
1400 	 * external, thus we need to call raw helper function.
1401 	 */
1402 	return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1403 			       flags, 0, 0);
1404 }
1405 
1406 static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
1407 	.func		= bpf_get_stackid_tp,
1408 	.gpl_only	= true,
1409 	.ret_type	= RET_INTEGER,
1410 	.arg1_type	= ARG_PTR_TO_CTX,
1411 	.arg2_type	= ARG_CONST_MAP_PTR,
1412 	.arg3_type	= ARG_ANYTHING,
1413 };
1414 
BPF_CALL_4(bpf_get_stack_tp,void *,tp_buff,void *,buf,u32,size,u64,flags)1415 BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size,
1416 	   u64, flags)
1417 {
1418 	struct pt_regs *regs = *(struct pt_regs **)tp_buff;
1419 
1420 	return bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1421 			     (unsigned long) size, flags, 0);
1422 }
1423 
1424 static const struct bpf_func_proto bpf_get_stack_proto_tp = {
1425 	.func		= bpf_get_stack_tp,
1426 	.gpl_only	= true,
1427 	.ret_type	= RET_INTEGER,
1428 	.arg1_type	= ARG_PTR_TO_CTX,
1429 	.arg2_type	= ARG_PTR_TO_UNINIT_MEM,
1430 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
1431 	.arg4_type	= ARG_ANYTHING,
1432 };
1433 
1434 static const struct bpf_func_proto *
tp_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1435 tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1436 {
1437 	switch (func_id) {
1438 	case BPF_FUNC_perf_event_output:
1439 		return &bpf_perf_event_output_proto_tp;
1440 	case BPF_FUNC_get_stackid:
1441 		return &bpf_get_stackid_proto_tp;
1442 	case BPF_FUNC_get_stack:
1443 		return &bpf_get_stack_proto_tp;
1444 	case BPF_FUNC_get_attach_cookie:
1445 		return &bpf_get_attach_cookie_proto_trace;
1446 	default:
1447 		return bpf_tracing_func_proto(func_id, prog);
1448 	}
1449 }
1450 
tp_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1451 static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1452 				    const struct bpf_prog *prog,
1453 				    struct bpf_insn_access_aux *info)
1454 {
1455 	if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
1456 		return false;
1457 	if (type != BPF_READ)
1458 		return false;
1459 	if (off % size != 0)
1460 		return false;
1461 
1462 	BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
1463 	return true;
1464 }
1465 
1466 const struct bpf_verifier_ops tracepoint_verifier_ops = {
1467 	.get_func_proto  = tp_prog_func_proto,
1468 	.is_valid_access = tp_prog_is_valid_access,
1469 };
1470 
1471 const struct bpf_prog_ops tracepoint_prog_ops = {
1472 };
1473 
BPF_CALL_3(bpf_perf_prog_read_value,struct bpf_perf_event_data_kern *,ctx,struct bpf_perf_event_value *,buf,u32,size)1474 BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
1475 	   struct bpf_perf_event_value *, buf, u32, size)
1476 {
1477 	int err = -EINVAL;
1478 
1479 	if (unlikely(size != sizeof(struct bpf_perf_event_value)))
1480 		goto clear;
1481 	err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
1482 				    &buf->running);
1483 	if (unlikely(err))
1484 		goto clear;
1485 	return 0;
1486 clear:
1487 	memset(buf, 0, size);
1488 	return err;
1489 }
1490 
1491 static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
1492          .func           = bpf_perf_prog_read_value,
1493          .gpl_only       = true,
1494          .ret_type       = RET_INTEGER,
1495          .arg1_type      = ARG_PTR_TO_CTX,
1496          .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
1497          .arg3_type      = ARG_CONST_SIZE,
1498 };
1499 
BPF_CALL_4(bpf_read_branch_records,struct bpf_perf_event_data_kern *,ctx,void *,buf,u32,size,u64,flags)1500 BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
1501 	   void *, buf, u32, size, u64, flags)
1502 {
1503 	static const u32 br_entry_size = sizeof(struct perf_branch_entry);
1504 	struct perf_branch_stack *br_stack = ctx->data->br_stack;
1505 	u32 to_copy;
1506 
1507 	if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
1508 		return -EINVAL;
1509 
1510 	if (unlikely(!br_stack))
1511 		return -ENOENT;
1512 
1513 	if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE)
1514 		return br_stack->nr * br_entry_size;
1515 
1516 	if (!buf || (size % br_entry_size != 0))
1517 		return -EINVAL;
1518 
1519 	to_copy = min_t(u32, br_stack->nr * br_entry_size, size);
1520 	memcpy(buf, br_stack->entries, to_copy);
1521 
1522 	return to_copy;
1523 }
1524 
1525 static const struct bpf_func_proto bpf_read_branch_records_proto = {
1526 	.func           = bpf_read_branch_records,
1527 	.gpl_only       = true,
1528 	.ret_type       = RET_INTEGER,
1529 	.arg1_type      = ARG_PTR_TO_CTX,
1530 	.arg2_type      = ARG_PTR_TO_MEM_OR_NULL,
1531 	.arg3_type      = ARG_CONST_SIZE_OR_ZERO,
1532 	.arg4_type      = ARG_ANYTHING,
1533 };
1534 
1535 static const struct bpf_func_proto *
pe_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1536 pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1537 {
1538 	switch (func_id) {
1539 	case BPF_FUNC_perf_event_output:
1540 		return &bpf_perf_event_output_proto_tp;
1541 	case BPF_FUNC_get_stackid:
1542 		return &bpf_get_stackid_proto_pe;
1543 	case BPF_FUNC_get_stack:
1544 		return &bpf_get_stack_proto_pe;
1545 	case BPF_FUNC_perf_prog_read_value:
1546 		return &bpf_perf_prog_read_value_proto;
1547 	case BPF_FUNC_read_branch_records:
1548 		return &bpf_read_branch_records_proto;
1549 	case BPF_FUNC_get_attach_cookie:
1550 		return &bpf_get_attach_cookie_proto_pe;
1551 	default:
1552 		return bpf_tracing_func_proto(func_id, prog);
1553 	}
1554 }
1555 
1556 /*
1557  * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
1558  * to avoid potential recursive reuse issue when/if tracepoints are added
1559  * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack.
