-/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
- *
- * lttng-syscalls.c
- *
- * LTTng syscall probes.
- *
- * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- */
-
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/compat.h>
-#include <linux/err.h>
-#include <linux/bitmap.h>
-#include <linux/in.h>
-#include <linux/in6.h>
-#include <linux/seq_file.h>
-#include <linux/stringify.h>
-#include <linux/file.h>
-#include <linux/anon_inodes.h>
-#include <linux/fcntl.h>
-#include <asm/ptrace.h>
-#include <asm/syscall.h>
-
-#include <lttng/bitfield.h>
-#include <wrapper/tracepoint.h>
-#include <wrapper/file.h>
-#include <wrapper/rcu.h>
-#include <wrapper/syscall.h>
-#include <lttng/events.h>
-
-#ifndef CONFIG_COMPAT
-# ifndef is_compat_task
-# define is_compat_task() (0)
-# endif
-#endif
-
-/* in_compat_syscall appears in kernel 4.6. */
-#ifndef in_compat_syscall
- #define in_compat_syscall() is_compat_task()
-#endif
-
-enum sc_type {
- SC_TYPE_ENTRY,
- SC_TYPE_EXIT,
- SC_TYPE_COMPAT_ENTRY,
- SC_TYPE_COMPAT_EXIT,
-};
-
-#define SYSCALL_ENTRY_TOK syscall_entry_
-#define COMPAT_SYSCALL_ENTRY_TOK compat_syscall_entry_
-#define SYSCALL_EXIT_TOK syscall_exit_
-#define COMPAT_SYSCALL_EXIT_TOK compat_syscall_exit_
-
-#define SYSCALL_ENTRY_STR __stringify(SYSCALL_ENTRY_TOK)
-#define COMPAT_SYSCALL_ENTRY_STR __stringify(COMPAT_SYSCALL_ENTRY_TOK)
-#define SYSCALL_EXIT_STR __stringify(SYSCALL_EXIT_TOK)
-#define COMPAT_SYSCALL_EXIT_STR __stringify(COMPAT_SYSCALL_EXIT_TOK)
-
-static
-void syscall_entry_probe(void *__data, struct pt_regs *regs, long id);
-static
-void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret);
-
-/*
- * Forward declarations for old kernels.
- */
-struct mmsghdr;
-struct rlimit64;
-struct oldold_utsname;
-struct old_utsname;
-struct sel_arg_struct;
-struct mmap_arg_struct;
-struct file_handle;
-struct user_msghdr;
-
-/*
- * Forward declaration for kernels >= 5.6
- */
-struct timex;
-struct timeval;
-struct itimerval;
-struct itimerspec;
-
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0))
-typedef __kernel_old_time_t time_t;
-#endif
-
-#ifdef IA32_NR_syscalls
-#define NR_compat_syscalls IA32_NR_syscalls
-#else
-#define NR_compat_syscalls NR_syscalls
-#endif
-
-/*
- * Create LTTng tracepoint probes.
- */
-#define LTTNG_PACKAGE_BUILD
-#define CREATE_TRACE_POINTS
-#define TP_MODULE_NOINIT
-#define TRACE_INCLUDE_PATH instrumentation/syscalls/headers
-
-#define PARAMS(args...) args
-
-/* Handle unknown syscalls */
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM syscalls_unknown
-#include <instrumentation/syscalls/headers/syscalls_unknown.h>
-#undef TRACE_SYSTEM
-
-#define SC_ENTER
-
-#undef sc_exit
-#define sc_exit(...)
-#undef sc_in
-#define sc_in(...) __VA_ARGS__
-#undef sc_out
-#define sc_out(...)
