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v6.13.7
  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#include "err.h"
 10#include "bpf_experimental.h"
 11#include "bpf_compiler.h"
 12#include "bpf_misc.h"
 13
 14#ifndef NULL
 15#define NULL 0
 16#endif
 17
 18#define O_WRONLY 00000001
 19#define O_RDWR 00000002
 20#define O_DIRECTORY 00200000
 21#define __O_TMPFILE 020000000
 22#define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)
 23#define S_IFMT 00170000
 24#define S_IFSOCK 0140000
 25#define S_IFLNK 0120000
 26#define S_IFREG 0100000
 27#define S_IFBLK 0060000
 28#define S_IFDIR 0040000
 29#define S_IFCHR 0020000
 30#define S_IFIFO 0010000
 31#define S_ISUID 0004000
 32#define S_ISGID 0002000
 33#define S_ISVTX 0001000
 34#define S_ISLNK(m) (((m)&S_IFMT) == S_IFLNK)
 35#define S_ISDIR(m) (((m)&S_IFMT) == S_IFDIR)
 36#define S_ISCHR(m) (((m)&S_IFMT) == S_IFCHR)
 37#define S_ISBLK(m) (((m)&S_IFMT) == S_IFBLK)
 38#define S_ISFIFO(m) (((m)&S_IFMT) == S_IFIFO)
 39#define S_ISSOCK(m) (((m)&S_IFMT) == S_IFSOCK)
 40
 41#define KILL_DATA_ARRAY_SIZE 8
 42
 43struct var_kill_data_arr_t {
 44	struct var_kill_data_t array[KILL_DATA_ARRAY_SIZE];
 45};
 46
 47union any_profiler_data_t {
 48	struct var_exec_data_t var_exec;
 49	struct var_kill_data_t var_kill;
 50	struct var_sysctl_data_t var_sysctl;
 51	struct var_filemod_data_t var_filemod;
 52	struct var_fork_data_t var_fork;
 53	struct var_kill_data_arr_t var_kill_data_arr;
 54};
 55
 56volatile struct profiler_config_struct bpf_config = {};
 57
 58#define FETCH_CGROUPS_FROM_BPF (bpf_config.fetch_cgroups_from_bpf)
 59#define CGROUP_FS_INODE (bpf_config.cgroup_fs_inode)
 60#define CGROUP_LOGIN_SESSION_INODE \
 61	(bpf_config.cgroup_login_session_inode)
 62#define KILL_SIGNALS (bpf_config.kill_signals_mask)
 63#define STALE_INFO (bpf_config.stale_info_secs)
 64#define INODE_FILTER (bpf_config.inode_filter)
 65#define READ_ENVIRON_FROM_EXEC (bpf_config.read_environ_from_exec)
 66#define ENABLE_CGROUP_V1_RESOLVER (bpf_config.enable_cgroup_v1_resolver)
 67
 68struct kernfs_iattrs___52 {
 69	struct iattr ia_iattr;
 70};
 71
 72struct kernfs_node___52 {
 73	union /* kernfs_node_id */ {
 74		struct {
 75			u32 ino;
 76			u32 generation;
 77		};
 78		u64 id;
 79	} id;
 80};
 81
 82struct {
 83	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
 84	__uint(max_entries, 1);
 85	__type(key, u32);
 86	__type(value, union any_profiler_data_t);
 87} data_heap SEC(".maps");
 88
 89struct {
 90	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
 91	__uint(key_size, sizeof(int));
 92	__uint(value_size, sizeof(int));
 93} events SEC(".maps");
 94
 95struct {
 96	__uint(type, BPF_MAP_TYPE_HASH);
 97	__uint(max_entries, KILL_DATA_ARRAY_SIZE);
 98	__type(key, u32);
 99	__type(value, struct var_kill_data_arr_t);
100} var_tpid_to_data SEC(".maps");
101
102struct {
103	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
104	__uint(max_entries, profiler_bpf_max_function_id);
105	__type(key, u32);
106	__type(value, struct bpf_func_stats_data);
107} bpf_func_stats SEC(".maps");
108
109struct {
110	__uint(type, BPF_MAP_TYPE_HASH);
111	__type(key, u32);
112	__type(value, bool);
113	__uint(max_entries, 16);
114} allowed_devices SEC(".maps");
115
116struct {
117	__uint(type, BPF_MAP_TYPE_HASH);
118	__type(key, u64);
119	__type(value, bool);
120	__uint(max_entries, 1024);
121} allowed_file_inodes SEC(".maps");
122
123struct {
124	__uint(type, BPF_MAP_TYPE_HASH);
125	__type(key, u64);
126	__type(value, bool);
127	__uint(max_entries, 1024);
128} allowed_directory_inodes SEC(".maps");
129
130struct {
131	__uint(type, BPF_MAP_TYPE_HASH);
132	__type(key, u32);
133	__type(value, bool);
134	__uint(max_entries, 16);
135} disallowed_exec_inodes SEC(".maps");
 
 
 
 
136
137static INLINE bool IS_ERR(const void* ptr)
138{
139	return IS_ERR_VALUE((unsigned long)ptr);
140}
141
142static INLINE u32 get_userspace_pid()
143{
144	return bpf_get_current_pid_tgid() >> 32;
145}
146
147static INLINE bool is_init_process(u32 tgid)
148{
149	return tgid == 1 || tgid == 0;
150}
151
152static INLINE unsigned long
153probe_read_lim(void* dst, void* src, unsigned long len, unsigned long max)
154{
155	len = len < max ? len : max;
156	if (len > 1) {
157		if (bpf_probe_read_kernel(dst, len, src))
158			return 0;
159	} else if (len == 1) {
160		if (bpf_probe_read_kernel(dst, 1, src))
161			return 0;
162	}
163	return len;
164}
165
166static INLINE int get_var_spid_index(struct var_kill_data_arr_t* arr_struct,
167				     int spid)
168{
169#ifdef UNROLL
170	__pragma_loop_unroll
171#endif
172	for (int i = 0; i < ARRAY_SIZE(arr_struct->array); i++)
173		if (arr_struct->array[i].meta.pid == spid)
174			return i;
175	return -1;
176}
177
178static INLINE void populate_ancestors(struct task_struct* task,
179				      struct ancestors_data_t* ancestors_data)
180{
181	struct task_struct* parent = task;
182	u32 num_ancestors, ppid;
183
184	ancestors_data->num_ancestors = 0;
185#ifdef UNROLL
186	__pragma_loop_unroll
187#endif
188	for (num_ancestors = 0; num_ancestors < MAX_ANCESTORS; num_ancestors++) {
189		parent = BPF_CORE_READ(parent, real_parent);
190		if (parent == NULL)
191			break;
192		ppid = BPF_CORE_READ(parent, tgid);
193		if (is_init_process(ppid))
194			break;
195		ancestors_data->ancestor_pids[num_ancestors] = ppid;
196		ancestors_data->ancestor_exec_ids[num_ancestors] =
197			BPF_CORE_READ(parent, self_exec_id);
198		ancestors_data->ancestor_start_times[num_ancestors] =
199			BPF_CORE_READ(parent, start_time);
200		ancestors_data->num_ancestors = num_ancestors;
201	}
202}
203
204static INLINE void* read_full_cgroup_path(struct kernfs_node* cgroup_node,
205					  struct kernfs_node* cgroup_root_node,
206					  void* payload,
207					  int* root_pos)
208{
209	void* payload_start = payload;
210	size_t filepart_length;
211
212#ifdef UNROLL
213	__pragma_loop_unroll
214#endif
215	for (int i = 0; i < MAX_CGROUPS_PATH_DEPTH; i++) {
216		filepart_length =
217			bpf_probe_read_kernel_str(payload, MAX_PATH,
218						  BPF_CORE_READ(cgroup_node, name));
219		if (!cgroup_node)
220			return payload;
221		if (cgroup_node == cgroup_root_node)
222			*root_pos = payload - payload_start;
223		if (bpf_cmp_likely(filepart_length, <=, MAX_PATH)) {
224			payload += filepart_length;
225		}
226		cgroup_node = BPF_CORE_READ(cgroup_node, parent);
227	}
228	return payload;
229}
230
231static ino_t get_inode_from_kernfs(struct kernfs_node* node)
232{
233	struct kernfs_node___52* node52 = (void*)node;
234
235	if (bpf_core_field_exists(node52->id.ino)) {
236		barrier_var(node52);
237		return BPF_CORE_READ(node52, id.ino);
238	} else {
239		barrier_var(node);
240		return (u64)BPF_CORE_READ(node, id);
241	}
242}
243
244extern bool CONFIG_CGROUP_PIDS __kconfig __weak;
245enum cgroup_subsys_id___local {
246	pids_cgrp_id___local = 123, /* value doesn't matter */
247};
248
249static INLINE void* populate_cgroup_info(struct cgroup_data_t* cgroup_data,
250					 struct task_struct* task,
251					 void* payload)
252{
253	struct kernfs_node* root_kernfs =
254		BPF_CORE_READ(task, nsproxy, cgroup_ns, root_cset, dfl_cgrp, kn);
255	struct kernfs_node* proc_kernfs = BPF_CORE_READ(task, cgroups, dfl_cgrp, kn);
256
257#if __has_builtin(__builtin_preserve_enum_value)
258	if (ENABLE_CGROUP_V1_RESOLVER && CONFIG_CGROUP_PIDS) {
259		int cgrp_id = bpf_core_enum_value(enum cgroup_subsys_id___local,
260						  pids_cgrp_id___local);
261#ifdef UNROLL
262		__pragma_loop_unroll
263#endif
264		for (int i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
265			struct cgroup_subsys_state* subsys =
266				BPF_CORE_READ(task, cgroups, subsys[i]);
267			if (subsys != NULL) {
268				int subsys_id = BPF_CORE_READ(subsys, ss, id);
