1 // SPDX-License-Identifier: GPL-2.0
2 #include <trace/syscall.h>
3 #include <trace/events/syscalls.h>
14 #include "trace.h"
16 static DEFINE_MUTEX(syscall_trace_lock);
18 static int syscall_enter_register(struct trace_event_call *event,
20 static int syscall_exit_register(struct trace_event_call *event,
23 static struct list_head *
26 	struct syscall_metadata *entry = call->data;  in syscall_get_enter_fields()
28 	return &entry->enter_fields;  in syscall_get_enter_fields()
34 static DEFINE_XARRAY(syscalls_metadata_sparse);
35 static struct syscall_metadata **syscalls_metadata;
38 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)  in arch_syscall_match_sym_name()
66 static int
70 		return -1;  in trace_get_syscall_nr()
75 static inline int
82 static __init struct syscall_metadata *
98 		if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name))  in find_syscall_meta()
104 static struct syscall_metadata *syscall_nr_to_meta(int nr)  in syscall_nr_to_meta()
123 	return entry->name;  in get_syscall_name()
126 static enum print_line_t
130 	struct trace_array *tr = iter->tr;  in print_syscall_enter()
131 	struct trace_seq *s = &iter->seq;  in print_syscall_enter()
132 	struct trace_entry *ent = iter->ent;  in print_syscall_enter()
133 	struct syscall_trace_enter *trace;  in print_syscall_enter()  local
137 	trace = (typeof(trace))ent;  in print_syscall_enter()
138 	syscall = trace->nr;  in print_syscall_enter()
144 	if (entry->enter_event->event.type != ent->type) {  in print_syscall_enter()
149 	trace_seq_printf(s, "%s(", entry->name);  in print_syscall_enter()
151 	for (i = 0; i < entry->nb_args; i++) {  in print_syscall_enter()
157 		if (tr && tr->trace_flags & TRACE_ITER_VERBOSE)  in print_syscall_enter()
158 			trace_seq_printf(s, "%s ", entry->types[i]);  in print_syscall_enter()
161 		trace_seq_printf(s, "%s: %lx%s", entry->args[i],  in print_syscall_enter()
162 				 trace->args[i],  in print_syscall_enter()
163 				 i == entry->nb_args - 1 ? "" : ", ");  in print_syscall_enter()
173 static enum print_line_t
177 	struct trace_seq *s = &iter->seq;  in print_syscall_exit()
178 	struct trace_entry *ent = iter->ent;  in print_syscall_exit()
179 	struct syscall_trace_exit *trace;  in print_syscall_exit()  local
183 	trace = (typeof(trace))ent;  in print_syscall_exit()
184 	syscall = trace->nr;  in print_syscall_exit()
192 	if (entry->exit_event->event.type != ent->type) {  in print_syscall_exit()
197 	trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,  in print_syscall_exit()
198 				trace->ret);  in print_syscall_exit()
209 static int __init
216 #define LEN_OR_ZERO (len ? len - pos : 0)  in __set_enter_print_fmt()
219 	for (i = 0; i < entry->nb_args; i++) {  in __set_enter_print_fmt()
221 				entry->args[i], sizeof(unsigned long),  in __set_enter_print_fmt()
222 				i == entry->nb_args - 1 ? "" : ", ");  in __set_enter_print_fmt()
226 	for (i = 0; i < entry->nb_args; i++) {  in __set_enter_print_fmt()
228 				", ((unsigned long)(REC->%s))", entry->args[i]);  in __set_enter_print_fmt()
237 static int __init set_syscall_print_fmt(struct trace_event_call *call)  in set_syscall_print_fmt()
241 	struct syscall_metadata *entry = call->data;  in set_syscall_print_fmt()
243 	if (entry->enter_event != call) {  in set_syscall_print_fmt()
244 		call->print_fmt = "\"0x%lx\", REC->ret";  in set_syscall_print_fmt()
253 		return -ENOMEM;  in set_syscall_print_fmt()
257 	call->print_fmt = print_fmt;  in set_syscall_print_fmt()
262 static void __init free_syscall_print_fmt(struct trace_event_call *call)  in free_syscall_print_fmt()
264 	struct syscall_metadata *entry = call->data;  in free_syscall_print_fmt()
266 	if (entry->enter_event == call)  in free_syscall_print_fmt()
267 		kfree(call->print_fmt);  in free_syscall_print_fmt()
270 static int __init syscall_enter_define_fields(struct trace_event_call *call)  in syscall_enter_define_fields()