-#undef sc_inout
-#define sc_inout(...) __VA_ARGS__
-
-/* Hijack probe callback for system call enter */
-#undef TP_PROBE_CB
-#define TP_PROBE_CB(_template) &syscall_entry_probe
-#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \
- LTTNG_TRACEPOINT_EVENT(syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
- PARAMS(_fields))
-#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code_pre, _fields, _code_post) \
- LTTNG_TRACEPOINT_EVENT_CODE(syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
- PARAMS(_locvar), PARAMS(_code_pre), \
- PARAMS(_fields), PARAMS(_code_post))
-#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \
- LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_entry_##_name, PARAMS(_fields))
-#define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \
- LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_entry_##_template, syscall_entry_##_name)
-/* Enumerations only defined at first inclusion. */
-#define SC_LTTNG_TRACEPOINT_ENUM(_name, _values) \
- LTTNG_TRACEPOINT_ENUM(_name, PARAMS(_values))
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM syscall_entry_integers
-#define TRACE_INCLUDE_FILE syscalls_integers
-#include <instrumentation/syscalls/headers/syscalls_integers.h>
-#undef TRACE_INCLUDE_FILE
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM syscall_entry_pointers
-#define TRACE_INCLUDE_FILE syscalls_pointers
-#include <instrumentation/syscalls/headers/syscalls_pointers.h>
-#undef TRACE_INCLUDE_FILE
-#undef TRACE_SYSTEM
-#undef SC_LTTNG_TRACEPOINT_ENUM
-#undef SC_LTTNG_TRACEPOINT_EVENT_CODE
-#undef SC_LTTNG_TRACEPOINT_EVENT
-#undef SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS
-#undef SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS
-#undef TP_PROBE_CB
-#undef _TRACE_SYSCALLS_INTEGERS_H
-#undef _TRACE_SYSCALLS_POINTERS_H
-
-/* Hijack probe callback for compat system call enter */
-#define TP_PROBE_CB(_template) &syscall_entry_probe
-#define LTTNG_SC_COMPAT
-#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \
- LTTNG_TRACEPOINT_EVENT(compat_syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
- PARAMS(_fields))
-#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code_pre, _fields, _code_post) \
- LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
- PARAMS(_locvar), PARAMS(_code_pre), PARAMS(_fields), PARAMS(_code_post))
-#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \
- LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_entry_##_name, PARAMS(_fields))
-#define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \
- LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_entry_##_template, \
- compat_syscall_entry_##_name)
-/* Enumerations only defined at inital inclusion (not here). */
-#define SC_LTTNG_TRACEPOINT_ENUM(_name, _values)
-#define TRACE_SYSTEM compat_syscall_entry_integers
-#define TRACE_INCLUDE_FILE compat_syscalls_integers
-#include <instrumentation/syscalls/headers/compat_syscalls_integers.h>
-#undef TRACE_INCLUDE_FILE
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM compat_syscall_entry_pointers
-#define TRACE_INCLUDE_FILE compat_syscalls_pointers
-#include <instrumentation/syscalls/headers/compat_syscalls_pointers.h>
-#undef TRACE_INCLUDE_FILE
-#undef TRACE_SYSTEM
-#undef SC_LTTNG_TRACEPOINT_ENUM
-#undef SC_LTTNG_TRACEPOINT_EVENT_CODE
-#undef SC_LTTNG_TRACEPOINT_EVENT
-#undef SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS
-#undef SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS
-#undef TP_PROBE_CB
-#undef _TRACE_SYSCALLS_INTEGERS_H
-#undef _TRACE_SYSCALLS_POINTERS_H
-#undef LTTNG_SC_COMPAT
-
-#undef SC_ENTER
-
-#define SC_EXIT
-
-#undef sc_exit
-#define sc_exit(...) __VA_ARGS__
-#undef sc_in
-#define sc_in(...)
-#undef sc_out
-#define sc_out(...) __VA_ARGS__
-#undef sc_inout
-#define sc_inout(...) __VA_ARGS__
-
-/* Hijack probe callback for system call exit */
-#define TP_PROBE_CB(_template) &syscall_exit_probe
-#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \
- LTTNG_TRACEPOINT_EVENT(syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
- PARAMS(_fields))
-#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code_pre, _fields, _code_post) \
- LTTNG_TRACEPOINT_EVENT_CODE(syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
- PARAMS(_locvar), PARAMS(_code_pre), PARAMS(_fields), PARAMS(_code_post))