1560  *
1561  * Since raw tracepoints run despite bpf_prog_active, support concurrent usage
1562  * in normal, irq, and nmi context.
1563  */
1564 struct bpf_raw_tp_regs {
1565 	struct pt_regs regs[3];
1566 };
1567 static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs);
1568 static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level);
get_bpf_raw_tp_regs(void)1569 static struct pt_regs *get_bpf_raw_tp_regs(void)
1570 {
1571 	struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs);
1572 	int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level);
1573 
1574 	if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) {
1575 		this_cpu_dec(bpf_raw_tp_nest_level);
1576 		return ERR_PTR(-EBUSY);
1577 	}
1578 
1579 	return &tp_regs->regs[nest_level - 1];
1580 }
1581 
put_bpf_raw_tp_regs(void)1582 static void put_bpf_raw_tp_regs(void)
1583 {
1584 	this_cpu_dec(bpf_raw_tp_nest_level);
1585 }
1586 
BPF_CALL_5(bpf_perf_event_output_raw_tp,struct bpf_raw_tracepoint_args *,args,struct bpf_map *,map,u64,flags,void *,data,u64,size)1587 BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
1588 	   struct bpf_map *, map, u64, flags, void *, data, u64, size)
1589 {
1590 	struct pt_regs *regs = get_bpf_raw_tp_regs();
1591 	int ret;
1592 
1593 	if (IS_ERR(regs))
1594 		return PTR_ERR(regs);
1595 
1596 	perf_fetch_caller_regs(regs);
1597 	ret = ____bpf_perf_event_output(regs, map, flags, data, size);
1598 
1599 	put_bpf_raw_tp_regs();
1600 	return ret;
1601 }
1602 
1603 static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
1604 	.func		= bpf_perf_event_output_raw_tp,
1605 	.gpl_only	= true,
1606 	.ret_type	= RET_INTEGER,
1607 	.arg1_type	= ARG_PTR_TO_CTX,
1608 	.arg2_type	= ARG_CONST_MAP_PTR,
1609 	.arg3_type	= ARG_ANYTHING,
1610 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1611 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
1612 };
1613 
1614 extern const struct bpf_func_proto bpf_skb_output_proto;
1615 extern const struct bpf_func_proto bpf_xdp_output_proto;
1616 extern const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto;
1617 
BPF_CALL_3(bpf_get_stackid_raw_tp,struct bpf_raw_tracepoint_args *,args,struct bpf_map *,map,u64,flags)1618 BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
1619 	   struct bpf_map *, map, u64, flags)
1620 {
1621 	struct pt_regs *regs = get_bpf_raw_tp_regs();
1622 	int ret;
1623 
1624 	if (IS_ERR(regs))
1625 		return PTR_ERR(regs);
1626 
1627 	perf_fetch_caller_regs(regs);
1628 	/* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
1629 	ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map,
1630 			      flags, 0, 0);
1631 	put_bpf_raw_tp_regs();
1632 	return ret;
1633 }
1634 
1635 static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
1636 	.func		= bpf_get_stackid_raw_tp,
1637 	.gpl_only	= true,
1638 	.ret_type	= RET_INTEGER,
1639 	.arg1_type	= ARG_PTR_TO_CTX,
1640 	.arg2_type	= ARG_CONST_MAP_PTR,
1641 	.arg3_type	= ARG_ANYTHING,
1642 };
1643 
BPF_CALL_4(bpf_get_stack_raw_tp,struct bpf_raw_tracepoint_args *,args,void *,buf,u32,size,u64,flags)1644 BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args,
1645 	   void *, buf, u32, size, u64, flags)
1646 {
1647 	struct pt_regs *regs = get_bpf_raw_tp_regs();
1648 	int ret;
1649 
1650 	if (IS_ERR(regs))
1651 		return PTR_ERR(regs);
1652 
1653 	perf_fetch_caller_regs(regs);
1654 	ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf,
1655 			    (unsigned long) size, flags, 0);
1656 	put_bpf_raw_tp_regs();
1657 	return ret;
1658 }
1659 
1660 static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = {
1661 	.func		= bpf_get_stack_raw_tp,
1662 	.gpl_only	= true,
1663 	.ret_type	= RET_INTEGER,
1664 	.arg1_type	= ARG_PTR_TO_CTX,
1665 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1666 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
1667 	.arg4_type	= ARG_ANYTHING,
1668 };
1669 
1670 static const struct bpf_func_proto *
raw_tp_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1671 raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1672 {
1673 	switch (func_id) {
1674 	case BPF_FUNC_perf_event_output:
1675 		return &bpf_perf_event_output_proto_raw_tp;
1676 	case BPF_FUNC_get_stackid:
1677 		return &bpf_get_stackid_proto_raw_tp;
1678 	case BPF_FUNC_get_stack:
1679 		return &bpf_get_stack_proto_raw_tp;
1680 	default:
1681 		return bpf_tracing_func_proto(func_id, prog);
1682 	}
1683 }
1684 
1685 const struct bpf_func_proto *
tracing_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)1686 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
1687 {
1688 	const struct bpf_func_proto *fn;
1689 
1690 	switch (func_id) {
1691 #ifdef CONFIG_NET
1692 	case BPF_FUNC_skb_output:
1693 		return &bpf_skb_output_proto;
1694 	case BPF_FUNC_xdp_output:
1695 		return &bpf_xdp_output_proto;
1696 	case BPF_FUNC_skc_to_tcp6_sock:
1697 		return &bpf_skc_to_tcp6_sock_proto;
1698 	case BPF_FUNC_skc_to_tcp_sock:
1699 		return &bpf_skc_to_tcp_sock_proto;
1700 	case BPF_FUNC_skc_to_tcp_timewait_sock:
1701 		return &bpf_skc_to_tcp_timewait_sock_proto;
1702 	case BPF_FUNC_skc_to_tcp_request_sock:
1703 		return &bpf_skc_to_tcp_request_sock_proto;
1704 	case BPF_FUNC_skc_to_udp6_sock:
1705 		return &bpf_skc_to_udp6_sock_proto;
1706 	case BPF_FUNC_skc_to_unix_sock:
1707 		return &bpf_skc_to_unix_sock_proto;
1708 	case BPF_FUNC_skc_to_mptcp_sock:
1709 		return &bpf_skc_to_mptcp_sock_proto;
1710 	case BPF_FUNC_sk_storage_get:
1711 		return &bpf_sk_storage_get_tracing_proto;
1712 	case BPF_FUNC_sk_storage_delete:
1713 		return &bpf_sk_storage_delete_tracing_proto;
1714 	case BPF_FUNC_sock_from_file:
1715 		return &bpf_sock_from_file_proto;
1716 	case BPF_FUNC_get_socket_cookie:
1717 		return &bpf_get_socket_ptr_cookie_proto;
1718 	case BPF_FUNC_xdp_get_buff_len:
1719 		return &bpf_xdp_get_buff_len_trace_proto;
1720 #endif
1721 	case BPF_FUNC_seq_printf:
1722 		return prog->expected_attach_type == BPF_TRACE_ITER ?