272 	struct syscall_trace_enter trace;  in syscall_enter_define_fields()  local
273 	struct syscall_metadata *meta = call->data;  in syscall_enter_define_fields()
274 	int offset = offsetof(typeof(trace), args);  in syscall_enter_define_fields()
278 	for (i = 0; i < meta->nb_args; i++) {  in syscall_enter_define_fields()
279 		ret = trace_define_field(call, meta->types[i],  in syscall_enter_define_fields()
280 					 meta->args[i], offset,  in syscall_enter_define_fields()
291 static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)  in ftrace_syscall_enter()  argument
304 	 * buffer and per-cpu data require preemption to be disabled.  in ftrace_syscall_enter()
314 	trace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]);  in ftrace_syscall_enter()
325 	size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;  in ftrace_syscall_enter()
332 	entry->nr = syscall_nr;  in ftrace_syscall_enter()
334 	memcpy(entry->args, args, sizeof(unsigned long) * sys_data->nb_args);  in ftrace_syscall_enter()
339 static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)  in ftrace_syscall_exit()
350 	 * buffer and per-cpu data require preemption to be disabled.  in ftrace_syscall_exit()
360 	trace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]);  in ftrace_syscall_exit()
376 	entry->nr = syscall_nr;  in ftrace_syscall_exit()
377 	entry->ret = syscall_get_return_value(current, regs);  in ftrace_syscall_exit()
382 static int reg_event_syscall_enter(struct trace_event_file *file,  in reg_event_syscall_enter()
385 	struct trace_array *tr = file->tr;  in reg_event_syscall_enter()
389 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in reg_event_syscall_enter()
391 		return -ENOSYS;  in reg_event_syscall_enter()
393 	if (!tr->sys_refcount_enter)  in reg_event_syscall_enter()
396 		rcu_assign_pointer(tr->enter_syscall_files[num], file);  in reg_event_syscall_enter()
397 		tr->sys_refcount_enter++;  in reg_event_syscall_enter()
403 static void unreg_event_syscall_enter(struct trace_event_file *file,  in unreg_event_syscall_enter()
406 	struct trace_array *tr = file->tr;  in unreg_event_syscall_enter()
409 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in unreg_event_syscall_enter()
413 	tr->sys_refcount_enter--;  in unreg_event_syscall_enter()
414 	RCU_INIT_POINTER(tr->enter_syscall_files[num], NULL);  in unreg_event_syscall_enter()
415 	if (!tr->sys_refcount_enter)  in unreg_event_syscall_enter()
420 static int reg_event_syscall_exit(struct trace_event_file *file,  in reg_event_syscall_exit()
423 	struct trace_array *tr = file->tr;  in reg_event_syscall_exit()
427 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in reg_event_syscall_exit()
429 		return -ENOSYS;  in reg_event_syscall_exit()
431 	if (!tr->sys_refcount_exit)  in reg_event_syscall_exit()
434 		rcu_assign_pointer(tr->exit_syscall_files[num], file);  in reg_event_syscall_exit()
435 		tr->sys_refcount_exit++;  in reg_event_syscall_exit()
441 static void unreg_event_syscall_exit(struct trace_event_file *file,  in unreg_event_syscall_exit()
444 	struct trace_array *tr = file->tr;  in unreg_event_syscall_exit()
447 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in unreg_event_syscall_exit()
451 	tr->sys_refcount_exit--;  in unreg_event_syscall_exit()
452 	RCU_INIT_POINTER(tr->exit_syscall_files[num], NULL);  in unreg_event_syscall_exit()
453 	if (!tr->sys_refcount_exit)  in unreg_event_syscall_exit()
458 static int __init init_syscall_trace(struct trace_event_call *call)  in init_syscall_trace()
460 	int id;  in init_syscall_trace()  local
463 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in init_syscall_trace()
466 				((struct syscall_metadata *)call->data)->name);  in init_syscall_trace()
467 		return -ENOSYS;  in init_syscall_trace()
471 		return -ENOMEM;  in init_syscall_trace()
473 	id = trace_event_raw_init(call);  in init_syscall_trace()
