1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2020 Facebook */ 3 #include <vmlinux.h> 4 #include <bpf/bpf_core_read.h> 5 #include <bpf/bpf_helpers.h> 6 #include <bpf/bpf_tracing.h> 7 8 #include "profiler.h" 9 10 #ifndef NULL 11 #define NULL 0 12 #endif 13 14 #define O_WRONLY 00000001 15 #define O_RDWR 00000002 16 #define O_DIRECTORY 00200000 17 #define __O_TMPFILE 020000000 18 #define O_TMPFILE (__O_TMPFILE | O_DIRECTORY) 19 #define MAX_ERRNO 4095 20 #define S_IFMT 00170000 21 #define S_IFSOCK 0140000 22 #define S_IFLNK 0120000 23 #define S_IFREG 0100000 24 #define S_IFBLK 0060000 25 #define S_IFDIR 0040000 26 #define S_IFCHR 0020000 27 #define S_IFIFO 0010000 28 #define S_ISUID 0004000 29 #define S_ISGID 0002000 30 #define S_ISVTX 0001000 31 #define S_ISLNK(m) (((m)&S_IFMT) == S_IFLNK) 32 #define S_ISDIR(m) (((m)&S_IFMT) == S_IFDIR) 33 #define S_ISCHR(m) (((m)&S_IFMT) == S_IFCHR) 34 #define S_ISBLK(m) (((m)&S_IFMT) == S_IFBLK) 35 #define S_ISFIFO(m) (((m)&S_IFMT) == S_IFIFO) 36 #define S_ISSOCK(m) (((m)&S_IFMT) == S_IFSOCK) 37 #define IS_ERR_VALUE(x) (unsigned long)(void*)(x) >= (unsigned long)-MAX_ERRNO 38 39 #define KILL_DATA_ARRAY_SIZE 8 40 41 struct var_kill_data_arr_t { 42 struct var_kill_data_t array[KILL_DATA_ARRAY_SIZE]; 43 }; 44 45 union any_profiler_data_t { 46 struct var_exec_data_t var_exec; 47 struct var_kill_data_t var_kill; 48 struct var_sysctl_data_t var_sysctl; 49 struct var_filemod_data_t var_filemod; 50 struct var_fork_data_t var_fork; 51 struct var_kill_data_arr_t var_kill_data_arr; 52 }; 53 54 volatile struct profiler_config_struct bpf_config = {}; 55 56 #define FETCH_CGROUPS_FROM_BPF (bpf_config.fetch_cgroups_from_bpf) 57 #define CGROUP_FS_INODE (bpf_config.cgroup_fs_inode) 58 #define CGROUP_LOGIN_SESSION_INODE \ 59 (bpf_config.cgroup_login_session_inode) 60 #define KILL_SIGNALS (bpf_config.kill_signals_mask) 61 #define STALE_INFO (bpf_config.stale_info_secs) 62 #define INODE_FILTER (bpf_config.inode_filter) 63 #define READ_ENVIRON_FROM_EXEC (bpf_config.read_environ_from_exec) 64 #define ENABLE_CGROUP_V1_RESOLVER (bpf_config.enable_cgroup_v1_resolver) 65 66 struct kernfs_iattrs___52 { 67 struct iattr ia_iattr; 68 }; 69 70 struct kernfs_node___52 { 71 union /* kernfs_node_id */ { 72 struct { 73 u32 ino; 74 u32 generation; 75 }; 76 u64 id; 77 } id; 78 }; 79 80 struct { 81 __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); 82 __uint(max_entries, 1); 83 __type(key, u32); 84 __type(value, union any_profiler_data_t); 85 } data_heap SEC(".maps"); 86 87 struct { 88 __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); 89 __uint(key_size, sizeof(int)); 90 __uint(value_size, sizeof(int)); 91 } events SEC(".maps"); 92 93 struct { 94 __uint(type, BPF_MAP_TYPE_HASH); 95 __uint(max_entries, KILL_DATA_ARRAY_SIZE); 96 __type(key, u32); 97 __type(value, struct var_kill_data_arr_t); 98 } var_tpid_to_data SEC(".maps"); 99 100 struct { 101 __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); 102 __uint(max_entries, profiler_bpf_max_function_id); 103 __type(key, u32); 104 __type(value, struct bpf_func_stats_data); 105 } bpf_func_stats SEC(".maps"); 106 107 struct { 108 __uint(type, BPF_MAP_TYPE_HASH); 109 __type(key, u32); 110 __type(value, bool); 111 __uint(max_entries, 16); 112 } allowed_devices SEC(".maps"); 113 114 struct { 115 __uint(type, BPF_MAP_TYPE_HASH); 116 __type(key, u64); 117 __type(value, bool); 118 __uint(max_entries, 1024); 119 } allowed_file_inodes SEC(".maps"); 120 121 struct { 122 __uint(type, BPF_MAP_TYPE_HASH); 123 __type(key, u64); 124 __type(value, bool); 125 __uint(max_entries, 1024); 126 } allowed_directory_inodes SEC(".maps"); 127 128 struct { 129 __uint(type, BPF_MAP_TYPE_HASH); 130 __type(key, u32); 131 __type(value, bool); 132 __uint(max_entries, 16); 133 } disallowed_exec_inodes SEC(".maps"); 134 135 #ifndef ARRAY_SIZE 136 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0])) 137 #endif 138 139 static INLINE bool IS_ERR(const void* ptr) 140 { 141 return IS_ERR_VALUE((unsigned