269				if (subsys_id == cgrp_id) {
270					proc_kernfs = BPF_CORE_READ(subsys, cgroup, kn);
271					root_kernfs = BPF_CORE_READ(subsys, ss, root, kf_root, kn);
272					break;
273				}
274			}
275		}
276	}
277#endif
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_kernel_str(payload, MAX_PATH,
305					  BPF_CORE_READ(root_kernfs, name));
306	if (bpf_cmp_likely(cgroup_root_length, <=, MAX_PATH)) {
307		cgroup_data->cgroup_root_length = cgroup_root_length;
308		payload += cgroup_root_length;
309	}
310
311	size_t cgroup_proc_length =
312		bpf_probe_read_kernel_str(payload, MAX_PATH,
313					  BPF_CORE_READ(proc_kernfs, name));
314	if (bpf_cmp_likely(cgroup_proc_length, <=, MAX_PATH)) {
315		cgroup_data->cgroup_proc_length = cgroup_proc_length;
316		payload += cgroup_proc_length;
317	}
318
319	if (FETCH_CGROUPS_FROM_BPF) {
320		cgroup_data->cgroup_full_path_root_pos = -1;
321		void* payload_end_pos = read_full_cgroup_path(proc_kernfs, root_kernfs, payload,
322							      &cgroup_data->cgroup_full_path_root_pos);
323		cgroup_data->cgroup_full_length = payload_end_pos - payload;
324		payload = payload_end_pos;
325	}
326
327	return (void*)payload;
328}
329
330static INLINE void* populate_var_metadata(struct var_metadata_t* metadata,
331					  struct task_struct* task,
332					  u32 pid, void* payload)
333{
334	u64 uid_gid = bpf_get_current_uid_gid();
335
336	metadata->uid = (u32)uid_gid;
337	metadata->gid = uid_gid >> 32;
338	metadata->pid = pid;
339	metadata->exec_id = BPF_CORE_READ(task, self_exec_id);
340	metadata->start_time = BPF_CORE_READ(task, start_time);
341	metadata->comm_length = 0;
342
343	size_t comm_length = bpf_core_read_str(payload, TASK_COMM_LEN, &task->comm);
344	if (bpf_cmp_likely(comm_length, <=, TASK_COMM_LEN)) {
345		metadata->comm_length = comm_length;
346		payload += comm_length;
347	}
348
349	return (void*)payload;
350}
351
352static INLINE struct var_kill_data_t*
353get_var_kill_data(struct pt_regs* ctx, int spid, int tpid, int sig)
354{
355	int zero = 0;
356	struct var_kill_data_t* kill_data = bpf_map_lookup_elem(&data_heap, &zero);
357
358	if (kill_data == NULL)
359		return NULL;
360	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
361
362	void* payload = populate_var_metadata(&kill_data->meta, task, spid, kill_data->payload);
363	payload = populate_cgroup_info(&kill_data->cgroup_data, task, payload);
364	size_t payload_length = payload - (void*)kill_data->payload;
365	kill_data->payload_length = payload_length;
366	populate_ancestors(task, &kill_data->ancestors_info);
367	kill_data->meta.type = KILL_EVENT;
368	kill_data->kill_target_pid = tpid;
369	kill_data->kill_sig = sig;
370	kill_data->kill_count = 1;
371	kill_data->last_kill_time = bpf_ktime_get_ns();
372	return kill_data;
373}
374
375static INLINE int trace_var_sys_kill(void* ctx, int tpid, int sig)
376{
377	if ((KILL_SIGNALS & (1ULL << sig)) == 0)
378		return 0;
379
380	u32 spid = get_userspace_pid();
381	struct var_kill_data_arr_t* arr_struct = bpf_map_lookup_elem(&var_tpid_to_data, &tpid);
382
383	if (arr_struct == NULL) {
384		struct var_kill_data_t* kill_data = get_var_kill_data(ctx, spid, tpid, sig);
385		int zero = 0;
386
387		if (kill_data == NULL)
388			return 0;
389		arr_struct = bpf_map_lookup_elem(&data_heap, &zero);
390		if (arr_struct == NULL)
391			return 0;
392		bpf_probe_read_kernel(&arr_struct->array[0],
393				      sizeof(arr_struct->array[0]), kill_data);
394	} else {
395		int index = get_var_spid_index(arr_struct, spid);
396
397		if (index == -1) {
398			struct var_kill_data_t* kill_data =
399				get_var_kill_data(ctx, spid, tpid, sig);
400			if (kill_data == NULL)
401				return 0;
402#ifdef UNROLL
403			__pragma_loop_unroll
404#endif
405			for (int i = 0; i < ARRAY_SIZE(arr_struct->array); i++)
406				if (arr_struct->array[i].meta.pid == 0) {
407					bpf_probe_read_kernel(&arr_struct->array[i],
408							      sizeof(arr_struct->array[i]),
409							      kill_data);
410					bpf_map_update_elem(&var_tpid_to_data, &tpid,
411							    arr_struct, 0);
412
413					return 0;
414				}
415			return 0;
416		}
417
418		struct var_kill_data_t* kill_data = &arr_struct->array[index];
419
420		u64 delta_sec =
421			(bpf_ktime_get_ns() - kill_data->last_kill_time) / 1000000000;
422
423		if (delta_sec < STALE_INFO) {
424			kill_data->kill_count++;
425			kill_data->last_kill_time = bpf_ktime_get_ns();
426			bpf_probe_read_kernel(&arr_struct->array[index],
427					      sizeof(arr_struct->array[index]),
428					      kill_data);
429		} else {
430			struct var_kill_data_t* kill_data =
431				get_var_kill_data(ctx, spid, tpid, sig);
432			if (kill_data == NULL)
433				return 0;
434			bpf_probe_read_kernel(&arr_struct->array[index],
435					      sizeof(arr_struct->array[index]),
436					      kill_data);
437		}
438	}
439	bpf_map_update_elem(&var_tpid_to_data, &tpid, arr_struct, 0);
440	return 0;
441}
442
443static INLINE void bpf_stats_enter(struct bpf_func_stats_ctx* bpf_stat_ctx,
444				   enum bpf_function_id func_id)
445{
446	int func_id_key = func_id;
447
448	bpf_stat_ctx->start_time_ns = bpf_ktime_get_ns();
449	bpf_stat_ctx->bpf_func_stats_data_val =
450		bpf_map_lookup_elem(&bpf_func_stats, &func_id_key);
451	if (bpf_stat_ctx->bpf_func_stats_data_val)
452		bpf_stat_ctx->bpf_func_stats_data_val->num_executions++;
453}
454
455static INLINE void bpf_stats_exit(struct bpf_func_stats_ctx* bpf_stat_ctx)
456{
457	if (bpf_stat_ctx->bpf_func_stats_data_val)
458		bpf_stat_ctx->bpf_func_stats_data_val->time_elapsed_ns +=
459			bpf_ktime_get_ns() - bpf_stat_ctx->start_time_ns;
460}
461
462static INLINE void
463bpf_stats_pre_submit_var_perf_event(struct bpf_func_stats_ctx* bpf_stat_ctx,
464				    struct var_metadata_t* meta)
465{
466	if (bpf_stat_ctx->bpf_func_stats_data_val) {
467		bpf_stat_ctx->bpf_func_stats_data_val->num_perf_events++;
468		meta->bpf_stats_num_perf_events =
469			bpf_stat_ctx->bpf_func_stats_data_val->num_perf_events;
470	}
471	meta->bpf_stats_start_ktime_ns = bpf_stat_ctx->start_time_ns;
472	meta->cpu_id = bpf_get_smp_processor_id();
473}
474
475static INLINE size_t
476read_absolute_file_path_from_dentry(struct dentry* filp_dentry, void* payload)
477{
478	size_t length = 0;
479	size_t filepart_length;
480	struct dentry* parent_dentry;
481
482#ifdef UNROLL
483	__pragma_loop_unroll
484#endif
485	for (int i = 0; i < MAX_PATH_DEPTH; i++) {
486		filepart_length =
487			bpf_probe_read_kernel_str(payload, MAX_PATH,
488						  BPF_CORE_READ(filp_dentry, d_name.name));
489		bpf_nop_mov(filepart_length);
490		if (bpf_cmp_unlikely(filepart_length, >, MAX_PATH))
491			break;
492		payload += filepart_length;
493		length += filepart_length;
494
495		parent_dentry = BPF_CORE_READ(filp_dentry, d_parent);
496		if (filp_dentry == parent_dentry)
497			break;
498		filp_dentry = parent_dentry;
499	}
500
501	return length;
502}
503
504static INLINE bool
505is_ancestor_in_allowed_inodes(struct dentry* filp_dentry)
506{
507	struct dentry* parent_dentry;
508#ifdef UNROLL
509	__pragma_loop_unroll
510#endif
511	for (int i = 0; i < MAX_PATH_DEPTH; i++) {
512		u64 dir_ino = BPF_CORE_READ(filp_dentry, d_inode, i_ino);
513		bool* allowed_dir = bpf_map_lookup_elem(&allowed_directory_inodes, &dir_ino);
514
515		if (allowed_dir != NULL)
516			return true;
517		parent_dentry = BPF_CORE_READ(filp_dentry, d_parent);
518		if (filp_dentry == parent_dentry)
519			break;
520		filp_dentry = parent_dentry;
521	}
522	return false;
523}
524
525static INLINE bool is_dentry_allowed_for_filemod(struct dentry* file_dentry,
526						 u32* device_id,
527						 u64* file_ino)
528{
529	u32 dev_id = BPF_CORE_READ(file_dentry, d_sb, s_dev);
530	*device_id = dev_id;
531	bool* allowed_device = bpf_map_lookup_elem(&allowed_devices, &dev_id);