1723 		       &bpf_seq_printf_proto :
1724 		       NULL;
1725 	case BPF_FUNC_seq_write:
1726 		return prog->expected_attach_type == BPF_TRACE_ITER ?
1727 		       &bpf_seq_write_proto :
1728 		       NULL;
1729 	case BPF_FUNC_seq_printf_btf:
1730 		return prog->expected_attach_type == BPF_TRACE_ITER ?
1731 		       &bpf_seq_printf_btf_proto :
1732 		       NULL;
1733 	case BPF_FUNC_d_path:
1734 		return &bpf_d_path_proto;
1735 	case BPF_FUNC_get_func_arg:
1736 		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_proto : NULL;
1737 	case BPF_FUNC_get_func_ret:
1738 		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL;
1739 	case BPF_FUNC_get_func_arg_cnt:
1740 		return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL;
1741 	case BPF_FUNC_get_attach_cookie:
1742 		return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL;
1743 	default:
1744 		fn = raw_tp_prog_func_proto(func_id, prog);
1745 		if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)
1746 			fn = bpf_iter_get_func_proto(func_id, prog);
1747 		return fn;
1748 	}
1749 }
1750 
raw_tp_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1751 static bool raw_tp_prog_is_valid_access(int off, int size,
1752 					enum bpf_access_type type,
1753 					const struct bpf_prog *prog,
1754 					struct bpf_insn_access_aux *info)
1755 {
1756 	return bpf_tracing_ctx_access(off, size, type);
1757 }
1758 
tracing_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1759 static bool tracing_prog_is_valid_access(int off, int size,
1760 					 enum bpf_access_type type,
1761 					 const struct bpf_prog *prog,
1762 					 struct bpf_insn_access_aux *info)
1763 {
1764 	return bpf_tracing_btf_ctx_access(off, size, type, prog, info);
1765 }
1766 
bpf_prog_test_run_tracing(struct bpf_prog * prog,const union bpf_attr * kattr,union bpf_attr __user * uattr)1767 int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog,
1768 				     const union bpf_attr *kattr,
1769 				     union bpf_attr __user *uattr)
1770 {
1771 	return -ENOTSUPP;
1772 }
1773 
1774 const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
1775 	.get_func_proto  = raw_tp_prog_func_proto,
1776 	.is_valid_access = raw_tp_prog_is_valid_access,
1777 };
1778 
1779 const struct bpf_prog_ops raw_tracepoint_prog_ops = {
1780 #ifdef CONFIG_NET
1781 	.test_run = bpf_prog_test_run_raw_tp,
1782 #endif
1783 };
1784 
1785 const struct bpf_verifier_ops tracing_verifier_ops = {
1786 	.get_func_proto  = tracing_prog_func_proto,
1787 	.is_valid_access = tracing_prog_is_valid_access,
1788 };
1789 
1790 const struct bpf_prog_ops tracing_prog_ops = {
1791 	.test_run = bpf_prog_test_run_tracing,
1792 };
1793 
raw_tp_writable_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1794 static bool raw_tp_writable_prog_is_valid_access(int off, int size,
1795 						 enum bpf_access_type type,
1796 						 const struct bpf_prog *prog,
1797 						 struct bpf_insn_access_aux *info)
1798 {
1799 	if (off == 0) {
1800 		if (size != sizeof(u64) || type != BPF_READ)
1801 			return false;
1802 		info->reg_type = PTR_TO_TP_BUFFER;
1803 	}
1804 	return raw_tp_prog_is_valid_access(off, size, type, prog, info);
1805 }
1806 
1807 const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = {
1808 	.get_func_proto  = raw_tp_prog_func_proto,
1809 	.is_valid_access = raw_tp_writable_prog_is_valid_access,
1810 };
1811 
1812 const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = {
1813 };
1814 
pe_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)1815 static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
1816 				    const struct bpf_prog *prog,
1817 				    struct bpf_insn_access_aux *info)
1818 {
1819 	const int size_u64 = sizeof(u64);
1820 
1821 	if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
1822 		return false;
1823 	if (type != BPF_READ)
1824 		return false;
1825 	if (off % size != 0) {
1826 		if (sizeof(unsigned long) != 4)
1827 			return false;
1828 		if (size != 8)
1829 			return false;
1830 		if (off % size != 4)
1831 			return false;
1832 	}
1833 
1834 	switch (off) {
1835 	case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
1836 		bpf_ctx_record_field_size(info, size_u64);
1837 		if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
1838 			return false;
1839 		break;
1840 	case bpf_ctx_range(struct bpf_perf_event_data, addr):
1841 		bpf_ctx_record_field_size(info, size_u64);
1842 		if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
1843 			return false;
1844 		break;
1845 	default:
1846 		if (size != sizeof(long))
1847 			return false;
1848 	}
1849 
1850 	return true;
1851 }
1852 
pe_prog_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)1853 static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
1854 				      const struct bpf_insn *si,
1855 				      struct bpf_insn *insn_buf,
1856 				      struct bpf_prog *prog, u32 *target_size)