long)ptr); 142 } 143 144 static INLINE u32 get_userspace_pid() 145 { 146 return bpf_get_current_pid_tgid() >> 32; 147 } 148 149 static INLINE bool is_init_process(u32 tgid) 150 { 151 return tgid == 1 || tgid == 0; 152 } 153 154 static INLINE unsigned long 155 probe_read_lim(void* dst, void* src, unsigned long len, unsigned long max) 156 { 157 len = len < max ? len : max; 158 if (len > 1) { 159 if (bpf_probe_read(dst, len, src)) 160 return 0; 161 } else if (len == 1) { 162 if (bpf_probe_read(dst, 1, src)) 163 return 0; 164 } 165 return len; 166 } 167 168 static INLINE int get_var_spid_index(struct var_kill_data_arr_t* arr_struct, 169 int spid) 170 { 171 #ifdef UNROLL 172 #pragma unroll 173 #endif 174 for (int i = 0; i < ARRAY_SIZE(arr_struct->array); i++) 175 if (arr_struct->array[i].meta.pid == spid) 176 return i; 177 return -1; 178 } 179 180 static INLINE void populate_ancestors(struct task_struct* task, 181 struct ancestors_data_t* ancestors_data) 182 { 183 struct task_struct* parent = task; 184 u32 num_ancestors, ppid; 185 186 ancestors_data->num_ancestors = 0; 187 #ifdef UNROLL 188 #pragma unroll 189 #endif 190 for (num_ancestors = 0; num_ancestors < MAX_ANCESTORS; num_ancestors++) { 191 parent = BPF_CORE_READ(parent, real_parent); 192 if (parent == NULL) 193 break; 194 ppid = BPF_CORE_READ(parent, tgid); 195 if (is_init_process(ppid)) 196 break; 197 ancestors_data->ancestor_pids[num_ancestors] = ppid; 198 ancestors_data->ancestor_exec_ids[num_ancestors] = 199 BPF_CORE_READ(parent, self_exec_id); 200 ancestors_data->ancestor_start_times[num_ancestors] = 201 BPF_CORE_READ(parent, start_time); 202 ancestors_data->num_ancestors = num_ancestors; 203 } 204 } 205 206 static INLINE void* read_full_cgroup_path(struct kernfs_node* cgroup_node, 207 struct kernfs_node* cgroup_root_node, 208 void* payload, 209 int* root_pos) 210 { 211 void* payload_start = payload; 212 size_t filepart_length; 213 214 #ifdef UNROLL 215 #pragma unroll 216 #endif 217 for (int i = 0; i < MAX_CGROUPS_PATH_DEPTH; i++) { 218 filepart_length = 219 bpf_probe_read_str(payload, MAX_PATH, BPF_CORE_READ(cgroup_node, name)); 220 if (!cgroup_node) 221 return payload; 222 if (cgroup_node == cgroup_root_node) 223 *root_pos = payload - payload_start; 224 if (filepart_length <= MAX_PATH) { 225 barrier_var(filepart_length); 226 payload += filepart_length; 227 } 228 cgroup_node = BPF_CORE_READ(cgroup_node, parent); 229 } 230 return payload; 231 } 232 233 static ino_t get_inode_from_kernfs(struct kernfs_node* node) 234 { 235 struct kernfs_node___52* node52 = (void*)node; 236 237 if (bpf_core_field_exists(node52->id.ino)) { 238 barrier_var(node52); 239 return BPF_CORE_READ(node52, id.ino); 240 } else { 241 barrier_var(node); 242 return (u64)BPF_CORE_READ(node, id); 243 } 244 } 245 246 extern bool CONFIG_CGROUP_PIDS __kconfig __weak; 247 enum cgroup_subsys_id___local { 248 pids_cgrp_id___local = 123, /* value doesn't matter */ 249 }; 250 251 static INLINE void* populate_cgroup_info(struct cgroup_data_t* cgroup_data, 252 struct task_struct* task, 253 void* payload) 254 { 255 struct kernfs_node* root_kernfs = 256 BPF_CORE_READ(task, nsproxy, cgroup_ns, root_cset, dfl_cgrp, kn); 257 struct kernfs_node* proc_kernfs = BPF_CORE_READ(task, cgroups, dfl_cgrp, kn); 258 259 if (ENABLE_CGROUP_V1_RESOLVER && CONFIG_CGROUP_PIDS) { 260 int cgrp_id = bpf_core_enum_value(enum cgroup_subsys_id___local, 261 pids_cgrp_id___local); 262 #ifdef UNROLL 263 #pragma unroll 264 #endif 265 for (int i = 0; i < CGROUP_SUBSYS_COUNT; i++) { 266 struct cgroup_subsys_state* subsys = 267 BPF_CORE_READ(task, cgroups, subsys[i]); 268 if (subsys != NULL) { 269 int subsys_id = BPF_CORE_READ(subsys, ss, id); 270 if (subsys_id == cgrp_id) { 271 proc_kernfs = BPF_CORE_READ(subsys, cgroup, kn); 272 root_kernfs = BPF_CORE_READ(subsys, ss, root, kf_root, kn); 273 break; 274 } 275 } 276 } 277 } 278 279 cgroup_data->cgroup_root_inode = get_inode_from_kernfs(root_kernfs); 280 cgroup_data->cgroup_proc_inode = get_inode_from_kernfs(proc_kernfs); 