532
533	if (allowed_device == NULL)
534		return false;
535
536	u64 ino = BPF_CORE_READ(file_dentry, d_inode, i_ino);
537	*file_ino = ino;
538	bool* allowed_file = bpf_map_lookup_elem(&allowed_file_inodes, &ino);
539
540	if (allowed_file == NULL)
541		if (!is_ancestor_in_allowed_inodes(BPF_CORE_READ(file_dentry, d_parent)))
542			return false;
543	return true;
544}
545
546SEC("kprobe/proc_sys_write")
547ssize_t BPF_KPROBE(kprobe__proc_sys_write,
548		   struct file* filp, const char* buf,
549		   size_t count, loff_t* ppos)
550{
551	struct bpf_func_stats_ctx stats_ctx;
552	bpf_stats_enter(&stats_ctx, profiler_bpf_proc_sys_write);
553
554	u32 pid = get_userspace_pid();
555	int zero = 0;
556	struct var_sysctl_data_t* sysctl_data =
557		bpf_map_lookup_elem(&data_heap, &zero);
558	if (!sysctl_data)
559		goto out;
560
561	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
562	sysctl_data->meta.type = SYSCTL_EVENT;
563	void* payload = populate_var_metadata(&sysctl_data->meta, task, pid, sysctl_data->payload);
564	payload = populate_cgroup_info(&sysctl_data->cgroup_data, task, payload);
565
566	populate_ancestors(task, &sysctl_data->ancestors_info);
567
568	sysctl_data->sysctl_val_length = 0;
569	sysctl_data->sysctl_path_length = 0;
570
571	size_t sysctl_val_length = bpf_probe_read_kernel_str(payload,
572							     CTL_MAXNAME, buf);
573	if (bpf_cmp_likely(sysctl_val_length, <=, CTL_MAXNAME)) {
574		sysctl_data->sysctl_val_length = sysctl_val_length;
575		payload += sysctl_val_length;
576	}
577
578	size_t sysctl_path_length =
579		bpf_probe_read_kernel_str(payload, MAX_PATH,
580					  BPF_CORE_READ(filp, f_path.dentry,
581							d_name.name));
582	if (bpf_cmp_likely(sysctl_path_length, <=, MAX_PATH)) {
583		sysctl_data->sysctl_path_length = sysctl_path_length;
584		payload += sysctl_path_length;
585	}
586
587	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &sysctl_data->meta);
588	unsigned long data_len = payload - (void*)sysctl_data;
589	data_len = data_len > sizeof(struct var_sysctl_data_t)
590		? sizeof(struct var_sysctl_data_t)
591		: data_len;
592	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, sysctl_data, data_len);
593out:
594	bpf_stats_exit(&stats_ctx);
595	return 0;
596}
597
598SEC("tracepoint/syscalls/sys_enter_kill")
599int tracepoint__syscalls__sys_enter_kill(struct syscall_trace_enter* ctx)
600{
601	struct bpf_func_stats_ctx stats_ctx;
602
603	bpf_stats_enter(&stats_ctx, profiler_bpf_sys_enter_kill);
604	int pid = ctx->args[0];
605	int sig = ctx->args[1];
606	int ret = trace_var_sys_kill(ctx, pid, sig);
607	bpf_stats_exit(&stats_ctx);
608	return ret;
609};
610
611SEC("raw_tracepoint/sched_process_exit")
612int raw_tracepoint__sched_process_exit(void* ctx)
613{
614	int zero = 0;
615	struct bpf_func_stats_ctx stats_ctx;
616	bpf_stats_enter(&stats_ctx, profiler_bpf_sched_process_exit);
617
618	u32 tpid = get_userspace_pid();
619
620	struct var_kill_data_arr_t* arr_struct = bpf_map_lookup_elem(&var_tpid_to_data, &tpid);
621	struct var_kill_data_t* kill_data = bpf_map_lookup_elem(&data_heap, &zero);
622
623	if (arr_struct == NULL || kill_data == NULL)
624		goto out;
625
626	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
627	struct kernfs_node* proc_kernfs = BPF_CORE_READ(task, cgroups, dfl_cgrp, kn);
628
629#ifdef UNROLL
630	__pragma_loop_unroll
631#endif
632	for (int i = 0; i < ARRAY_SIZE(arr_struct->array); i++) {
633		struct var_kill_data_t* past_kill_data = &arr_struct->array[i];
634
635		if (past_kill_data != NULL && past_kill_data->kill_target_pid == (pid_t)tpid) {
636			bpf_probe_read_kernel(kill_data, sizeof(*past_kill_data),
637					      past_kill_data);
638			void* payload = kill_data->payload;
639			size_t offset = kill_data->payload_length;
640			if (offset >= MAX_METADATA_PAYLOAD_LEN + MAX_CGROUP_PAYLOAD_LEN)
641				return 0;
642			payload += offset;
643
644			kill_data->kill_target_name_length = 0;
645			kill_data->kill_target_cgroup_proc_length = 0;
646
647			size_t comm_length = bpf_core_read_str(payload, TASK_COMM_LEN, &task->comm);
648			if (bpf_cmp_likely(comm_length, <=, TASK_COMM_LEN)) {
649				kill_data->kill_target_name_length = comm_length;
650				payload += comm_length;
651			}
652
653			size_t cgroup_proc_length =
654				bpf_probe_read_kernel_str(payload,
655							  KILL_TARGET_LEN,
656							  BPF_CORE_READ(proc_kernfs, name));
657			if (bpf_cmp_likely(cgroup_proc_length, <=, KILL_TARGET_LEN)) {
658				kill_data->kill_target_cgroup_proc_length = cgroup_proc_length;
659				payload += cgroup_proc_length;
660			}
661
662			bpf_stats_pre_submit_var_perf_event(&stats_ctx, &kill_data->meta);
663			unsigned long data_len = (void*)payload - (void*)kill_data;
664			data_len = data_len > sizeof(struct var_kill_data_t)
665				? sizeof(struct var_kill_data_t)
666				: data_len;
667			bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, kill_data, data_len);
668		}
669	}
670	bpf_map_delete_elem(&var_tpid_to_data, &tpid);
671out:
672	bpf_stats_exit(&stats_ctx);
673	return 0;
674}
675
676SEC("raw_tracepoint/sched_process_exec")
677int raw_tracepoint__sched_process_exec(struct bpf_raw_tracepoint_args* ctx)
678{
679	struct bpf_func_stats_ctx stats_ctx;
680	bpf_stats_enter(&stats_ctx, profiler_bpf_sched_process_exec);
681
682	struct linux_binprm* bprm = (struct linux_binprm*)ctx->args[2];
683	u64 inode = BPF_CORE_READ(bprm, file, f_inode, i_ino);
684
685	bool* should_filter_binprm = bpf_map_lookup_elem(&disallowed_exec_inodes, &inode);
686	if (should_filter_binprm != NULL)
687		goto out;
688
689	int zero = 0;
690	struct var_exec_data_t* proc_exec_data = bpf_map_lookup_elem(&data_heap, &zero);
691	if (!proc_exec_data)
692		goto out;
693
694	if (INODE_FILTER && inode != INODE_FILTER)
695		return 0;
696
697	u32 pid = get_userspace_pid();
698	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
699
700	proc_exec_data->meta.type = EXEC_EVENT;
701	proc_exec_data->bin_path_length = 0;
702	proc_exec_data->cmdline_length = 0;
703	proc_exec_data->environment_length = 0;
704	void* payload = populate_var_metadata(&proc_exec_data->meta, task, pid,
705					      proc_exec_data->payload);
706	payload = populate_cgroup_info(&proc_exec_data->cgroup_data, task, payload);
707
708	struct task_struct* parent_task = BPF_CORE_READ(task, real_parent);
709	proc_exec_data->parent_pid = BPF_CORE_READ(parent_task, tgid);
710	proc_exec_data->parent_uid = BPF_CORE_READ(parent_task, real_cred, uid.val);
711	proc_exec_data->parent_exec_id = BPF_CORE_READ(parent_task, self_exec_id);
712	proc_exec_data->parent_start_time = BPF_CORE_READ(parent_task, start_time);
713
714	const char* filename = BPF_CORE_READ(bprm, filename);
715	size_t bin_path_length =
716		bpf_probe_read_kernel_str(payload, MAX_FILENAME_LEN, filename);
717	if (bpf_cmp_likely(bin_path_length, <=, MAX_FILENAME_LEN)) {
718		proc_exec_data->bin_path_length = bin_path_length;
719		payload += bin_path_length;
720	}
721
722	void* arg_start = (void*)BPF_CORE_READ(task, mm, arg_start);
723	void* arg_end = (void*)BPF_CORE_READ(task, mm, arg_end);
724	unsigned int cmdline_length = probe_read_lim(payload, arg_start,
725						     arg_end - arg_start, MAX_ARGS_LEN);
726
727	if (bpf_cmp_likely(cmdline_length, <=, MAX_ARGS_LEN)) {
728		proc_exec_data->cmdline_length = cmdline_length;
729		payload += cmdline_length;
730	}
731
732	if (READ_ENVIRON_FROM_EXEC) {
733		void* env_start = (void*)BPF_CORE_READ(task, mm, env_start);
734		void* env_end = (void*)BPF_CORE_READ(task, mm, env_end);
735		unsigned long env_len = probe_read_lim(payload, env_start,
736						       env_end - env_start, MAX_ENVIRON_LEN);
737		if (cmdline_length <= MAX_ENVIRON_LEN) {
738			proc_exec_data->environment_length = env_len;