-#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \
- LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_exit_##_name, PARAMS(_fields))
-#define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \
- LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_exit_##_template, \
- syscall_exit_##_name)
-/* Enumerations only defined at inital inclusion (not here). */
-#define SC_LTTNG_TRACEPOINT_ENUM(_name, _values)
-#define TRACE_SYSTEM syscall_exit_integers
-#define TRACE_INCLUDE_FILE syscalls_integers
-#include <instrumentation/syscalls/headers/syscalls_integers.h>
-#undef TRACE_INCLUDE_FILE
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM syscall_exit_pointers
-#define TRACE_INCLUDE_FILE syscalls_pointers
-#include <instrumentation/syscalls/headers/syscalls_pointers.h>
-#undef TRACE_INCLUDE_FILE
-#undef TRACE_SYSTEM
-#undef SC_LTTNG_TRACEPOINT_ENUM
-#undef SC_LTTNG_TRACEPOINT_EVENT_CODE
-#undef SC_LTTNG_TRACEPOINT_EVENT
-#undef SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS
-#undef SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS
-#undef TP_PROBE_CB
-#undef _TRACE_SYSCALLS_INTEGERS_H
-#undef _TRACE_SYSCALLS_POINTERS_H
-
-
-/* Hijack probe callback for compat system call exit */
-#define TP_PROBE_CB(_template) &syscall_exit_probe
-#define LTTNG_SC_COMPAT
-#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \
- LTTNG_TRACEPOINT_EVENT(compat_syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
- PARAMS(_fields))
-#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code_pre, _fields, _code_post) \
- LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
- PARAMS(_locvar), PARAMS(_code_pre), PARAMS(_fields), PARAMS(_code_post))
-#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \
- LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_exit_##_name, PARAMS(_fields))
-#define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \
- LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_exit_##_template, \
- compat_syscall_exit_##_name)
-/* Enumerations only defined at inital inclusion (not here). */
-#define SC_LTTNG_TRACEPOINT_ENUM(_name, _values)
-#define TRACE_SYSTEM compat_syscall_exit_integers
-#define TRACE_INCLUDE_FILE compat_syscalls_integers
-#include <instrumentation/syscalls/headers/compat_syscalls_integers.h>
-#undef TRACE_INCLUDE_FILE
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM compat_syscall_exit_pointers
-#define TRACE_INCLUDE_FILE compat_syscalls_pointers
-#include <instrumentation/syscalls/headers/compat_syscalls_pointers.h>
-#undef TRACE_INCLUDE_FILE
-#undef TRACE_SYSTEM
-#undef SC_LTTNG_TRACEPOINT_ENUM
-#undef SC_LTTNG_TRACEPOINT_EVENT_CODE
-#undef SC_LTTNG_TRACEPOINT_EVENT
-#undef SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS
-#undef SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS
-#undef TP_PROBE_CB
-#undef _TRACE_SYSCALLS_INTEGERS_H
-#undef _TRACE_SYSCALLS_POINTERS_H
-#undef LTTNG_SC_COMPAT
-
-#undef SC_EXIT
-
-#undef TP_MODULE_NOINIT
-#undef LTTNG_PACKAGE_BUILD
-#undef CREATE_TRACE_POINTS
-
-struct trace_syscall_entry {
- void *func;
- const struct lttng_event_desc *desc;
- const struct lttng_event_field *fields;
- unsigned int nrargs;
-};
-
-#define CREATE_SYSCALL_TABLE
-
-#define SC_ENTER
-
-#undef sc_exit
-#define sc_exit(...)
-
-#undef TRACE_SYSCALL_TABLE
-#define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \
- [ _nr ] = { \
- .func = __event_probe__syscall_entry_##_template, \
- .nrargs = (_nrargs), \
- .fields = __event_fields___syscall_entry_##_template, \
- .desc = &__event_desc___syscall_entry_##_name, \
- },
-
-/* Syscall enter tracing table */
-static const struct trace_syscall_entry sc_table[] = {
-#include <instrumentation/syscalls/headers/syscalls_integers.h>
-#include <instrumentation/syscalls/headers/syscalls_pointers.h>
-};
-
-#undef TRACE_SYSCALL_TABLE
-#define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \
- [ _nr ] = { \
- .func = __event_probe__compat_syscall_entry_##_template, \
- .nrargs = (_nrargs), \
- .fields = __event_fields___compat_syscall_entry_##_template, \
- .desc = &__event_desc___compat_syscall_entry_##_name, \
- },
-
-/* Compat syscall enter table */
-const struct trace_syscall_entry compat_sc_table[] = {
-#include <instrumentation/syscalls/headers/compat_syscalls_integers.h>