281 282 if (bpf_core_field_exists(root_kernfs->iattr->ia_mtime)) { 283 cgroup_data->cgroup_root_mtime = 284 BPF_CORE_READ(root_kernfs, iattr, ia_mtime.tv_nsec); 285 cgroup_data->cgroup_proc_mtime = 286 BPF_CORE_READ(proc_kernfs, iattr, ia_mtime.tv_nsec); 287 } else { 288 struct kernfs_iattrs___52* root_iattr = 289 (struct kernfs_iattrs___52*)BPF_CORE_READ(root_kernfs, iattr); 290 cgroup_data->cgroup_root_mtime = 291 BPF_CORE_READ(root_iattr, ia_iattr.ia_mtime.tv_nsec); 292 293 struct kernfs_iattrs___52* proc_iattr = 294 (struct kernfs_iattrs___52*)BPF_CORE_READ(proc_kernfs, iattr); 295 cgroup_data->cgroup_proc_mtime = 296 BPF_CORE_READ(proc_iattr, ia_iattr.ia_mtime.tv_nsec); 297 } 298 299 cgroup_data->cgroup_root_length = 0; 300 cgroup_data->cgroup_proc_length = 0; 301 cgroup_data->cgroup_full_length = 0; 302 303 size_t cgroup_root_length = 304 bpf_probe_read_str(payload, MAX_PATH, BPF_CORE_READ(root_kernfs, name)); 305 barrier_var(cgroup_root_length); 306 if (cgroup_root_length <= MAX_PATH) { 307 barrier_var(cgroup_root_length); 308 cgroup_data->cgroup_root_length = cgroup_root_length; 309 payload += cgroup_root_length; 310 } 311 312 size_t cgroup_proc_length = 313 bpf_probe_read_str(payload, MAX_PATH, BPF_CORE_READ(proc_kernfs, name)); 314 barrier_var(cgroup_proc_length); 315 if (cgroup_proc_length <= MAX_PATH) { 316 barrier_var(cgroup_proc_length); 317 cgroup_data->cgroup_proc_length = cgroup_proc_length; 318 payload += cgroup_proc_length; 319 } 320 321 if (FETCH_CGROUPS_FROM_BPF) { 322 cgroup_data->cgroup_full_path_root_pos = -1; 323 void* payload_end_pos = read_full_cgroup_path(proc_kernfs, root_kernfs, payload, 324 &cgroup_data->cgroup_full_path_root_pos); 325 cgroup_data->cgroup_full_length = payload_end_pos - payload; 326 payload = payload_end_pos; 327 } 328 329 return (void*)payload; 330 } 331 332 static INLINE void* populate_var_metadata(struct var_metadata_t* metadata, 333 struct task_struct* task, 334 u32 pid, void* payload) 335 { 336 u64 uid_gid = bpf_get_current_uid_gid(); 337 338 metadata->uid = (u32)uid_gid; 339 metadata->gid = uid_gid >> 32; 340 metadata->pid = pid; 341 metadata->exec_id = BPF_CORE_READ(task, self_exec_id); 342 metadata->start_time = BPF_CORE_READ(task, start_time); 343 metadata->comm_length = 0; 344 345 size_t comm_length = bpf_core_read_str(payload, TASK_COMM_LEN, &task->comm); 346 barrier_var(comm_length); 347 if (comm_length <= TASK_COMM_LEN) { 348 barrier_var(comm_length); 349 metadata->comm_length = comm_length; 350 payload += comm_length; 351 } 352 353 return (void*)payload; 354 } 355 356 static INLINE struct var_kill_data_t* 357 get_var_kill_data(struct pt_regs* ctx, int spid, int tpid, int sig) 358 { 359 int zero = 0; 360 struct var_kill_data_t* kill_data = bpf_map_lookup_elem(&data_heap, &zero); 361 362 if (kill_data == NULL) 363 return NULL; 364 struct task_struct* task = (struct task_struct*)bpf_get_current_task(); 365 366 void* payload = populate_var_metadata(&kill_data->meta, task, spid, kill_data->payload); 367 payload = populate_cgroup_info(&kill_data->cgroup_data, task, payload); 368 size_t payload_length = payload - (void*)kill_data->payload; 369 kill_data->payload_length = payload_length; 370 populate_ancestors(task, &kill_data->ancestors_info); 371 kill_data->meta.type = KILL_EVENT; 372 kill_data->kill_target_pid = tpid; 373 kill_data->kill_sig = sig; 374 kill_data->kill_count = 1; 375 kill_data->last_kill_time = bpf_ktime_get_ns(); 376 return kill_data; 377 } 378 379 static INLINE int trace_var_sys_kill(void* ctx, int tpid, int sig) 380 { 381 if ((KILL_SIGNALS & (1ULL << sig)) == 0) 382 return 0; 383 384 u32 spid = get_userspace_pid(); 385 struct var_kill_data_arr_t* arr_struct = bpf_map_lookup_elem(&var_tpid_to_data, &tpid); 386 387 if (arr_struct == NULL) { 388 struct var_kill_data_t* kill_data = get_var_kill_data(ctx, spid, tpid, sig); 389 int zero = 0; 390 391 if (kill_data == NULL) 392 return 0; 393 arr_struct = bpf_map_lookup_elem(&data_heap, &zero); 394 if (arr_struct == NULL) 395 return 0; 396 bpf_probe_read(&arr_struct->array[0], sizeof(arr_struct->array[0]), kill_data); 397 } else { 398 int index = get_var_spid_index(arr_struct, spid); 399 400 if (index == -1) { 401 struct var_kill_data_t* kill_data = 402 get_var_kill_data(ctx, spid, tpid, sig); 403 if (kill_data == NULL) 404 return 0; 405 #ifdef UNROLL 406 #pragma unroll 407 #endif 408 for (int i = 0; i < ARRAY_SIZE(arr_struct->array); i++) 409 if (arr_struct->array[i].meta.pid == 0) { 410 bpf_probe_read(&arr_struct->array[i], 411 sizeof(arr_struct->array[i]), kill_data); 412 bpf_map_update_elem(&var_tpid_to_data, &tpid, 413 arr_struct, 0); 414 415 return 0; 416 } 417 return 0; 418 } 419 420 struct var_kill_data_t* kill_data = &arr_struct->array[index]; 421 422 u64 delta_sec = 423 (bpf_ktime_get_ns() - kill_data->last_kill_time) / 1000000000; 424 425 if (delta_sec < STALE_INFO) { 426 kill_data->kill_count++; 427 kill_data->last_kill_time = bpf_ktime_get_ns(); 428 bpf_probe_read(&arr_struct->array[index], 429 sizeof(arr_struct->array[index]), 430 kill_data); 431 } else { 432 struct var_kill_data_t* kill_data = 433 get_var_kill_data(ctx, spid, tpid, sig); 434 if (kill_data == NULL) 435 return 0; 436 bpf_probe_read(&arr_struct->array[index], 437 sizeof(arr_struct->array[index]), 438 kill_data); 439 } 440 } 441 bpf_map_update_elem(&var_tpid_to_data, &tpid, arr_struct, 0); 442 return 0; 443 } 444 445 static INLINE void bpf_stats_enter(struct bpf_func_stats_ctx* bpf_stat_ctx, 446 enum bpf_function_id func_id) 447 { 448 int func_id_key = func_id; 449 450 bpf_stat_ctx->start_time_ns = bpf_ktime_get_ns(); 451 bpf_stat_ctx->bpf_func_stats_data_val = 452 bpf_map_lookup_elem(&bpf_func_stats, &func_id_key); 453 if (bpf_stat_ctx->bpf_func_stats_data_val) 454 bpf_stat_ctx->bpf_func_stats_data_val->num_executions++; 455 } 456 457 static INLINE void bpf_stats_exit(struct bpf_func_stats_ctx* bpf_stat_ctx) 458 { 459 if (bpf_stat_ctx->bpf_func_stats_data_val) 460 bpf_stat_ctx->bpf_func_stats_data_val->time_elapsed_ns += 461 bpf_ktime_get_ns() - bpf_stat_ctx->start_time_ns; 462 } 463 464 static INLINE void 465 bpf_stats_pre_submit_var_perf_event(struct bpf_func_stats_ctx* bpf_stat_ctx, 466 struct var_metadata_t* meta) 467 { 468 if (bpf_stat_ctx->bpf_func_stats_data_val) { 469 bpf_stat_ctx->bpf_func_stats_data_val->num_perf_events++; 470 meta->bpf_stats_num_perf_events = 471 bpf_stat_ctx->bpf_func_stats_data_val->num_perf_events; 472 } 473 meta->bpf_stats_start_ktime_ns = bpf_stat_ctx->start_time_ns; 474 meta->cpu_id = bpf_get_smp_processor_id(); 475 } 476 477 static INLINE size_t 478 read_absolute_file_path_from_dentry(struct dentry* filp_dentry, void* payload) 479 { 480 size_t length = 0; 481 size_t filepart_length; 482 struct dentry* parent_dentry; 483 484 #ifdef UNROLL 485 #pragma unroll 486 #endif 487 for (int i = 0; i < MAX_PATH_DEPTH; i++) { 488 filepart_length = bpf_probe_read_str(payload, MAX_PATH, 489 BPF_CORE_READ(filp_dentry, d_name.name)); 490 barrier_var(filepart_length); 491 if (filepart_length > MAX_PATH) 492 break; 493 barrier_var(filepart_length); 494 payload += filepart_length; 495 length += filepart_length; 496 497 parent_dentry = BPF_CORE_READ(filp_dentry, d_parent); 498 if (filp_dentry == parent_dentry) 499 break; 500 filp_dentry = parent_dentry; 501 } 502 503 return length; 504 } 505 506 static INLINE bool 507 is_ancestor_in_allowed_inodes(struct dentry* filp_dentry) 508 { 509 struct dentry* parent_dentry; 510 #ifdef UNROLL 511 #pragma unroll 512 #endif 513 for (int i = 0; i < MAX_PATH_DEPTH; i++) { 514 u64 dir_ino = BPF_CORE_READ(filp_dentry, d_inode, i_ino); 515 bool* allowed_dir = bpf_map_lookup_elem(&allowed_directory_inodes, &dir_ino); 516 517 if (allowed_dir != NULL) 518 return true; 519 parent_dentry = BPF_CORE_READ(filp_dentry, d_parent); 520 if (filp_dentry == parent_dentry) 521 break; 522 filp_dentry = parent_dentry; 523 } 524 return false; 525 } 526 527 static INLINE bool is_dentry_allowed_for_filemod(struct dentry* file_dentry, 528 