739			payload += env_len;
740		}
741	}
742
743	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &proc_exec_data->meta);
744	unsigned long data_len = payload - (void*)proc_exec_data;
745	data_len = data_len > sizeof(struct var_exec_data_t)
746		? sizeof(struct var_exec_data_t)
747		: data_len;
748	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, proc_exec_data, data_len);
749out:
750	bpf_stats_exit(&stats_ctx);
751	return 0;
752}
753
754SEC("kretprobe/do_filp_open")
755int kprobe_ret__do_filp_open(struct pt_regs* ctx)
756{
757	struct bpf_func_stats_ctx stats_ctx;
758	bpf_stats_enter(&stats_ctx, profiler_bpf_do_filp_open_ret);
759
760	struct file* filp = (struct file*)PT_REGS_RC_CORE(ctx);
761
762	if (filp == NULL || IS_ERR(filp))
763		goto out;
764	unsigned int flags = BPF_CORE_READ(filp, f_flags);
765	if ((flags & (O_RDWR | O_WRONLY)) == 0)
766		goto out;
767	if ((flags & O_TMPFILE) > 0)
768		goto out;
769	struct inode* file_inode = BPF_CORE_READ(filp, f_inode);
770	umode_t mode = BPF_CORE_READ(file_inode, i_mode);
771	if (S_ISDIR(mode) || S_ISCHR(mode) || S_ISBLK(mode) || S_ISFIFO(mode) ||
772	    S_ISSOCK(mode))
773		goto out;
774
775	struct dentry* filp_dentry = BPF_CORE_READ(filp, f_path.dentry);
776	u32 device_id = 0;
777	u64 file_ino = 0;
778	if (!is_dentry_allowed_for_filemod(filp_dentry, &device_id, &file_ino))
779		goto out;
780
781	int zero = 0;
782	struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero);
783	if (!filemod_data)
784		goto out;
785
786	u32 pid = get_userspace_pid();
787	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
788
789	filemod_data->meta.type = FILEMOD_EVENT;
790	filemod_data->fmod_type = FMOD_OPEN;
791	filemod_data->dst_flags = flags;
792	filemod_data->src_inode = 0;
793	filemod_data->dst_inode = file_ino;
794	filemod_data->src_device_id = 0;
795	filemod_data->dst_device_id = device_id;
796	filemod_data->src_filepath_length = 0;
797	filemod_data->dst_filepath_length = 0;
798
799	void* payload = populate_var_metadata(&filemod_data->meta, task, pid,
800					      filemod_data->payload);
801	payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload);
802
803	size_t len = read_absolute_file_path_from_dentry(filp_dentry, payload);
804	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
805		payload += len;
806		filemod_data->dst_filepath_length = len;
807	}
808	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta);
809	unsigned long data_len = payload - (void*)filemod_data;
810	data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len;
811	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len);
812out:
813	bpf_stats_exit(&stats_ctx);
814	return 0;
815}
816
817SEC("kprobe/vfs_link")
818int BPF_KPROBE(kprobe__vfs_link,
819	       struct dentry* old_dentry, struct mnt_idmap *idmap,
820	       struct inode* dir, struct dentry* new_dentry,
821	       struct inode** delegated_inode)
822{
823	struct bpf_func_stats_ctx stats_ctx;
824	bpf_stats_enter(&stats_ctx, profiler_bpf_vfs_link);
825
826	u32 src_device_id = 0;
827	u64 src_file_ino = 0;
828	u32 dst_device_id = 0;
829	u64 dst_file_ino = 0;
830	if (!is_dentry_allowed_for_filemod(old_dentry, &src_device_id, &src_file_ino) &&
831	    !is_dentry_allowed_for_filemod(new_dentry, &dst_device_id, &dst_file_ino))
832		goto out;
833
834	int zero = 0;
835	struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero);
836	if (!filemod_data)
837		goto out;
838
839	u32 pid = get_userspace_pid();
840	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
841
842	filemod_data->meta.type = FILEMOD_EVENT;
843	filemod_data->fmod_type = FMOD_LINK;
844	filemod_data->dst_flags = 0;
845	filemod_data->src_inode = src_file_ino;
846	filemod_data->dst_inode = dst_file_ino;
847	filemod_data->src_device_id = src_device_id;
848	filemod_data->dst_device_id = dst_device_id;
849	filemod_data->src_filepath_length = 0;
850	filemod_data->dst_filepath_length = 0;
851
852	void* payload = populate_var_metadata(&filemod_data->meta, task, pid,
853					      filemod_data->payload);
854	payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload);
855
856	size_t len = read_absolute_file_path_from_dentry(old_dentry, payload);
857	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
858		payload += len;
859		filemod_data->src_filepath_length = len;
860	}
861
862	len = read_absolute_file_path_from_dentry(new_dentry, payload);
863	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
864		payload += len;
865		filemod_data->dst_filepath_length = len;
866	}
867
868	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta);
869	unsigned long data_len = payload - (void*)filemod_data;
870	data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len;
871	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len);
872out:
873	bpf_stats_exit(&stats_ctx);
874	return 0;
875}
876
877SEC("kprobe/vfs_symlink")
878int BPF_KPROBE(kprobe__vfs_symlink, struct inode* dir, struct dentry* dentry,
879	       const char* oldname)
880{
881	struct bpf_func_stats_ctx stats_ctx;
882	bpf_stats_enter(&stats_ctx, profiler_bpf_vfs_symlink);
883
884	u32 dst_device_id = 0;
885	u64 dst_file_ino = 0;
886	if (!is_dentry_allowed_for_filemod(dentry, &dst_device_id, &dst_file_ino))
887		goto out;
888
889	int zero = 0;
890	struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero);
891	if (!filemod_data)
892		goto out;
893
894	u32 pid = get_userspace_pid();
895	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
896
897	filemod_data->meta.type = FILEMOD_EVENT;
898	filemod_data->fmod_type = FMOD_SYMLINK;
899	filemod_data->dst_flags = 0;
900	filemod_data->src_inode = 0;
901	filemod_data->dst_inode = dst_file_ino;
902	filemod_data->src_device_id = 0;
903	filemod_data->dst_device_id = dst_device_id;
904	filemod_data->src_filepath_length = 0;
905	filemod_data->dst_filepath_length = 0;
906
907	void* payload = populate_var_metadata(&filemod_data->meta, task, pid,
908					      filemod_data->payload);
909	payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload);
910
911	size_t len = bpf_probe_read_kernel_str(payload, MAX_FILEPATH_LENGTH,
912					       oldname);
913	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
914		payload += len;
915		filemod_data->src_filepath_length = len;
916	}
917	len = read_absolute_file_path_from_dentry(dentry, payload);
918	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
919		payload += len;
920		filemod_data->dst_filepath_length = len;
921	}
922	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta);
923	unsigned long data_len = payload - (void*)filemod_data;
924	data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len;
925	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len);
926out:
927	bpf_stats_exit(&stats_ctx);
928	return 0;
929}
930
931SEC("raw_tracepoint/sched_process_fork")
932int raw_tracepoint__sched_process_fork(struct bpf_raw_tracepoint_args* ctx)
933{
934	struct bpf_func_stats_ctx stats_ctx;
935	bpf_stats_enter(&stats_ctx, profiler_bpf_sched_process_fork);
936
937	int zero = 0;
938	struct var_fork_data_t* fork_data = bpf_map_lookup_elem(&data_heap, &zero);
939	if (!fork_data)
940		goto out;
941
942	struct task_struct* parent = (struct task_struct*)ctx->args[0];
943	struct task_struct* child = (struct task_struct*)ctx->args[1];
944	fork_data->meta.type = FORK_EVENT;
945
946	void* payload = populate_var_metadata(&fork_data->meta, child,
947					      BPF_CORE_READ(child, pid), fork_data->payload);
948	fork_data->parent_pid = BPF_CORE_READ(parent, pid);
949	fork_data->parent_exec_id = BPF_CORE_READ(parent, self_exec_id);
950	fork_data->parent_start_time = BPF_CORE_READ(parent, start_time);
951	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &fork_data->meta);
952