1857 {
1858 	struct bpf_insn *insn = insn_buf;
1859 
1860 	switch (si->off) {
1861 	case offsetof(struct bpf_perf_event_data, sample_period):
1862 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1863 						       data), si->dst_reg, si->src_reg,
1864 				      offsetof(struct bpf_perf_event_data_kern, data));
1865 		*insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
1866 				      bpf_target_off(struct perf_sample_data, period, 8,
1867 						     target_size));
1868 		break;
1869 	case offsetof(struct bpf_perf_event_data, addr):
1870 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1871 						       data), si->dst_reg, si->src_reg,
1872 				      offsetof(struct bpf_perf_event_data_kern, data));
1873 		*insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
1874 				      bpf_target_off(struct perf_sample_data, addr, 8,
1875 						     target_size));
1876 		break;
1877 	default:
1878 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
1879 						       regs), si->dst_reg, si->src_reg,
1880 				      offsetof(struct bpf_perf_event_data_kern, regs));
1881 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
1882 				      si->off);
1883 		break;
1884 	}
1885 
1886 	return insn - insn_buf;
1887 }
1888 
1889 const struct bpf_verifier_ops perf_event_verifier_ops = {
1890 	.get_func_proto		= pe_prog_func_proto,
1891 	.is_valid_access	= pe_prog_is_valid_access,
1892 	.convert_ctx_access	= pe_prog_convert_ctx_access,
1893 };
1894 
1895 const struct bpf_prog_ops perf_event_prog_ops = {
1896 };
1897 
1898 static DEFINE_MUTEX(bpf_event_mutex);
1899 
1900 #define BPF_TRACE_MAX_PROGS 64
1901 
perf_event_attach_bpf_prog(struct perf_event * event,struct bpf_prog * prog,u64 bpf_cookie)1902 int perf_event_attach_bpf_prog(struct perf_event *event,
1903 			       struct bpf_prog *prog,
1904 			       u64 bpf_cookie)
1905 {
1906 	struct bpf_prog_array *old_array;
1907 	struct bpf_prog_array *new_array;
1908 	int ret = -EEXIST;
1909 
1910 	/*
1911 	 * Kprobe override only works if they are on the function entry,
1912 	 * and only if they are on the opt-in list.
1913 	 */
1914 	if (prog->kprobe_override &&
1915 	    (!trace_kprobe_on_func_entry(event->tp_event) ||
1916 	     !trace_kprobe_error_injectable(event->tp_event)))
1917 		return -EINVAL;
1918 
1919 	mutex_lock(&bpf_event_mutex);
1920 
1921 	if (event->prog)
1922 		goto unlock;
1923 
1924 	old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
1925 	if (old_array &&
1926 	    bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
1927 		ret = -E2BIG;
1928 		goto unlock;
1929 	}
1930 
1931 	ret = bpf_prog_array_copy(old_array, NULL, prog, bpf_cookie, &new_array);
1932 	if (ret < 0)
1933 		goto unlock;
1934 
1935 	/* set the new array to event->tp_event and set event->prog */
1936 	event->prog = prog;
1937 	event->bpf_cookie = bpf_cookie;
1938 	rcu_assign_pointer(event->tp_event->prog_array, new_array);
1939 	bpf_prog_array_free(old_array);
1940 
1941 unlock:
1942 	mutex_unlock(&bpf_event_mutex);
1943 	return ret;
1944 }
1945 
perf_event_detach_bpf_prog(struct perf_event * event)1946 void perf_event_detach_bpf_prog(struct perf_event *event)
1947 {
1948 	struct bpf_prog_array *old_array;
1949 	struct bpf_prog_array *new_array;
1950 	int ret;
1951 
1952 	mutex_lock(&bpf_event_mutex);
1953 
1954 	if (!event->prog)
1955 		goto unlock;
1956 
1957 	old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
1958 	ret = bpf_prog_array_copy(old_array, event->prog, NULL, 0, &new_array);
1959 	if (ret == -ENOENT)
1960 		goto unlock;
1961 	if (ret < 0) {
1962 		bpf_prog_array_delete_safe(old_array, event->prog);
1963 	} else {
1964 		rcu_assign_pointer(event->tp_event->prog_array, new_array);
1965 		bpf_prog_array_free(old_array);
1966 	}
1967 
1968 	bpf_prog_put(event->prog);
1969 	event->prog = NULL;
1970 
1971 unlock:
1972 	mutex_unlock(&bpf_event_mutex);
1973 }
1974 
perf_event_query_prog_array(struct perf_event * event,void __user * info)1975 int perf_event_query_prog_array(struct perf_event *event, void __user *info)
1976 {
1977 	struct perf_event_query_bpf __user *uquery = info;
1978 	struct perf_event_query_bpf query = {};
1979 	struct bpf_prog_array *progs;
1980 	u32 *ids, prog_cnt, ids_len;
1981 	int ret;
1982 
1983 	if (!perfmon_capable())
1984 		return -EPERM;
1985 	if (event->attr.type != PERF_TYPE_TRACEPOINT)
1986 		return -EINVAL;
1987 	if (copy_from_user(&query, uquery, sizeof(query)))
1988 		return -EFAULT;
1989 
1990 	ids_len = query.ids_len;
1991 	if (ids_len > BPF_TRACE_MAX_PROGS)
1992 		return -E2BIG;
1993 	ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN);
1994 	if (!ids)
1995 		return -ENOMEM;
1996 	/*
1997 	 * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which
1998 	 * is required when user only wants to check for uquery->prog_cnt.