u32* device_id, 529 u64* file_ino) 530 { 531 u32 dev_id = BPF_CORE_READ(file_dentry, d_sb, s_dev); 532 *device_id = dev_id; 533 bool* allowed_device = bpf_map_lookup_elem(&allowed_devices, &dev_id); 534 535 if (allowed_device == NULL) 536 return false; 537 538 u64 ino = BPF_CORE_READ(file_dentry, d_inode, i_ino); 539 *file_ino = ino; 540 bool* allowed_file = bpf_map_lookup_elem(&allowed_file_inodes, &ino); 541 542 if (allowed_file == NULL) 543 if (!is_ancestor_in_allowed_inodes(BPF_CORE_READ(file_dentry, d_parent))) 544 return false; 545 return true; 546 } 547 548 SEC("kprobe/proc_sys_write") 549 ssize_t BPF_KPROBE(kprobe__proc_sys_write, 550 struct file* filp, const char* buf, 551 size_t count, loff_t* ppos) 552 { 553 struct bpf_func_stats_ctx stats_ctx; 554 bpf_stats_enter(&stats_ctx, profiler_bpf_proc_sys_write); 555 556 u32 pid = get_userspace_pid(); 557 int zero = 0; 558 struct var_sysctl_data_t* sysctl_data = 559 bpf_map_lookup_elem(&data_heap, &zero); 560 if (!sysctl_data) 561 goto out; 562 563 struct task_struct* task = (struct task_struct*)bpf_get_current_task(); 564 sysctl_data->meta.type = SYSCTL_EVENT; 565 void* payload = populate_var_metadata(&sysctl_data->meta, task, pid, sysctl_data->payload); 566 payload = populate_cgroup_info(&sysctl_data->cgroup_data, task, payload); 567 568 populate_ancestors(task, &sysctl_data->ancestors_info); 569 570 sysctl_data->sysctl_val_length = 0; 571 sysctl_data->sysctl_path_length = 0; 572 573 size_t sysctl_val_length = bpf_probe_read_str(payload, CTL_MAXNAME, buf); 574 barrier_var(sysctl_val_length); 575 if (sysctl_val_length <= CTL_MAXNAME) { 576 barrier_var(sysctl_val_length); 577 sysctl_data->sysctl_val_length = sysctl_val_length; 578 payload += sysctl_val_length; 579 } 580 581 size_t sysctl_path_length = bpf_probe_read_str(payload, MAX_PATH, 582 BPF_CORE_READ(filp, f_path.dentry, d_name.name)); 583 barrier_var(sysctl_path_length); 584 if (sysctl_path_length <= MAX_PATH) { 585 barrier_var(sysctl_path_length); 586 sysctl_data->sysctl_path_length = sysctl_path_length; 587 payload += sysctl_path_length; 588 } 589 590 bpf_stats_pre_submit_var_perf_event(&stats_ctx, &sysctl_data->meta); 591 unsigned long data_len = payload - (void*)sysctl_data; 592 data_len = data_len > sizeof(struct var_sysctl_data_t) 593 ? sizeof(struct var_sysctl_data_t) 594 : data_len; 595 bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, sysctl_data, data_len); 596 out: 597 bpf_stats_exit(&stats_ctx); 598 return 0; 599 } 600 601 SEC("tracepoint/syscalls/sys_enter_kill") 602 int tracepoint__syscalls__sys_enter_kill(struct trace_event_raw_sys_enter* ctx) 603 { 604 struct bpf_func_stats_ctx stats_ctx; 605 606 bpf_stats_enter(&stats_ctx, profiler_bpf_sys_enter_kill); 607 int pid = ctx->args[0]; 608 int sig = ctx->args[1]; 609 int ret = trace_var_sys_kill(ctx, pid, sig); 610 bpf_stats_exit(&stats_ctx); 611 return ret; 612 }; 613 614 SEC("raw_tracepoint/sched_process_exit") 615 int raw_tracepoint__sched_process_exit(void* ctx) 616 { 617 int zero = 0; 618 struct bpf_func_stats_ctx stats_ctx; 619 bpf_stats_enter(&stats_ctx, profiler_bpf_sched_process_exit); 620 621 u32 tpid = get_userspace_pid(); 622 623 struct var_kill_data_arr_t* arr_struct = bpf_map_lookup_elem(&var_tpid_to_data, &tpid); 624 struct var_kill_data_t* kill_data = bpf_map_lookup_elem(&data_heap, &zero); 625 626 if (arr_struct == NULL || kill_data == NULL) 627 goto out; 628 629 struct task_struct* task = (struct task_struct*)bpf_get_current_task(); 630 struct kernfs_node* proc_kernfs = BPF_CORE_READ(task, cgroups, dfl_cgrp, kn); 631 632 #ifdef UNROLL 633 #pragma unroll 634 #endif 635 for (int i = 0; i < ARRAY_SIZE(arr_struct->array); i++) { 636 struct var_kill_data_t* past_kill_data = &arr_struct->array[i]; 637 638 if (past_kill_data != NULL && past_kill_data->kill_target_pid == tpid) { 639 bpf_probe_read(kill_data, sizeof(*past_kill_data), past_kill_data); 640 void* payload = kill_data->payload; 641 size_t offset = kill_data->payload_length; 642 if (offset >= MAX_METADATA_PAYLOAD_LEN + MAX_CGROUP_PAYLOAD_LEN) 643 return 0; 644 payload += offset; 645 646 kill_data->kill_target_name_length = 0; 647 kill_data->kill_target_cgroup_proc_length = 0; 648 649 size_t comm_length = bpf_core_read_str(payload, TASK_COMM_LEN, &task->comm); 650 barrier_var(comm_length); 651 if (comm_length <= TASK_COMM_LEN) { 652 barrier_var(comm_length); 653 kill_data->kill_target_name_length = comm_length; 654 payload += comm_length; 655 } 656 657 size_t cgroup_proc_length = bpf_probe_read_str(payload, KILL_TARGET_LEN, 658 BPF_CORE_READ(proc_kernfs, name)); 659 barrier_var(cgroup_proc_length); 660 if (cgroup_proc_length <= KILL_TARGET_LEN) { 661 barrier_var(cgroup_proc_length); 662 kill_data->kill_target_cgroup_proc_length = cgroup_proc_length; 663 payload += cgroup_proc_length; 664 } 665 666 bpf_stats_pre_submit_var_perf_event(&stats_ctx, &kill_data->meta); 667 unsigned long data_len = (void*)payload - (void*)kill_data; 668 data_len = data_len > sizeof(struct var_kill_data_t) 669 ? sizeof(struct var_kill_data_t) 670 : data_len; 671 bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, kill_data, data_len); 672 } 673 } 674 bpf_map_delete_elem(&var_tpid_to_data, &tpid); 675 out: 676 bpf_stats_exit(&stats_ctx); 677 return 0; 678 } 679 680 SEC("raw_tracepoint/sched_process_exec") 681 int raw_tracepoint__sched_process_exec(struct bpf_raw_tracepoint_args* ctx) 682 { 683 struct bpf_func_stats_ctx stats_ctx; 684 bpf_stats_enter(&stats_ctx, profiler_bpf_sched_process_exec); 685 686 struct linux_binprm* bprm = (struct linux_binprm*)ctx->args[2]; 687 u64 inode = BPF_CORE_READ(bprm, file, f_inode, i_ino); 688 689 bool* should_filter_binprm = bpf_map_lookup_elem(&disallowed_exec_inodes, &inode); 690 if (should_filter_binprm != NULL) 691 goto out; 692 693 int zero = 0; 694 struct var_exec_data_t* proc_exec_data = bpf_map_lookup_elem(&data_heap, &zero); 695 if (!proc_exec_data) 696 goto out; 697 698 if (INODE_FILTER && inode != INODE_FILTER) 699 return 0; 700 701 u32 pid = get_userspace_pid(); 702 struct task_struct* task = (struct task_struct*)bpf_get_current_task(); 703 704 proc_exec_data->meta.type = EXEC_EVENT; 705 proc_exec_data->bin_path_length = 0; 706 proc_exec_data->cmdline_length = 0; 707 proc_exec_data->environment_length = 0; 708 void* payload = populate_var_metadata(&proc_exec_data->meta, task, pid, 709 proc_exec_data->payload); 710 payload = populate_cgroup_info(&proc_exec_data->cgroup_data, task, payload); 711 712 struct task_struct* parent_task = BPF_CORE_READ(task, real_parent); 713 proc_exec_data->parent_pid = BPF_CORE_READ(parent_task, tgid); 714 proc_exec_data->parent_uid = BPF_CORE_READ(parent_task, real_cred, uid.val); 715 proc_exec_data->parent_exec_id = BPF_CORE_READ(parent_task, self_exec_id); 716 proc_exec_data->parent_start_time = BPF_CORE_READ(parent_task, start_time); 717 718 const char* filename = BPF_CORE_READ(bprm, filename); 719 size_t bin_path_length = bpf_probe_read_str(payload, MAX_FILENAME_LEN, filename); 720 barrier_var(bin_path_length); 721 if (bin_path_length <= MAX_FILENAME_LEN) { 722 barrier_var(bin_path_length); 723 proc_exec_data->bin_path_length = bin_path_length; 724 payload += bin_path_length; 725 } 726 727 void* arg_start = (void*)BPF_CORE_READ(task, mm, arg_start); 728 void* arg_end = (void*)BPF_CORE_READ(task, mm, arg_end); 729 unsigned int cmdline_length = probe_read_lim(payload, arg_start, 730 arg_end - arg_start, MAX_ARGS_LEN); 731 732 if (cmdline_length <= MAX_ARGS_LEN) { 733 barrier_var(cmdline_length); 734 proc_exec_data->cmdline_length = cmdline_length; 735 payload += cmdline_length; 736 } 737 738 if (READ_ENVIRON_FROM_EXEC) { 739 void* env_start = (void*)BPF_CORE_READ(task, mm, env_start); 740 void* env_end = (void*)BPF_CORE_READ(task, mm, env_end); 741 unsigned long env_len = probe_read_lim(payload, env_start, 742 env_end - env_start, MAX_ENVIRON_LEN); 743 if (cmdline_length <= MAX_ENVIRON_LEN) { 744 proc_exec_data->environment_length = env_len; 745 payload += env_len; 746 } 747 } 