953	unsigned long data_len = payload - (void*)fork_data;
954	data_len = data_len > sizeof(*fork_data) ? sizeof(*fork_data) : data_len;
955	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, fork_data, data_len);
956out:
957	bpf_stats_exit(&stats_ctx);
958	return 0;
959}
960char _license[] SEC("license") = "GPL";
v6.9.4
  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#include "err.h"
 10#include "bpf_experimental.h"
 11#include "bpf_compiler.h"
 
 12
 13#ifndef NULL
 14#define NULL 0
 15#endif
 16
 17#define O_WRONLY 00000001
 18#define O_RDWR 00000002
 19#define O_DIRECTORY 00200000
 20#define __O_TMPFILE 020000000
 21#define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)
 22#define S_IFMT 00170000
 23#define S_IFSOCK 0140000
 24#define S_IFLNK 0120000
 25#define S_IFREG 0100000
 26#define S_IFBLK 0060000
 27#define S_IFDIR 0040000
 28#define S_IFCHR 0020000
 29#define S_IFIFO 0010000
 30#define S_ISUID 0004000
 31#define S_ISGID 0002000
 32#define S_ISVTX 0001000
 33#define S_ISLNK(m) (((m)&S_IFMT) == S_IFLNK)
 34#define S_ISDIR(m) (((m)&S_IFMT) == S_IFDIR)
 35#define S_ISCHR(m) (((m)&S_IFMT) == S_IFCHR)
 36#define S_ISBLK(m) (((m)&S_IFMT) == S_IFBLK)
 37#define S_ISFIFO(m) (((m)&S_IFMT) == S_IFIFO)
 38#define S_ISSOCK(m) (((m)&S_IFMT) == S_IFSOCK)
 39
 40#define KILL_DATA_ARRAY_SIZE 8
 41
 42struct var_kill_data_arr_t {
 43	struct var_kill_data_t array[KILL_DATA_ARRAY_SIZE];
 44};
 45
 46union any_profiler_data_t {
 47	struct var_exec_data_t var_exec;
 48	struct var_kill_data_t var_kill;
 49	struct var_sysctl_data_t var_sysctl;
 50	struct var_filemod_data_t var_filemod;
 51	struct var_fork_data_t var_fork;
 52	struct var_kill_data_arr_t var_kill_data_arr;
 53};
 54
 55volatile struct profiler_config_struct bpf_config = {};
 56
 57#define FETCH_CGROUPS_FROM_BPF (bpf_config.fetch_cgroups_from_bpf)
 58#define CGROUP_FS_INODE (bpf_config.cgroup_fs_inode)
 59#define CGROUP_LOGIN_SESSION_INODE \
 60	(bpf_config.cgroup_login_session_inode)
 61#define KILL_SIGNALS (bpf_config.kill_signals_mask)
 62#define STALE_INFO (bpf_config.stale_info_secs)
 63#define INODE_FILTER (bpf_config.inode_filter)
 64#define READ_ENVIRON_FROM_EXEC (bpf_config.read_environ_from_exec)
 65#define ENABLE_CGROUP_V1_RESOLVER (bpf_config.enable_cgroup_v1_resolver)
 66
 67struct kernfs_iattrs___52 {
 68	struct iattr ia_iattr;
 69};
 70
 71struct kernfs_node___52 {
 72	union /* kernfs_node_id */ {
 73		struct {
 74			u32 ino;
 75			u32 generation;
 76		};
 77		u64 id;
 78	} id;
 79};
 80
 81struct {
 82	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
 83	__uint(max_entries, 1);
 84	__type(key, u32);
 85	__type(value, union any_profiler_data_t);
 86} data_heap SEC(".maps");
 87
 88struct {
 89	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
 90	__uint(key_size, sizeof(int));
 91	__uint(value_size, sizeof(int));
 92} events SEC(".maps");
 93
 94struct {
 95	__uint(type, BPF_MAP_TYPE_HASH);
 96	__uint(max_entries, KILL_DATA_ARRAY_SIZE);
 97	__type(key, u32);
 98	__type(value, struct var_kill_data_arr_t);
 99} var_tpid_to_data SEC(".maps");
100
101struct {
102	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
103	__uint(max_entries, profiler_bpf_max_function_id);
104	__type(key, u32);
105	__type(value, struct bpf_func_stats_data);
106} bpf_func_stats SEC(".maps");
107
108struct {
109	__uint(type, BPF_MAP_TYPE_HASH);
110	__type(key, u32);
111	__type(value, bool);
112	__uint(max_entries, 16);
113} allowed_devices SEC(".maps");
114
115struct {
116	__uint(type, BPF_MAP_TYPE_HASH);
117	__type(key, u64);
118	__type(value, bool);
119	__uint(max_entries, 1024);
120} allowed_file_inodes SEC(".maps");
121
122struct {
123	__uint(type, BPF_MAP_TYPE_HASH);
124	__type(key, u64);
125	__type(value, bool);
126	__uint(max_entries, 1024);
127} allowed_directory_inodes SEC(".maps");
128
129struct {
130	__uint(type, BPF_MAP_TYPE_HASH);
131	__type(key, u32);
132	__type(value, bool);
133	__uint(max_entries, 16);
134} disallowed_exec_inodes SEC(".maps");
135
136#ifndef ARRAY_SIZE
137#define ARRAY_SIZE(arr) (int)(sizeof(arr) / sizeof(arr[0]))
138#endif
139
140static INLINE bool IS_ERR(const void* ptr)
141{
142	return IS_ERR_VALUE((unsigned long)ptr);
143}
144
145static INLINE u32 get_userspace_pid()
146{
147	return bpf_get_current_pid_tgid() >> 32;
148}
149
150static INLINE bool is_init_process(u32 tgid)
151{
152	return tgid == 1 || tgid == 0;
153}
154
155static INLINE unsigned long
156probe_read_lim(void* dst, void* src, unsigned long len, unsigned long max)
157{
158	len = len < max ? len : max;
159	if (len > 1) {
160		if (bpf_probe_read_kernel(dst, len, src))
161			return 0;
162	} else if (len == 1) {
163		if (bpf_probe_read_kernel(dst, 1, src))
164			return 0;
165	}
166	return len;
167}
168
169static INLINE int get_var_spid_index(struct var_kill_data_arr_t* arr_struct,
170				     int spid)
171{
172#ifdef UNROLL
173	__pragma_loop_unroll
174#endif
175	for (int i = 0; i < ARRAY_SIZE(arr_struct->array); i++)
176		if (arr_struct->array[i].meta.pid == spid)
177			return i;
178	return -1;
179}
180
181static INLINE void populate_ancestors(struct task_struct* task,
182				      struct ancestors_data_t* ancestors_data)
183{
184	struct task_struct* parent = task;
185	u32 num_ancestors, ppid;
186
187	ancestors_data->num_ancestors = 0;
188#ifdef UNROLL
189	__pragma_loop_unroll
190#endif
191	for (num_ancestors = 0; num_ancestors < MAX_ANCESTORS; num_ancestors++) {
192		parent = BPF_CORE_READ(parent, real_parent);
193		if (parent == NULL)
194			break;
195		ppid = BPF_CORE_READ(parent, tgid);
196		if (is_init_process(ppid))
197			break;
198		ancestors_data->ancestor_pids[num_ancestors] = ppid;
199		ancestors_data->ancestor_exec_ids[num_ancestors] =
200			BPF_CORE_READ(parent, self_exec_id);
201		ancestors_data->ancestor_start_times[num_ancestors] =
202			BPF_CORE_READ(parent, start_time);
203		ancestors_data->num_ancestors = num_ancestors;
204	}
205}
206
207static INLINE void* read_full_cgroup_path(struct kernfs_node* cgroup_node,
208					  struct kernfs_node* cgroup_root_node,
209					  void* payload,
210					  int* root_pos)
211{
212	void* payload_start = payload;
213	size_t filepart_length;
214
215#ifdef UNROLL
216	__pragma_loop_unroll
217#endif
218	for (int i = 0; i < MAX_CGROUPS_PATH_DEPTH; i++) {
219		filepart_length =
220			bpf_probe_read_kernel_str(payload, MAX_PATH,
221						  BPF_CORE_READ(cgroup_node, name));
222		if (!cgroup_node)
223			return payload;
224		if (cgroup_node == cgroup_root_node)
225			*root_pos = payload - payload_start;
226		if (bpf_cmp_likely(filepart_length, <=, MAX_PATH)) {
227			payload += filepart_length;
228		}
229		cgroup_node = BPF_CORE_READ(cgroup_node, parent);
230	}
231	return payload;
232}
233
234static ino_t get_inode_from_kernfs(struct kernfs_node* node)
235{
236	struct kernfs_node___52* node52 = (void*)node;
237
238	if (bpf_core_field_exists(node52->id.ino)) {
239		barrier_var(node52);
240		return BPF_CORE_READ(node52, id.ino);
241	} else {
242		barrier_var(node);
243		return (u64)BPF_CORE_READ(node, id);
244	}
245}
246
247extern bool CONFIG_CGROUP_PIDS __kconfig __weak;
248enum cgroup_subsys_id___local {
249	pids_cgrp_id___local = 123, /* value doesn't matter */
250};
251
252static INLINE void* populate_cgroup_info(struct cgroup_data_t* cgroup_data,
253					 struct task_struct* task,
254					 void* payload)
255{
256	struct kernfs_node* root_kernfs =
257		BPF_CORE_READ(task, nsproxy, cgroup_ns, root_cset, dfl_cgrp, kn);
258	struct kernfs_node* proc_kernfs = BPF_CORE_READ(task, cgroups, dfl_cgrp, kn);
259
260#if __has_builtin(__builtin_preserve_enum_value)
261	if (ENABLE_CGROUP_V1_RESOLVER && CONFIG_CGROUP_PIDS) {
262		int cgrp_id = bpf_core_enum_value(enum cgroup_subsys_id___local,