-#include <instrumentation/syscalls/headers/compat_syscalls_pointers.h>
-};
-
-#undef SC_ENTER
-
-#define SC_EXIT
-
-#undef sc_exit
-#define sc_exit(...) __VA_ARGS__
-
-#undef TRACE_SYSCALL_TABLE
-#define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \
- [ _nr ] = { \
- .func = __event_probe__syscall_exit_##_template, \
- .nrargs = (_nrargs), \
- .fields = __event_fields___syscall_exit_##_template, \
- .desc = &__event_desc___syscall_exit_##_name, \
- },
-
-/* Syscall exit table */
-static const struct trace_syscall_entry sc_exit_table[] = {
-#include <instrumentation/syscalls/headers/syscalls_integers.h>
-#include <instrumentation/syscalls/headers/syscalls_pointers.h>
-};
-
-#undef TRACE_SYSCALL_TABLE
-#define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \
- [ _nr ] = { \
- .func = __event_probe__compat_syscall_exit_##_template, \
- .nrargs = (_nrargs), \
- .fields = __event_fields___compat_syscall_exit_##_template, \
- .desc = &__event_desc___compat_syscall_exit_##_name, \
- },
-
-/* Compat syscall exit table */
-const struct trace_syscall_entry compat_sc_exit_table[] = {
-#include <instrumentation/syscalls/headers/compat_syscalls_integers.h>
-#include <instrumentation/syscalls/headers/compat_syscalls_pointers.h>
-};
-
-#undef SC_EXIT
-
-#undef CREATE_SYSCALL_TABLE
-
-struct lttng_syscall_filter {
- DECLARE_BITMAP(sc, NR_syscalls);
- DECLARE_BITMAP(sc_compat, NR_compat_syscalls);
-};
-
-static void syscall_entry_unknown(struct lttng_event *event,
- struct pt_regs *regs, unsigned int id)
-{
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- if (unlikely(in_compat_syscall()))
- __event_probe__compat_syscall_entry_unknown(event, id, args);
- else
- __event_probe__syscall_entry_unknown(event, id, args);
-}
-
-void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
-{
- struct lttng_channel *chan = __data;
- struct lttng_event *event, *unknown_event;
- const struct trace_syscall_entry *table, *entry;
- size_t table_len;
-
- if (unlikely(in_compat_syscall())) {
- struct lttng_syscall_filter *filter;
-
- filter = lttng_rcu_dereference(chan->sc_filter);
- if (filter) {
- if (id < 0 || id >= NR_compat_syscalls
- || !test_bit(id, filter->sc_compat)) {
- /* System call filtered out. */
- return;
- }
- }
- table = compat_sc_table;
- table_len = ARRAY_SIZE(compat_sc_table);
- unknown_event = chan->sc_compat_unknown;
- } else {
- struct lttng_syscall_filter *filter;
-
- filter = lttng_rcu_dereference(chan->sc_filter);
- if (filter) {
- if (id < 0 || id >= NR_syscalls
- || !test_bit(id, filter->sc)) {
- /* System call filtered out. */
- return;
- }
- }
- table = sc_table;
- table_len = ARRAY_SIZE(sc_table);
- unknown_event = chan->sc_unknown;
- }
- if (unlikely(id < 0 || id >= table_len)) {
- syscall_entry_unknown(unknown_event, regs, id);
- return;
- }
- if (unlikely(in_compat_syscall()))
- event = chan->compat_sc_table[id];
- else
- event = chan->sc_table[id];
- if (unlikely(!event)) {
- syscall_entry_unknown(unknown_event, regs, id);
- return;
- }
- entry = &table[id];
- WARN_ON_ONCE(!entry);
-
- switch (entry->nrargs) {
- case 0:
- {
- void (*fptr)(void *__data) = entry->func;
-
- fptr(event);
- break;
- }
- case 1:
- {
- void (*fptr)(void *__data, unsigned long arg0) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, args[0]);
- break;
- }
- case 2:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, args[0], args[1]);
- break;
- }
- case 3:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, args[0], args[1], args[2]);
- break;
- }
- case 4:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, args[0], args[1], args[2], args[3]);
- break;
- }
- case 5:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3,
- unsigned long arg4) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, args[0], args[1], args[2], args[3], args[4]);
- break;
- }
- case 6:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3,
- unsigned long arg4,
- unsigned long arg5) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, args[0], args[1], args[2],
- args[3], args[4], args[5]);
- break;
- }
- default:
- break;
- }
-}
-
-static void syscall_exit_unknown(struct lttng_event *event,
- struct pt_regs *regs, int id, long ret)
-{
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- if (unlikely(in_compat_syscall()))