475 	if (id < 0) {  in init_syscall_trace()
477 		return id;  in init_syscall_trace()
480 	return id;  in init_syscall_trace()
483 static struct trace_event_fields __refdata syscall_enter_fields_array[] = {
491 	.trace		= print_syscall_enter,
495 	.trace		= print_syscall_exit,
546 		meta->syscall_nr = i;  in init_ftrace_syscalls()
562 static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls);
563 static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls);
564 static int sys_perf_refcount_enter;
565 static int sys_perf_refcount_exit;
567 static int perf_call_bpf_enter(struct trace_event_call *call, struct pt_regs *regs,  in perf_call_bpf_enter()
583 	param.syscall_nr = rec->nr;  in perf_call_bpf_enter()
584 	for (i = 0; i < sys_data->nb_args; i++)  in perf_call_bpf_enter()
585 		param.args[i] = rec->args[i];  in perf_call_bpf_enter()
589 static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)  in perf_syscall_enter()  argument
603 	 * buffer and per-cpu data require preemption to be disabled.  in perf_syscall_enter()
618 	head = this_cpu_ptr(sys_data->enter_event->perf_events);  in perf_syscall_enter()
619 	valid_prog_array = bpf_prog_array_valid(sys_data->enter_event);  in perf_syscall_enter()
624 	size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);  in perf_syscall_enter()
626 	size -= sizeof(u32);  in perf_syscall_enter()
632 	rec->nr = syscall_nr;  in perf_syscall_enter()
634 	memcpy(&rec->args, args, sizeof(unsigned long) * sys_data->nb_args);  in perf_syscall_enter()
637 	     !perf_call_bpf_enter(sys_data->enter_event, fake_regs, sys_data, rec)) ||  in perf_syscall_enter()
644 			      sys_data->enter_event->event.type, 1, regs,  in perf_syscall_enter()
648 static int perf_sysenter_enable(struct trace_event_call *call)  in perf_sysenter_enable()
653 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in perf_sysenter_enable()
659 		pr_info("event trace: Could not activate syscall entry trace point");  in perf_sysenter_enable()
668 static void perf_sysenter_disable(struct trace_event_call *call)  in perf_sysenter_disable()
672 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in perf_sysenter_disable()
675 	sys_perf_refcount_enter--;  in perf_sysenter_disable()
682 static int perf_call_bpf_exit(struct trace_event_call *call, struct pt_regs *regs,  in perf_call_bpf_exit()
694 	param.syscall_nr = rec->nr;  in perf_call_bpf_exit()
695 	param.ret = rec->ret;  in perf_call_bpf_exit()
699 static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)  in perf_syscall_exit()
712 	 * buffer and per-cpu data require preemption to be disabled.  in perf_syscall_exit()
727 	head = this_cpu_ptr(sys_data->exit_event->perf_events);  in perf_syscall_exit()
728 	valid_prog_array = bpf_prog_array_valid(sys_data->exit_event);  in perf_syscall_exit()
734 	size -= sizeof(u32);  in perf_syscall_exit()
740 	rec->nr = syscall_nr;  in perf_syscall_exit()
741 	rec->ret = syscall_get_return_value(current, regs);  in perf_syscall_exit()
744 	     !perf_call_bpf_exit(sys_data->exit_event, fake_regs, rec)) ||  in perf_syscall_exit()
750 	perf_trace_buf_submit(rec, size, rctx, sys_data->exit_event->event.type,  in perf_syscall_exit()
754 static int perf_sysexit_enable(struct trace_event_call *call)  in perf_sysexit_enable()
759 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in perf_sysexit_enable()
765 		pr_info("event trace: Could not activate syscall exit trace point");  in perf_sysexit_enable()
774 static void perf_sysexit_disable(struct trace_event_call *call)  in perf_sysexit_disable()
778 	num = ((struct syscall_metadata *)call->data)->syscall_nr;  in perf_sysexit_disable()
781 	sys_perf_refcount_exit--;  in perf_sysexit_disable()
790 static int syscall_enter_register(struct trace_event_call *event,  in syscall_enter_register()
818 static int syscall_exit_register(struct trace_event_call *event,  in syscall_exit_register()