263						  pids_cgrp_id___local);
264#ifdef UNROLL
265		__pragma_loop_unroll
266#endif
267		for (int i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
268			struct cgroup_subsys_state* subsys =
269				BPF_CORE_READ(task, cgroups, subsys[i]);
270			if (subsys != NULL) {
271				int subsys_id = BPF_CORE_READ(subsys, ss, id);
272				if (subsys_id == cgrp_id) {
273					proc_kernfs = BPF_CORE_READ(subsys, cgroup, kn);
274					root_kernfs = BPF_CORE_READ(subsys, ss, root, kf_root, kn);
275					break;
276				}
277			}
278		}
279	}
280#endif
281
282	cgroup_data->cgroup_root_inode = get_inode_from_kernfs(root_kernfs);
283	cgroup_data->cgroup_proc_inode = get_inode_from_kernfs(proc_kernfs);
284
285	if (bpf_core_field_exists(root_kernfs->iattr->ia_mtime)) {
286		cgroup_data->cgroup_root_mtime =
287			BPF_CORE_READ(root_kernfs, iattr, ia_mtime.tv_nsec);
288		cgroup_data->cgroup_proc_mtime =
289			BPF_CORE_READ(proc_kernfs, iattr, ia_mtime.tv_nsec);
290	} else {
291		struct kernfs_iattrs___52* root_iattr =
292			(struct kernfs_iattrs___52*)BPF_CORE_READ(root_kernfs, iattr);
293		cgroup_data->cgroup_root_mtime =
294			BPF_CORE_READ(root_iattr, ia_iattr.ia_mtime.tv_nsec);
295
296		struct kernfs_iattrs___52* proc_iattr =
297			(struct kernfs_iattrs___52*)BPF_CORE_READ(proc_kernfs, iattr);
298		cgroup_data->cgroup_proc_mtime =
299			BPF_CORE_READ(proc_iattr, ia_iattr.ia_mtime.tv_nsec);
300	}
301
302	cgroup_data->cgroup_root_length = 0;
303	cgroup_data->cgroup_proc_length = 0;
304	cgroup_data->cgroup_full_length = 0;
305
306	size_t cgroup_root_length =
307		bpf_probe_read_kernel_str(payload, MAX_PATH,
308					  BPF_CORE_READ(root_kernfs, name));
309	if (bpf_cmp_likely(cgroup_root_length, <=, MAX_PATH)) {
310		cgroup_data->cgroup_root_length = cgroup_root_length;
311		payload += cgroup_root_length;
312	}
313
314	size_t cgroup_proc_length =
315		bpf_probe_read_kernel_str(payload, MAX_PATH,
316					  BPF_CORE_READ(proc_kernfs, name));
317	if (bpf_cmp_likely(cgroup_proc_length, <=, MAX_PATH)) {
318		cgroup_data->cgroup_proc_length = cgroup_proc_length;
319		payload += cgroup_proc_length;
320	}
321
322	if (FETCH_CGROUPS_FROM_BPF) {
323		cgroup_data->cgroup_full_path_root_pos = -1;
324		void* payload_end_pos = read_full_cgroup_path(proc_kernfs, root_kernfs, payload,
325							      &cgroup_data->cgroup_full_path_root_pos);
326		cgroup_data->cgroup_full_length = payload_end_pos - payload;
327		payload = payload_end_pos;
328	}
329
330	return (void*)payload;
331}
332
333static INLINE void* populate_var_metadata(struct var_metadata_t* metadata,
334					  struct task_struct* task,
335					  u32 pid, void* payload)
336{
337	u64 uid_gid = bpf_get_current_uid_gid();
338
339	metadata->uid = (u32)uid_gid;
340	metadata->gid = uid_gid >> 32;
341	metadata->pid = pid;
342	metadata->exec_id = BPF_CORE_READ(task, self_exec_id);
343	metadata->start_time = BPF_CORE_READ(task, start_time);
344	metadata->comm_length = 0;
345
346	size_t comm_length = bpf_core_read_str(payload, TASK_COMM_LEN, &task->comm);
347	if (bpf_cmp_likely(comm_length, <=, TASK_COMM_LEN)) {
348		metadata->comm_length = comm_length;
349		payload += comm_length;
350	}
351
352	return (void*)payload;
353}
354
355static INLINE struct var_kill_data_t*
356get_var_kill_data(struct pt_regs* ctx, int spid, int tpid, int sig)
357{
358	int zero = 0;
359	struct var_kill_data_t* kill_data = bpf_map_lookup_elem(&data_heap, &zero);
360
361	if (kill_data == NULL)
362		return NULL;
363	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
364
365	void* payload = populate_var_metadata(&kill_data->meta, task, spid, kill_data->payload);
366	payload = populate_cgroup_info(&kill_data->cgroup_data, task, payload);
367	size_t payload_length = payload - (void*)kill_data->payload;
368	kill_data->payload_length = payload_length;
369	populate_ancestors(task, &kill_data->ancestors_info);
370	kill_data->meta.type = KILL_EVENT;
371	kill_data->kill_target_pid = tpid;
372	kill_data->kill_sig = sig;
373	kill_data->kill_count = 1;
374	kill_data->last_kill_time = bpf_ktime_get_ns();
375	return kill_data;
376}
377
378static INLINE int trace_var_sys_kill(void* ctx, int tpid, int sig)
379{
380	if ((KILL_SIGNALS & (1ULL << sig)) == 0)
381		return 0;
382
383	u32 spid = get_userspace_pid();
384	struct var_kill_data_arr_t* arr_struct = bpf_map_lookup_elem(&var_tpid_to_data, &tpid);
385
386	if (arr_struct == NULL) {
387		struct var_kill_data_t* kill_data = get_var_kill_data(ctx, spid, tpid, sig);
388		int zero = 0;
389
390		if (kill_data == NULL)
391			return 0;
392		arr_struct = bpf_map_lookup_elem(&data_heap, &zero);
393		if (arr_struct == NULL)
394			return 0;
395		bpf_probe_read_kernel(&arr_struct->array[0],
396				      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_loop_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_kernel(&arr_struct->array[i],
411							      sizeof(arr_struct->array[i]),
412							      kill_data);
413					bpf_map_update_elem(&var_tpid_to_data, &tpid,
414							    arr_struct, 0);
415
416					return 0;
417				}
418			return 0;
419		}
420
421		struct var_kill_data_t* kill_data = &arr_struct->array[index];
422
423		u64 delta_sec =
424			(bpf_ktime_get_ns() - kill_data->last_kill_time) / 1000000000;
425
426		if (delta_sec < STALE_INFO) {
427			kill_data->kill_count++;
428			kill_data->last_kill_time = bpf_ktime_get_ns();
429			bpf_probe_read_kernel(&arr_struct->array[index],
430					      sizeof(arr_struct->array[index]),
431					      kill_data);
432		} else {
433			struct var_kill_data_t* kill_data =
434				get_var_kill_data(ctx, spid, tpid, sig);
435			if (kill_data == NULL)
436				return 0;
437			bpf_probe_read_kernel(&arr_struct->array[index],
438					      sizeof(arr_struct->array[index]),
439					      kill_data);
440		}
441	}
442	bpf_map_update_elem(&var_tpid_to_data, &tpid, arr_struct, 0);
443	return 0;
444}
445
446static INLINE void bpf_stats_enter(struct bpf_func_stats_ctx* bpf_stat_ctx,
447				   enum bpf_function_id func_id)
448{
449	int func_id_key = func_id;
450
451	bpf_stat_ctx->start_time_ns = bpf_ktime_get_ns();
452	bpf_stat_ctx->bpf_func_stats_data_val =
453		bpf_map_lookup_elem(&bpf_func_stats, &func_id_key);
454	if (bpf_stat_ctx->bpf_func_stats_data_val)
455		bpf_stat_ctx->bpf_func_stats_data_val->num_executions++;
456}
457
458static INLINE void bpf_stats_exit(struct bpf_func_stats_ctx* bpf_stat_ctx)
459{
460	if (bpf_stat_ctx->bpf_func_stats_data_val)
461		bpf_stat_ctx->bpf_func_stats_data_val->time_elapsed_ns +=
462			bpf_ktime_get_ns() - bpf_stat_ctx->start_time_ns;
463}
464
465static INLINE void
466bpf_stats_pre_submit_var_perf_event(struct bpf_func_stats_ctx* bpf_stat_ctx,
467				    struct var_metadata_t* meta)
468{
469	if (bpf_stat_ctx->bpf_func_stats_data_val) {
470		bpf_stat_ctx->bpf_func_stats_data_val->num_perf_events++;
471		meta->bpf_stats_num_perf_events =
472			bpf_stat_ctx->bpf_func_stats_data_val->num_perf_events;
473	}
474	meta->bpf_stats_start_ktime_ns = bpf_stat_ctx->start_time_ns;
475	meta->cpu_id = bpf_get_smp_processor_id();
476}
477
478static INLINE size_t
479read_absolute_file_path_from_dentry(struct dentry* filp_dentry, void* payload)
480{
481	size_t length = 0;
482	size_t filepart_length;
483	struct dentry* parent_dentry;
484
485#ifdef UNROLL
486	__pragma_loop_unroll
487#endif
488	for (int i = 0; i < MAX_PATH_DEPTH; i++) {
489		filepart_length =
490			bpf_probe_read_kernel_str(payload, MAX_PATH,
491						  BPF_CORE_READ(filp_dentry, d_name.name));
492		bpf_nop_mov(filepart_length);
493		if (bpf_cmp_unlikely(filepart_length, >, MAX_PATH))
494			break;
495		payload += filepart_length;
496		length += filepart_length;
497
498		parent_dentry = BPF_CORE_READ(filp_dentry, d_parent);
499		if (filp_dentry == parent_dentry)