1999 	 * There is no need to check for it since the case is handled
2000 	 * gracefully in bpf_prog_array_copy_info.
2001 	 */
2002 
2003 	mutex_lock(&bpf_event_mutex);
2004 	progs = bpf_event_rcu_dereference(event->tp_event->prog_array);
2005 	ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt);
2006 	mutex_unlock(&bpf_event_mutex);
2007 
2008 	if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) ||
2009 	    copy_to_user(uquery->ids, ids, ids_len * sizeof(u32)))
2010 		ret = -EFAULT;
2011 
2012 	kfree(ids);
2013 	return ret;
2014 }
2015 
2016 extern struct bpf_raw_event_map __start__bpf_raw_tp[];
2017 extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
2018 
bpf_get_raw_tracepoint(const char * name)2019 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
2020 {
2021 	struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
2022 
2023 	for (; btp < __stop__bpf_raw_tp; btp++) {
2024 		if (!strcmp(btp->tp->name, name))
2025 			return btp;
2026 	}
2027 
2028 	return bpf_get_raw_tracepoint_module(name);
2029 }
2030 
bpf_put_raw_tracepoint(struct bpf_raw_event_map * btp)2031 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
2032 {
2033 	struct module *mod;
2034 
2035 	preempt_disable();
2036 	mod = __module_address((unsigned long)btp);
2037 	module_put(mod);
2038 	preempt_enable();
2039 }
2040 
2041 static __always_inline
__bpf_trace_run(struct bpf_prog * prog,u64 * args)2042 void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
2043 {
2044 	cant_sleep();
2045 	rcu_read_lock();
2046 	(void) bpf_prog_run(prog, args);
2047 	rcu_read_unlock();
2048 }
2049 
2050 #define UNPACK(...)			__VA_ARGS__
2051 #define REPEAT_1(FN, DL, X, ...)	FN(X)
2052 #define REPEAT_2(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
2053 #define REPEAT_3(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
2054 #define REPEAT_4(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
2055 #define REPEAT_5(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
2056 #define REPEAT_6(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
2057 #define REPEAT_7(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
2058 #define REPEAT_8(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
2059 #define REPEAT_9(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
2060 #define REPEAT_10(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
2061 #define REPEAT_11(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
2062 #define REPEAT_12(FN, DL, X, ...)	FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
2063 #define REPEAT(X, FN, DL, ...)		REPEAT_##X(FN, DL, __VA_ARGS__)
2064 
2065 #define SARG(X)		u64 arg##X
2066 #define COPY(X)		args[X] = arg##X
2067 
2068 #define __DL_COM	(,)
2069 #define __DL_SEM	(;)
2070 
2071 #define __SEQ_0_11	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
2072 
2073 #define BPF_TRACE_DEFN_x(x)						\
2074 	void bpf_trace_run##x(struct bpf_prog *prog,			\
2075 			      REPEAT(x, SARG, __DL_COM, __SEQ_0_11))	\
2076 	{								\
2077 		u64 args[x];						\
2078 		REPEAT(x, COPY, __DL_SEM, __SEQ_0_11);			\
2079 		__bpf_trace_run(prog, args);				\
2080 	}								\
2081 	EXPORT_SYMBOL_GPL(bpf_trace_run##x)
2082 BPF_TRACE_DEFN_x(1);
2083 BPF_TRACE_DEFN_x(2);
2084 BPF_TRACE_DEFN_x(3);
2085 BPF_TRACE_DEFN_x(4);
2086 BPF_TRACE_DEFN_x(5);
2087 BPF_TRACE_DEFN_x(6);
2088 BPF_TRACE_DEFN_x(7);
2089 BPF_TRACE_DEFN_x(8);
2090 BPF_TRACE_DEFN_x(9);
2091 BPF_TRACE_DEFN_x(10);
2092 BPF_TRACE_DEFN_x(11);
2093 BPF_TRACE_DEFN_x(12);
2094 
__bpf_probe_register(struct bpf_raw_event_map * btp,struct bpf_prog * prog)2095 static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2096 {
2097 	struct tracepoint *tp = btp->tp;
2098 
2099 	/*
2100 	 * check that program doesn't access arguments beyond what's
2101 	 * available in this tracepoint
2102 	 */
2103 	if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
2104 		return -EINVAL;
2105 
2106 	if (prog->aux->max_tp_access > btp->writable_size)
2107 		return -EINVAL;
2108 
2109 	return tracepoint_probe_register_may_exist(tp, (void *)btp->bpf_func,
2110 						   prog);
2111 }
2112 
bpf_probe_register(struct bpf_raw_event_map * btp,struct bpf_prog * prog)2113 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2114 {
2115 	return __bpf_probe_register(btp, prog);
2116 }
2117 
bpf_probe_unregister(struct bpf_raw_event_map * btp,struct bpf_prog * prog)2118 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
2119 {
2120 	return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
2121 }
2122 
bpf_get_perf_event_info(const struct perf_event * event,u32 * prog_id,u32 * fd_type,const char ** buf,u64 * probe_offset,u64 * probe_addr)2123 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