748 749 bpf_stats_pre_submit_var_perf_event(&stats_ctx, &proc_exec_data->meta); 750 unsigned long data_len = payload - (void*)proc_exec_data; 751 data_len = data_len > sizeof(struct var_exec_data_t) 752 ? sizeof(struct var_exec_data_t) 753 : data_len; 754 bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, proc_exec_data, data_len); 755 out: 756 bpf_stats_exit(&stats_ctx); 757 return 0; 758 } 759 760 SEC("kretprobe/do_filp_open") 761 int kprobe_ret__do_filp_open(struct pt_regs* ctx) 762 { 763 struct bpf_func_stats_ctx stats_ctx; 764 bpf_stats_enter(&stats_ctx, profiler_bpf_do_filp_open_ret); 765 766 struct file* filp = (struct file*)PT_REGS_RC_CORE(ctx); 767 768 if (filp == NULL || IS_ERR(filp)) 769 goto out; 770 unsigned int flags = BPF_CORE_READ(filp, f_flags); 771 if ((flags & (O_RDWR | O_WRONLY)) == 0) 772 goto out; 773 if ((flags & O_TMPFILE) > 0) 774 goto out; 775 struct inode* file_inode = BPF_CORE_READ(filp, f_inode); 776 umode_t mode = BPF_CORE_READ(file_inode, i_mode); 777 if (S_ISDIR(mode) || S_ISCHR(mode) || S_ISBLK(mode) || S_ISFIFO(mode) || 778 S_ISSOCK(mode)) 779 goto out; 780 781 struct dentry* filp_dentry = BPF_CORE_READ(filp, f_path.dentry); 782 u32 device_id = 0; 783 u64 file_ino = 0; 784 if (!is_dentry_allowed_for_filemod(filp_dentry, &device_id, &file_ino)) 785 goto out; 786 787 int zero = 0; 788 struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero); 789 if (!filemod_data) 790 goto out; 791 792 u32 pid = get_userspace_pid(); 793 struct task_struct* task = (struct task_struct*)bpf_get_current_task(); 794 795 filemod_data->meta.type = FILEMOD_EVENT; 796 filemod_data->fmod_type = FMOD_OPEN; 797 filemod_data->dst_flags = flags; 798 filemod_data->src_inode = 0; 799 filemod_data->dst_inode = file_ino; 800 filemod_data->src_device_id = 0; 801 filemod_data->dst_device_id = device_id; 802 filemod_data->src_filepath_length = 0; 803 filemod_data->dst_filepath_length = 0; 804 805 void* payload = populate_var_metadata(&filemod_data->meta, task, pid, 806 filemod_data->payload); 807 payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload); 808 809 size_t len = read_absolute_file_path_from_dentry(filp_dentry, payload); 810 barrier_var(len); 811 if (len <= MAX_FILEPATH_LENGTH) { 812 barrier_var(len); 813 payload += len; 814 filemod_data->dst_filepath_length = len; 815 } 816 bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta); 817 unsigned long data_len = payload - (void*)filemod_data; 818 data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len; 819 bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len); 820 out: 821 bpf_stats_exit(&stats_ctx); 822 return 0; 823 } 824 825 SEC("kprobe/vfs_link") 826 int BPF_KPROBE(kprobe__vfs_link, 827 struct dentry* old_dentry, struct inode* dir, 828 struct dentry* new_dentry, struct inode** delegated_inode) 829 { 830 struct bpf_func_stats_ctx stats_ctx; 831 bpf_stats_enter(&stats_ctx, profiler_bpf_vfs_link); 832 833 u32 src_device_id = 0; 834 u64 src_file_ino = 0; 835 u32 dst_device_id = 0; 836 u64 dst_file_ino = 0; 837 if (!is_dentry_allowed_for_filemod(old_dentry, &src_device_id, &src_file_ino) && 838 !is_dentry_allowed_for_filemod(new_dentry, &dst_device_id, &dst_file_ino)) 839 goto out; 840 841 int zero = 0; 842 struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero); 843 if (!filemod_data) 844 goto out; 845 846 u32 pid = get_userspace_pid(); 847 struct task_struct* task = (struct task_struct*)bpf_get_current_task(); 848 849 filemod_data->meta.type = FILEMOD_EVENT; 850 filemod_data->fmod_type = FMOD_LINK; 851 filemod_data->dst_flags = 0; 852 filemod_data->src_inode = src_file_ino; 853 filemod_data->dst_inode = dst_file_ino; 854 filemod_data->src_device_id = src_device_id; 855 filemod_data->dst_device_id = dst_device_id; 856 filemod_data->src_filepath_length = 0; 857 filemod_data->dst_filepath_length = 0; 858 859 void* payload = populate_var_metadata(&filemod_data->meta, task, pid, 860 filemod_data->payload); 861 payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload); 