500			break;
501		filp_dentry = parent_dentry;
502	}
503
504	return length;
505}
506
507static INLINE bool
508is_ancestor_in_allowed_inodes(struct dentry* filp_dentry)
509{
510	struct dentry* parent_dentry;
511#ifdef UNROLL
512	__pragma_loop_unroll
513#endif
514	for (int i = 0; i < MAX_PATH_DEPTH; i++) {
515		u64 dir_ino = BPF_CORE_READ(filp_dentry, d_inode, i_ino);
516		bool* allowed_dir = bpf_map_lookup_elem(&allowed_directory_inodes, &dir_ino);
517
518		if (allowed_dir != NULL)
519			return true;
520		parent_dentry = BPF_CORE_READ(filp_dentry, d_parent);
521		if (filp_dentry == parent_dentry)
522			break;
523		filp_dentry = parent_dentry;
524	}
525	return false;
526}
527
528static INLINE bool is_dentry_allowed_for_filemod(struct dentry* file_dentry,
529						 u32* device_id,
530						 u64* file_ino)
531{
532	u32 dev_id = BPF_CORE_READ(file_dentry, d_sb, s_dev);
533	*device_id = dev_id;
534	bool* allowed_device = bpf_map_lookup_elem(&allowed_devices, &dev_id);
535
536	if (allowed_device == NULL)
537		return false;
538
539	u64 ino = BPF_CORE_READ(file_dentry, d_inode, i_ino);
540	*file_ino = ino;
541	bool* allowed_file = bpf_map_lookup_elem(&allowed_file_inodes, &ino);
542
543	if (allowed_file == NULL)
544		if (!is_ancestor_in_allowed_inodes(BPF_CORE_READ(file_dentry, d_parent)))
545			return false;
546	return true;
547}
548
549SEC("kprobe/proc_sys_write")
550ssize_t BPF_KPROBE(kprobe__proc_sys_write,
551		   struct file* filp, const char* buf,
552		   size_t count, loff_t* ppos)
553{
554	struct bpf_func_stats_ctx stats_ctx;
555	bpf_stats_enter(&stats_ctx, profiler_bpf_proc_sys_write);
556
557	u32 pid = get_userspace_pid();
558	int zero = 0;
559	struct var_sysctl_data_t* sysctl_data =
560		bpf_map_lookup_elem(&data_heap, &zero);
561	if (!sysctl_data)
562		goto out;
563
564	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
565	sysctl_data->meta.type = SYSCTL_EVENT;
566	void* payload = populate_var_metadata(&sysctl_data->meta, task, pid, sysctl_data->payload);
567	payload = populate_cgroup_info(&sysctl_data->cgroup_data, task, payload);
568
569	populate_ancestors(task, &sysctl_data->ancestors_info);
570
571	sysctl_data->sysctl_val_length = 0;
572	sysctl_data->sysctl_path_length = 0;
573
574	size_t sysctl_val_length = bpf_probe_read_kernel_str(payload,
575							     CTL_MAXNAME, buf);
576	if (bpf_cmp_likely(sysctl_val_length, <=, CTL_MAXNAME)) {
577		sysctl_data->sysctl_val_length = sysctl_val_length;
578		payload += sysctl_val_length;
579	}
580
581	size_t sysctl_path_length =
582		bpf_probe_read_kernel_str(payload, MAX_PATH,
583					  BPF_CORE_READ(filp, f_path.dentry,
584							d_name.name));
585	if (bpf_cmp_likely(sysctl_path_length, <=, MAX_PATH)) {
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);
596out:
597	bpf_stats_exit(&stats_ctx);
598	return 0;
599}
600
601SEC("tracepoint/syscalls/sys_enter_kill")
602int tracepoint__syscalls__sys_enter_kill(struct syscall_trace_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
614SEC("raw_tracepoint/sched_process_exit")
615int 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_loop_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 == (pid_t)tpid) {
639			bpf_probe_read_kernel(kill_data, sizeof(*past_kill_data),
640					      past_kill_data);
641			void* payload = kill_data->payload;
642			size_t offset = kill_data->payload_length;
643			if (offset >= MAX_METADATA_PAYLOAD_LEN + MAX_CGROUP_PAYLOAD_LEN)
644				return 0;
645			payload += offset;
646
647			kill_data->kill_target_name_length = 0;
648			kill_data->kill_target_cgroup_proc_length = 0;
649
650			size_t comm_length = bpf_core_read_str(payload, TASK_COMM_LEN, &task->comm);
651			if (bpf_cmp_likely(comm_length, <=, TASK_COMM_LEN)) {
652				kill_data->kill_target_name_length = comm_length;
653				payload += comm_length;
654			}
655
656			size_t cgroup_proc_length =
657				bpf_probe_read_kernel_str(payload,
658							  KILL_TARGET_LEN,
659							  BPF_CORE_READ(proc_kernfs, name));
660			if (bpf_cmp_likely(cgroup_proc_length, <=, KILL_TARGET_LEN)) {
661				kill_data->kill_target_cgroup_proc_length = cgroup_proc_length;
662				payload += cgroup_proc_length;
663			}
664
665			bpf_stats_pre_submit_var_perf_event(&stats_ctx, &kill_data->meta);
666			unsigned long data_len = (void*)payload - (void*)kill_data;
667			data_len = data_len > sizeof(struct var_kill_data_t)
668				? sizeof(struct var_kill_data_t)
669				: data_len;
670			bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, kill_data, data_len);
671		}
672	}
673	bpf_map_delete_elem(&var_tpid_to_data, &tpid);
674out:
675	bpf_stats_exit(&stats_ctx);
676	return 0;
677}
678
679SEC("raw_tracepoint/sched_process_exec")
680int raw_tracepoint__sched_process_exec(struct bpf_raw_tracepoint_args* ctx)
681{
682	struct bpf_func_stats_ctx stats_ctx;
683	bpf_stats_enter(&stats_ctx, profiler_bpf_sched_process_exec);
684
685	struct linux_binprm* bprm = (struct linux_binprm*)ctx->args[2];
686	u64 inode = BPF_CORE_READ(bprm, file, f_inode, i_ino);
687
688	bool* should_filter_binprm = bpf_map_lookup_elem(&disallowed_exec_inodes, &inode);
689	if (should_filter_binprm != NULL)
690		goto out;
691
692	int zero = 0;
693	struct var_exec_data_t* proc_exec_data = bpf_map_lookup_elem(&data_heap, &zero);
694	if (!proc_exec_data)
695		goto out;
696
697	if (INODE_FILTER && inode != INODE_FILTER)
698		return 0;
699
700	u32 pid = get_userspace_pid();
701	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
702
703	proc_exec_data->meta.type = EXEC_EVENT;
704	proc_exec_data->bin_path_length = 0;
705	proc_exec_data->cmdline_length = 0;
706	proc_exec_data->environment_length = 0;
707	void* payload = populate_var_metadata(&proc_exec_data->meta, task, pid,
708					      proc_exec_data->payload);
709	payload = populate_cgroup_info(&proc_exec_data->cgroup_data, task, payload);
710
711	struct task_struct* parent_task = BPF_CORE_READ(task, real_parent);
712	proc_exec_data->parent_pid = BPF_CORE_READ(parent_task, tgid);
713	proc_exec_data->parent_uid = BPF_CORE_READ(parent_task, real_cred, uid.val);
714	proc_exec_data->parent_exec_id = BPF_CORE_READ(parent_task, self_exec_id);
715	proc_exec_data->parent_start_time = BPF_CORE_READ(parent_task, start_time);
716
717	const char* filename = BPF_CORE_READ(bprm, filename);
718	size_t bin_path_length =
719		bpf_probe_read_kernel_str(payload, MAX_FILENAME_LEN, filename);
720	if (bpf_cmp_likely(bin_path_length, <=, MAX_FILENAME_LEN)) {
721		proc_exec_data->bin_path_length = bin_path_length;
722		payload += bin_path_length;
723	}
724
725	void* arg_start = (void*)BPF_CORE_READ(task, mm, arg_start);
726	void* arg_end = (void*)BPF_CORE_READ(task, mm, arg_end);
727	unsigned int cmdline_length = probe_read_lim(payload, arg_start,
728						     arg_end - arg_start, MAX_ARGS_LEN);
729
730	if (bpf_cmp_likely(cmdline_length, <=, MAX_ARGS_LEN)) {
731		proc_exec_data->cmdline_length = cmdline_length;
732		payload += cmdline_length;
733	}
734
735	if (READ_ENVIRON_FROM_EXEC) {
736		void* env_start = (void*)BPF_CORE_READ(task, mm, env_start);
737		void* env_end = (void*)BPF_CORE_READ(task, mm, env_end);
738		unsigned long env_len = probe_read_lim(payload, env_start,
739						       env_end - env_start, MAX_ENVIRON_LEN);
740		if (cmdline_length <= MAX_ENVIRON_LEN) {
741			proc_exec_data->environment_length = env_len;
742			payload += env_len;
743		}
744	}
745
746	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &proc_exec_data->meta);
747	unsigned long data_len = payload - (void*)proc_exec_data;
748	data_len = data_len > sizeof(struct var_exec_data_t)
749		? sizeof(struct var_exec_data_t)
750		: data_len;
751	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, proc_exec_data, data_len);
752out:
753	bpf_stats_exit(&stats_ctx);
754	return 0;
755}
756
757SEC("kretprobe/do_filp_open")
758int kprobe_ret__do_filp_open(struct pt_regs* ctx)
759{
760	struct bpf_func_stats_ctx stats_ctx;
761	bpf_stats_enter(&stats_ctx, profiler_bpf_do_filp_open_ret);
762
763	struct file* filp = (struct file*)PT_REGS_RC_CORE(ctx);
764
765	if (filp == NULL || IS_ERR(filp))
766		goto out;
767	unsigned int flags = BPF_CORE_READ(filp, f_flags);
768	if ((flags & (O_RDWR | O_WRONLY)) == 0)
769		goto out;
770	if ((flags & O_TMPFILE) > 0)
771		goto out;
772	struct inode* file_inode = BPF_CORE_READ(filp, f_inode);
773	umode_t mode = BPF_CORE_READ(file_inode, i_mode);
774	if (S_ISDIR(mode) || S_ISCHR(mode) || S_ISBLK(mode) || S_ISFIFO(mode) ||
775	    S_ISSOCK(mode))
776		goto out;
777
778	struct dentry* filp_dentry = BPF_CORE_READ(filp, f_path.dentry);
779	u32 device_id = 0;
780	u64 file_ino = 0;
781	if (!is_dentry_allowed_for_filemod(filp_dentry, &device_id, &file_ino))
782		goto out;
783
784	int zero = 0;
785	struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero);
786	if (!filemod_data)
787		goto out;
788
789	u32 pid = get_userspace_pid();
790	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
791
792	filemod_data->meta.type = FILEMOD_EVENT;
793	filemod_data->fmod_type = FMOD_OPEN;
794	filemod_data->dst_flags = flags;
795	filemod_data->src_inode = 0;
796	filemod_data->dst_inode = file_ino;
797	filemod_data->src_device_id = 0;
798	filemod_data->dst_device_id = device_id;
799	filemod_data->src_filepath_length = 0;
800	filemod_data->dst_filepath_length = 0;
801
802	void* payload = populate_var_metadata(&filemod_data->meta, task, pid,
803					      filemod_data->payload);
804	payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload);
805
806	size_t len = read_absolute_file_path_from_dentry(filp_dentry, payload);
807	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
808		payload += len;
809		filemod_data->dst_filepath_length = len;
810	}
811	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta);
812	unsigned long data_len = payload - (void*)filemod_data;
813	data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len;
814	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len);
815out:
816	bpf_stats_exit(&stats_ctx);
817	return 0;
818}
819
820SEC("kprobe/vfs_link")
821int BPF_KPROBE(kprobe__vfs_link,
822	       struct dentry* old_dentry, struct mnt_idmap *idmap,
823	       struct inode* dir, struct dentry* new_dentry,
824	       struct inode** delegated_inode)
825{
826	struct bpf_func_stats_ctx stats_ctx;
827	bpf_stats_enter(&stats_ctx, profiler_bpf_vfs_link);
828
829	u32 src_device_id = 0;
830	u64 src_file_ino = 0;
831	u32 dst_device_id = 0;
832	u64 dst_file_ino = 0;
833	if (!is_dentry_allowed_for_filemod(old_dentry, &src_device_id, &src_file_ino) &&
834	    !is_dentry_allowed_for_filemod(new_dentry, &dst_device_id, &dst_file_ino))
835		goto out;
836
837	int zero = 0;
838	struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero);
839	if (!filemod_data)
840		goto out;
841
842	u32 pid = get_userspace_pid();
843	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
844
845	filemod_data->meta.type = FILEMOD_EVENT;
846	filemod_data->fmod_type = FMOD_LINK;
847	filemod_data->dst_flags = 0;
848	filemod_data->src_inode = src_file_ino;
849	filemod_data->dst_inode = dst_file_ino;
850	filemod_data->src_device_id = src_device_id;
851	filemod_data->dst_device_id = dst_device_id;
852	filemod_data->src_filepath_length = 0;
853	filemod_data->dst_filepath_length = 0;
854
855	void* payload = populate_var_metadata(&filemod_data->meta, task, pid,
856					      filemod_data->payload);
857	payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload);
858
859	size_t len = read_absolute_file_path_from_dentry(old_dentry, payload);
860	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
861		payload += len;
862		filemod_data->src_filepath_length = len;
863	}
864
865	len = read_absolute_file_path_from_dentry(new_dentry, payload);
866	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
867		payload += len;
868		filemod_data->dst_filepath_length = len;
869	}
870
871	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta);
872	unsigned long data_len = payload - (void*)filemod_data;
873	data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len;
874	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len);
875out:
876	bpf_stats_exit(&stats_ctx);
877	return 0;
878}
879
880SEC("kprobe/vfs_symlink")
881int BPF_KPROBE(kprobe__vfs_symlink, struct inode* dir, struct dentry* dentry,
882	       const char* oldname)
883{
884	struct bpf_func_stats_ctx stats_ctx;
885	bpf_stats_enter(&stats_ctx, profiler_bpf_vfs_symlink);
886
887	u32 dst_device_id = 0;
888	u64 dst_file_ino = 0;
889	if (!is_dentry_allowed_for_filemod(dentry, &dst_device_id, &dst_file_ino))
890		goto out;
891
892	int zero = 0;
893	struct var_filemod_data_t* filemod_data = bpf_map_lookup_elem(&data_heap, &zero);
894	if (!filemod_data)
895		goto out;
896
897	u32 pid = get_userspace_pid();
898	struct task_struct* task = (struct task_struct*)bpf_get_current_task();
899
900	filemod_data->meta.type = FILEMOD_EVENT;
901	filemod_data->fmod_type = FMOD_SYMLINK;
902	filemod_data->dst_flags = 0;
903	filemod_data->src_inode = 0;
904	filemod_data->dst_inode = dst_file_ino;
905	filemod_data->src_device_id = 0;
906	filemod_data->dst_device_id = dst_device_id;
907	filemod_data->src_filepath_length = 0;
908	filemod_data->dst_filepath_length = 0;
909
910	void* payload = populate_var_metadata(&filemod_data->meta, task, pid,
911					      filemod_data->payload);
912	payload = populate_cgroup_info(&filemod_data->cgroup_data, task, payload);
913
914	size_t len = bpf_probe_read_kernel_str(payload, MAX_FILEPATH_LENGTH,
915					       oldname);
916	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
917		payload += len;
918		filemod_data->src_filepath_length = len;
919	}
920	len = read_absolute_file_path_from_dentry(dentry, payload);
921	if (bpf_cmp_likely(len, <=, MAX_FILEPATH_LENGTH)) {
922		payload += len;
923		filemod_data->dst_filepath_length = len;
924	}
925	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &filemod_data->meta);
926	unsigned long data_len = payload - (void*)filemod_data;
927	data_len = data_len > sizeof(*filemod_data) ? sizeof(*filemod_data) : data_len;
928	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, filemod_data, data_len);
929out:
930	bpf_stats_exit(&stats_ctx);
931	return 0;
932}
933
934SEC("raw_tracepoint/sched_process_fork")
935int raw_tracepoint__sched_process_fork(struct bpf_raw_tracepoint_args* ctx)
936{
937	struct bpf_func_stats_ctx stats_ctx;
938	bpf_stats_enter(&stats_ctx, profiler_bpf_sched_process_fork);
939
940	int zero = 0;
941	struct var_fork_data_t* fork_data = bpf_map_lookup_elem(&data_heap, &zero);
942	if (!fork_data)
943		goto out;
944
945	struct task_struct* parent = (struct task_struct*)ctx->args[0];
946	struct task_struct* child = (struct task_struct*)ctx->args[1];
947	fork_data->meta.type = FORK_EVENT;
948
949	void* payload = populate_var_metadata(&fork_data->meta, child,
950					      BPF_CORE_READ(child, pid), fork_data->payload);
951	fork_data->parent_pid = BPF_CORE_READ(parent, pid);
952	fork_data->parent_exec_id = BPF_CORE_READ(parent, self_exec_id);
953	fork_data->parent_start_time = BPF_CORE_READ(parent, start_time);
954	bpf_stats_pre_submit_var_perf_event(&stats_ctx, &fork_data->meta);
955
956	unsigned long data_len = payload - (void*)fork_data;
957	data_len = data_len > sizeof(*fork_data) ? sizeof(*fork_data) : data_len;
958	bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, fork_data, data_len);
959out:
960	bpf_stats_exit(&stats_ctx);
961	return 0;
962}
963char _license[] SEC("license") = "GPL";