2124 			    u32 *fd_type, const char **buf,
2125 			    u64 *probe_offset, u64 *probe_addr)
2126 {
2127 	bool is_tracepoint, is_syscall_tp;
2128 	struct bpf_prog *prog;
2129 	int flags, err = 0;
2130 
2131 	prog = event->prog;
2132 	if (!prog)
2133 		return -ENOENT;
2134 
2135 	/* not supporting BPF_PROG_TYPE_PERF_EVENT yet */
2136 	if (prog->type == BPF_PROG_TYPE_PERF_EVENT)
2137 		return -EOPNOTSUPP;
2138 
2139 	*prog_id = prog->aux->id;
2140 	flags = event->tp_event->flags;
2141 	is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT;
2142 	is_syscall_tp = is_syscall_trace_event(event->tp_event);
2143 
2144 	if (is_tracepoint || is_syscall_tp) {
2145 		*buf = is_tracepoint ? event->tp_event->tp->name
2146 				     : event->tp_event->name;
2147 		*fd_type = BPF_FD_TYPE_TRACEPOINT;
2148 		*probe_offset = 0x0;
2149 		*probe_addr = 0x0;
2150 	} else {
2151 		/* kprobe/uprobe */
2152 		err = -EOPNOTSUPP;
2153 #ifdef CONFIG_KPROBE_EVENTS
2154 		if (flags & TRACE_EVENT_FL_KPROBE)
2155 			err = bpf_get_kprobe_info(event, fd_type, buf,
2156 						  probe_offset, probe_addr,
2157 						  event->attr.type == PERF_TYPE_TRACEPOINT);
2158 #endif
2159 #ifdef CONFIG_UPROBE_EVENTS
2160 		if (flags & TRACE_EVENT_FL_UPROBE)
2161 			err = bpf_get_uprobe_info(event, fd_type, buf,
2162 						  probe_offset,
2163 						  event->attr.type == PERF_TYPE_TRACEPOINT);
2164 #endif
2165 	}
2166 
2167 	return err;
2168 }
2169 
send_signal_irq_work_init(void)2170 static int __init send_signal_irq_work_init(void)
2171 {
2172 	int cpu;
2173 	struct send_signal_irq_work *work;
2174 
2175 	for_each_possible_cpu(cpu) {
2176 		work = per_cpu_ptr(&send_signal_work, cpu);
2177 		init_irq_work(&work->irq_work, do_bpf_send_signal);
2178 	}
2179 	return 0;
2180 }
2181 
2182 subsys_initcall(send_signal_irq_work_init);
2183 
2184 #ifdef CONFIG_MODULES
bpf_event_notify(struct notifier_block * nb,unsigned long op,void * module)2185 static int bpf_event_notify(struct notifier_block *nb, unsigned long op,
2186 			    void *module)
2187 {
2188 	struct bpf_trace_module *btm, *tmp;
2189 	struct module *mod = module;
2190 	int ret = 0;
2191 
2192 	if (mod->num_bpf_raw_events == 0 ||
2193 	    (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING))
2194 		goto out;
2195 
2196 	mutex_lock(&bpf_module_mutex);
2197 
2198 	switch (op) {
2199 	case MODULE_STATE_COMING:
2200 		btm = kzalloc(sizeof(*btm), GFP_KERNEL);
2201 		if (btm) {
2202 			btm->module = module;
2203 			list_add(&btm->list, &bpf_trace_modules);
2204 		} else {
2205 			ret = -ENOMEM;
2206 		}
2207 		break;
2208 	case MODULE_STATE_GOING:
2209 		list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) {
2210 			if (btm->module == module) {
2211 				list_del(&btm->list);
2212 				kfree(btm);
2213 				break;
2214 			}
2215 		}
2216 		break;
2217 	}
2218 
2219 	mutex_unlock(&bpf_module_mutex);
2220 
2221 out:
2222 	return notifier_from_errno(ret);
2223 }
2224 
2225 static struct notifier_block bpf_module_nb = {
2226 	.notifier_call = bpf_event_notify,
2227 };
2228 
bpf_event_init(void)2229 static int __init bpf_event_init(void)
2230 {
2231 	register_module_notifier(&bpf_module_nb);
2232 	return 0;
2233 }
2234 
2235 fs_initcall(bpf_event_init);
2236 #endif /* CONFIG_MODULES */
2237 
2238 #ifdef CONFIG_FPROBE
2239 struct bpf_kprobe_multi_link {
2240 	struct bpf_link link;
2241 	struct fprobe fp;
2242 	unsigned long *addrs;
2243 	u64 *cookies;
2244 	u32 cnt;
2245 };
2246 
2247 struct bpf_kprobe_multi_run_ctx {
2248 	struct bpf_run_ctx run_ctx;
2249 	struct bpf_kprobe_multi_link *link;
2250 	unsigned long entry_ip;
2251 };
2252 
2253 struct user_syms {
2254 	const char **syms;
2255 	char *buf;
2256 };
2257 
copy_user_syms(struct user_syms * us,unsigned long __user * usyms,u32 cnt)2258 static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt)
2259 {
2260 	unsigned long __user usymbol;
2261 	const char **syms = NULL;
2262 	char *buf = NULL, *p;
2263 	int err = -ENOMEM;
2264 	unsigned int i;
2265 
2266 	syms = kvmalloc_array(cnt, sizeof(*syms), GFP_KERNEL);
2267 	if (!syms)
2268 		goto error;
2269 
2270 	buf = kvmalloc_array(cnt, KSYM_NAME_LEN, GFP_KERNEL);
2271 	if (!buf)
2272 		goto error;
2273 
2274 	for (p = buf, i = 0; i < cnt; i++) {
2275 		if (__get_user(usymbol, usyms + i)) {
2276 			err = -EFAULT;
2277 			goto error;
2278 		}
2279 		err = strncpy_from_user(p, (const char __user *) usymbol, KSYM_NAME_LEN);
2280 		if (err == KSYM_NAME_LEN)
2281 			err = -E2BIG;
2282 		if (err < 0)
2283 			goto error;
2284 		syms[i] = p;
2285 		p += err + 1;
2286 	}
2287 
2288 	us->syms = syms;
2289 	us->buf = buf;
2290 	return 0;
2291 
2292 error:
2293 	if (err) {
