kernel/trace/bpf_trace.c

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