862 863 size_t len = read_absolute_file_path_from_dentry(old_dentry, payload); 864 barrier_var(len); 865 if (len <= MAX_FILEPATH_LENGTH) { 866 barrier_var(len); 867 payload += len; 868 filemod_data->src_filepath_length = len; 869 } 870 871 len = read_absolute_file_path_from_dentry(new_dentry, payload); 872 barrier_var(len); 873 if (len <= MAX_FILEPATH_LENGTH) { 874 barrier_var(len); 875 payload += len; 876 filemod_data->dst_filepath_length = len; 877 } 878 879 bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta); 880 unsigned long data_len = payload - (void*)filemod_data; 881 data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len; 882 bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len); 883 out: 884 bpf_stats_exit(&stats_ctx); 885 return 0; 886 } 887 888 SEC("kprobe/vfs_symlink") 889 int BPF_KPROBE(kprobe__vfs_symlink, struct inode* dir, struct dentry* dentry, 890 const char* oldname) 891 { 892 struct bpf_func_stats_ctx stats_ctx; 893 bpf_stats_enter(&stats_ctx, profiler_bpf_vfs_symlink); 894 895 u32 dst_device_id = 0; 896 u64 dst_file_ino = 0; 897 if (!is_dentry_allowed_for_filemod(dentry, &dst_device_id, &dst_file_ino)) 898 goto out; 899 900 int zero = 0; 901 struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero); 902 if (!filemod_data) 903 goto out; 904 905 u32 pid = get_userspace_pid(); 906 struct task_struct* task = (struct task_struct*)bpf_get_current_task(); 907 908 filemod_data->meta.type = FILEMOD_EVENT; 909 filemod_data->fmod_type = FMOD_SYMLINK; 910 filemod_data->dst_flags = 0; 911 filemod_data->src_inode = 0; 912 filemod_data->dst_inode = dst_file_ino; 913 filemod_data->src_device_id = 0; 914 filemod_data->dst_device_id = dst_device_id; 915 filemod_data->src_filepath_length = 0; 916 filemod_data->dst_filepath_length = 0; 917 918 void* payload = populate_var_metadata(&filemod_data->meta, task, pid, 919 filemod_data->payload); 920 payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload); 921 922 size_t len = bpf_probe_read_str(payload, MAX_FILEPATH_LENGTH, oldname); 923 barrier_var(len); 924 if (len <= MAX_FILEPATH_LENGTH) { 925 barrier_var(len); 926 payload += len; 927 filemod_data->src_filepath_length = len; 928 } 929 len = read_absolute_file_path_from_dentry(dentry, payload); 930 barrier_var(len); 931 if (len <= MAX_FILEPATH_LENGTH) { 932 barrier_var(len); 933 payload += len; 934 filemod_data->dst_filepath_length = len; 935 } 936 bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta); 937 unsigned long data_len = payload - (void*)filemod_data; 938 data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len; 939 bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len); 940 out: 941 bpf_stats_exit(&stats_ctx); 942 return 0; 943 } 944 945 SEC("raw_tracepoint/sched_process_fork") 946 int raw_tracepoint__sched_process_fork(struct bpf_raw_tracepoint_args* ctx) 947 { 948 struct bpf_func_stats_ctx stats_ctx; 949 bpf_stats_enter(&stats_ctx, profiler_bpf_sched_process_fork); 950 951 int zero = 0; 952 struct var_fork_data_t* fork_data = bpf_map_lookup_elem(&data_heap, &zero); 953 if (!fork_data) 954 goto out; 955 956 struct task_struct* parent = (struct task_struct*)ctx->args[0]; 957 struct task_struct* child = (struct task_struct*)ctx->args[1]; 958 fork_data->meta.type = FORK_EVENT; 959 960 void* payload = populate_var_metadata(&fork_data->meta, child, 961 BPF_CORE_READ(child, pid), fork_data->payload); 962 fork_data->parent_pid = BPF_CORE_READ(parent, pid); 963 fork_data->parent_exec_id = BPF_CORE_READ(parent, self_exec_id); 964 fork_data->parent_start_time = BPF_CORE_READ(parent, start_time); 965 bpf_stats_pre_submit_var_perf_event(&stats_ctx, &fork_data->meta); 966 967 unsigned long data_len = payload - (void*)fork_data; 968 data_len = data_len > sizeof(*fork_data) ? sizeof(*fork_data) : data_len; 969 bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, fork_data, data_len); 970 out: 971 bpf_stats_exit(&stats_ctx); 972 return 0; 973 } 974 char _license[] SEC("license") = "GPL"; 975