2294 		kvfree(syms);
2295 		kvfree(buf);
2296 	}
2297 	return err;
2298 }
2299 
free_user_syms(struct user_syms * us)2300 static void free_user_syms(struct user_syms *us)
2301 {
2302 	kvfree(us->syms);
2303 	kvfree(us->buf);
2304 }
2305 
bpf_kprobe_multi_link_release(struct bpf_link * link)2306 static void bpf_kprobe_multi_link_release(struct bpf_link *link)
2307 {
2308 	struct bpf_kprobe_multi_link *kmulti_link;
2309 
2310 	kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2311 	unregister_fprobe(&kmulti_link->fp);
2312 }
2313 
bpf_kprobe_multi_link_dealloc(struct bpf_link * link)2314 static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link)
2315 {
2316 	struct bpf_kprobe_multi_link *kmulti_link;
2317 
2318 	kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
2319 	kvfree(kmulti_link->addrs);
2320 	kvfree(kmulti_link->cookies);
2321 	kfree(kmulti_link);
2322 }
2323 
2324 static const struct bpf_link_ops bpf_kprobe_multi_link_lops = {
2325 	.release = bpf_kprobe_multi_link_release,
2326 	.dealloc = bpf_kprobe_multi_link_dealloc,
2327 };
2328 
bpf_kprobe_multi_cookie_swap(void * a,void * b,int size,const void * priv)2329 static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv)
2330 {
2331 	const struct bpf_kprobe_multi_link *link = priv;
2332 	unsigned long *addr_a = a, *addr_b = b;
2333 	u64 *cookie_a, *cookie_b;
2334 
2335 	cookie_a = link->cookies + (addr_a - link->addrs);
2336 	cookie_b = link->cookies + (addr_b - link->addrs);
2337 
2338 	/* swap addr_a/addr_b and cookie_a/cookie_b values */
2339 	swap(*addr_a, *addr_b);
2340 	swap(*cookie_a, *cookie_b);
2341 }
2342 
__bpf_kprobe_multi_cookie_cmp(const void * a,const void * b)2343 static int __bpf_kprobe_multi_cookie_cmp(const void *a, const void *b)
2344 {
2345 	const unsigned long *addr_a = a, *addr_b = b;
2346 
2347 	if (*addr_a == *addr_b)
2348 		return 0;
2349 	return *addr_a < *addr_b ? -1 : 1;
2350 }
2351 
bpf_kprobe_multi_cookie_cmp(const void * a,const void * b,const void * priv)2352 static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv)
2353 {
2354 	return __bpf_kprobe_multi_cookie_cmp(a, b);
2355 }
2356 
bpf_kprobe_multi_cookie(struct bpf_run_ctx * ctx)2357 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
2358 {
2359 	struct bpf_kprobe_multi_run_ctx *run_ctx;
2360 	struct bpf_kprobe_multi_link *link;
2361 	u64 *cookie, entry_ip;
2362 	unsigned long *addr;
2363 
2364 	if (WARN_ON_ONCE(!ctx))
2365 		return 0;
2366 	run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, run_ctx);
2367 	link = run_ctx->link;
2368 	if (!link->cookies)
2369 		return 0;
2370 	entry_ip = run_ctx->entry_ip;
2371 	addr = bsearch(&entry_ip, link->addrs, link->cnt, sizeof(entry_ip),
2372 		       __bpf_kprobe_multi_cookie_cmp);
2373 	if (!addr)
2374 		return 0;
2375 	cookie = link->cookies + (addr - link->addrs);
2376 	return *cookie;
2377 }
2378 
bpf_kprobe_multi_entry_ip(struct bpf_run_ctx * ctx)2379 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
2380 {
2381 	struct bpf_kprobe_multi_run_ctx *run_ctx;
2382 
2383 	run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, run_ctx);
2384 	return run_ctx->entry_ip;
2385 }
2386 
2387 static int
kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link * link,unsigned long entry_ip,struct pt_regs * regs)2388 kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
2389 			   unsigned long entry_ip, struct pt_regs *regs)
2390 {
2391 	struct bpf_kprobe_multi_run_ctx run_ctx = {
2392 		.link = link,
2393 		.entry_ip = entry_ip,
2394 	};
2395 	struct bpf_run_ctx *old_run_ctx;
2396 	int err;
2397 
2398 	if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
2399 		err = 0;
2400 		goto out;
2401 	}
2402 
2403 	migrate_disable();
2404 	rcu_read_lock();
2405 	old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
2406 	err = bpf_prog_run(link->link.prog, regs);
2407 	bpf_reset_run_ctx(old_run_ctx);
2408 	rcu_read_unlock();
2409 	migrate_enable();
2410 
2411  out:
2412 	__this_cpu_dec(bpf_prog_active);
2413 	return err;
2414 }
2415 
2416 static void
kprobe_multi_link_handler(struct fprobe * fp,unsigned long entry_ip,struct pt_regs * regs)2417 kprobe_multi_link_handler(struct fprobe *fp, unsigned long entry_ip,
2418 			  struct pt_regs *regs)
2419 {
2420 	struct bpf_kprobe_multi_link *link;
2421 
2422 	link = container_of(fp, struct bpf_kprobe_multi_link, fp);
2423 	kprobe_multi_link_prog_run(link, entry_ip, regs);
2424 }
2425 
symbols_cmp_r(const void * a,const void * b,const void * priv)2426 static int symbols_cmp_r(const void *a, const void *b, const void *priv)
2427 {
2428 	const char **str_a = (const char **) a;
2429 	const char **str_b = (const char **) b;
2430 
2431 	return strcmp(*str_a, *str_b);
2432 }
2433 
2434 struct multi_symbols_sort {
2435 	const char **funcs;
2436 	u64 *cookies;
2437 };
2438 
symbols_swap_r(void * a,void * b,int size,const void * priv)2439 static void symbols_swap_r(void *a, void *b, int size, const void *priv)
2440 {
2441 	const struct multi_symbols_sort *data = priv;
2442 	const char **name_a = a, **name_b = b;
2443 
2444 	swap(*name_a, *name_b);
2445 
2446 	/* If defined, swap also related cookies. */
2447 	if (data->cookies) {
2448 		u64 *cookie_a, *cookie_b;
2449 
2450 		cookie_a = data->cookies + (name_a - data->funcs);
2451 		cookie_b = data->cookies + (name_b - data->funcs);
2452 		swap(*cookie_a, *cookie_b);
2453 	}
2454 }
2455 
bpf_kprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)2456 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2457 {
2458 	struct bpf_kprobe_multi_link *link = NULL;
2459 	struct bpf_link_primer link_primer;
2460 	void __user *ucookies;
2461 	unsigned long *addrs;
2462 	u32 flags, cnt, size;
2463 	void __user *uaddrs;
2464 	u64 *cookies = NULL;
2465 	void __user *usyms;
2466 	int err;
2467 
2468 	/* no support for 32bit archs yet */
2469 	if (sizeof(u64) != sizeof(void *))
2470 		return -EOPNOTSUPP;
2471 
2472 	if (prog->expected_attach_type != BPF_TRACE_KPROBE_MULTI)
2473 		return -EINVAL;
2474 
2475 	flags = attr->link_create.kprobe_multi.flags;
2476 	if (flags & ~BPF_F_KPROBE_MULTI_RETURN)
2477 		return -EINVAL;
2478 
2479 	uaddrs = u64_to_user_ptr(attr->link_create.kprobe_multi.addrs);
2480 	usyms = u64_to_user_ptr(attr->link_create.kprobe_multi.syms);
2481 	if (!!uaddrs == !!usyms)
2482 		return -EINVAL;
2483 
2484 	cnt = attr->link_create.kprobe_multi.cnt;
2485 	if (!cnt)
2486 		return -EINVAL;
2487 
2488 	size = cnt * sizeof(*addrs);
2489 	addrs = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
2490 	if (!addrs)
2491 		return -ENOMEM;
2492 
2493 	ucookies = u64_to_user_ptr(attr->link_create.kprobe_multi.cookies);
2494 	if (ucookies) {
2495 		cookies = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
2496 		if (!cookies) {
2497 			err = -ENOMEM;
2498 			goto error;
2499 		}
2500 		if (copy_from_user(cookies, ucookies, size)) {
2501 			err = -EFAULT;
2502 			goto error;
2503 		}
2504 	}
2505 
2506 	if (uaddrs) {
2507 		if (copy_from_user(addrs, uaddrs, size)) {
2508 			err = -EFAULT;
2509 			goto error;
2510 		}
2511 	} else {
2512 		struct multi_symbols_sort data = {
2513 			.cookies = cookies,
2514 		};
2515 		struct user_syms us;
2516 
2517 		err = copy_user_syms(&us, usyms, cnt);
2518 		if (err)
2519 			goto error;
2520 
2521 		if (cookies)
2522 			data.funcs = us.syms;
2523 
2524 		sort_r(us.syms, cnt, sizeof(*us.syms), symbols_cmp_r,
2525 		       symbols_swap_r, &data);
2526 
2527 		err = ftrace_lookup_symbols(us.syms, cnt, addrs);
2528 		free_user_syms(&us);
2529 		if (err)
2530 			goto error;
2531 	}
2532 
2533 	link = kzalloc(sizeof(*link), GFP_KERNEL);
2534 	if (!link) {
2535 		err = -ENOMEM;
2536 		goto error;
2537 	}
2538 
2539 	bpf_link_init(&link->link, BPF_LINK_TYPE_KPROBE_MULTI,
2540 		      &bpf_kprobe_multi_link_lops, prog);
2541 
2542 	err = bpf_link_prime(&link->link, &link_primer);
2543 	if (err)
2544 		goto error;
2545 
2546 	if (flags & BPF_F_KPROBE_MULTI_RETURN)
2547 		link->fp.exit_handler = kprobe_multi_link_handler;
2548 	else
2549 		link->fp.entry_handler = kprobe_multi_link_handler;
2550 
2551 	link->addrs = addrs;
2552 	link->cookies = cookies;
2553 	link->cnt = cnt;
2554 
2555 	if (cookies) {
2556 		/*
2557 		 * Sorting addresses will trigger sorting cookies as well
2558 		 * (check bpf_kprobe_multi_cookie_swap). This way we can
2559 		 * find cookie based on the address in bpf_get_attach_cookie
2560 		 * helper.
2561 		 */
2562 		sort_r(addrs, cnt, sizeof(*addrs),
2563 		       bpf_kprobe_multi_cookie_cmp,
2564 		       bpf_kprobe_multi_cookie_swap,
2565 		       link);
2566 	}
2567 
2568 	err = register_fprobe_ips(&link->fp, addrs, cnt);
2569 	if (err) {
2570 		bpf_link_cleanup(&link_primer);
2571 		return err;
2572 	}
2573 
2574 	return bpf_link_settle(&link_primer);
2575 
2576 error:
2577 	kfree(link);
2578 	kvfree(addrs);
2579 	kvfree(cookies);
2580 	return err;
2581 }
2582 #else /* !CONFIG_FPROBE */
bpf_kprobe_multi_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)2583 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2584 {
2585 	return -EOPNOTSUPP;
2586 }
bpf_kprobe_multi_cookie(struct bpf_run_ctx * ctx)2587 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
2588 {
2589 	return 0;
2590 }
bpf_kprobe_multi_entry_ip(struct bpf_run_ctx * ctx)2591 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
2592 {
2593 	return 0;
2594 }
2595 #endif
2596