- __event_probe__compat_syscall_exit_unknown(event, id, ret,
- args);
- else
- __event_probe__syscall_exit_unknown(event, id, ret, args);
-}
-
-void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret)
-{
- struct lttng_channel *chan = __data;
- struct lttng_event *event, *unknown_event;
- const struct trace_syscall_entry *table, *entry;
- size_t table_len;
- long id;
-
- id = syscall_get_nr(current, regs);
- if (unlikely(in_compat_syscall())) {
- struct lttng_syscall_filter *filter;
-
- filter = lttng_rcu_dereference(chan->sc_filter);
- if (filter) {
- if (id < 0 || id >= NR_compat_syscalls
- || !test_bit(id, filter->sc_compat)) {
- /* System call filtered out. */
- return;
- }
- }
- table = compat_sc_exit_table;
- table_len = ARRAY_SIZE(compat_sc_exit_table);
- unknown_event = chan->compat_sc_exit_unknown;
- } else {
- struct lttng_syscall_filter *filter;
-
- filter = lttng_rcu_dereference(chan->sc_filter);
- if (filter) {
- if (id < 0 || id >= NR_syscalls
- || !test_bit(id, filter->sc)) {
- /* System call filtered out. */
- return;
- }
- }
- table = sc_exit_table;
- table_len = ARRAY_SIZE(sc_exit_table);
- unknown_event = chan->sc_exit_unknown;
- }
- if (unlikely(id < 0 || id >= table_len)) {
- syscall_exit_unknown(unknown_event, regs, id, ret);
- return;
- }
- if (unlikely(in_compat_syscall()))
- event = chan->compat_sc_exit_table[id];
- else
- event = chan->sc_exit_table[id];
- if (unlikely(!event)) {
- syscall_exit_unknown(unknown_event, regs, id, ret);
- return;
- }
- entry = &table[id];
- WARN_ON_ONCE(!entry);
-
- switch (entry->nrargs) {
- case 0:
- {
- void (*fptr)(void *__data, long ret) = entry->func;
-
- fptr(event, ret);
- break;
- }
- case 1:
- {
- void (*fptr)(void *__data,
- long ret,
- unsigned long arg0) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, ret, args[0]);
- break;
- }
- case 2:
- {
- void (*fptr)(void *__data,
- long ret,
- unsigned long arg0,
- unsigned long arg1) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, ret, args[0], args[1]);
- break;
- }
- case 3:
- {
- void (*fptr)(void *__data,
- long ret,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, ret, args[0], args[1], args[2]);
- break;
- }
- case 4:
- {
- void (*fptr)(void *__data,
- long ret,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, ret, args[0], args[1], args[2], args[3]);
- break;
- }
- case 5:
- {
- void (*fptr)(void *__data,
- long ret,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3,
- unsigned long arg4) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, ret, args[0], args[1], args[2], args[3], args[4]);
- break;
- }
- case 6:
- {
- void (*fptr)(void *__data,
- long ret,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3,
- unsigned long arg4,
- unsigned long arg5) = entry->func;
- unsigned long args[LTTNG_SYSCALL_NR_ARGS];
-
- lttng_syscall_get_arguments(current, regs, args);
- fptr(event, ret, args[0], args[1], args[2],
- args[3], args[4], args[5]);
- break;
- }
- default:
- break;
- }
-}
-
-/*
- * noinline to diminish caller stack size.
- * Should be called with sessions lock held.
- */
-static
-int fill_table(const struct trace_syscall_entry *table, size_t table_len,
- struct lttng_event **chan_table, struct lttng_channel *chan,
- void *filter, enum sc_type type)
-{
- const struct lttng_event_desc *desc;
- unsigned int i;
-
- /* Allocate events for each syscall, insert into table */
- for (i = 0; i < table_len; i++) {
- struct lttng_kernel_event ev;
- desc = table[i].desc;
-
- if (!desc) {
- /* Unknown syscall */
- continue;
- }
- /*
- * Skip those already populated by previous failed
- * register for this channel.
- */
- if (chan_table[i])
- continue;
- memset(&ev, 0, sizeof(ev));
- switch (type) {
- case SC_TYPE_ENTRY:
- strncpy(ev.name, SYSCALL_ENTRY_STR,
- LTTNG_KERNEL_SYM_NAME_LEN);
- break;
- case SC_TYPE_EXIT:
- strncpy(ev.name, SYSCALL_EXIT_STR,
- LTTNG_KERNEL_SYM_NAME_LEN);
- break;
- case SC_TYPE_COMPAT_ENTRY:
- strncpy(ev.name, COMPAT_SYSCALL_ENTRY_STR,
- LTTNG_KERNEL_SYM_NAME_LEN);
- break;
- case SC_TYPE_COMPAT_EXIT:
- strncpy(ev.name, COMPAT_SYSCALL_EXIT_STR,
- LTTNG_KERNEL_SYM_NAME_LEN);
- break;
- default:
- BUG_ON(1);
- break;
- }
- strncat(ev.name, desc->name,
- LTTNG_KERNEL_SYM_NAME_LEN - strlen(ev.name) - 1);
- ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
- ev.instrumentation = LTTNG_KERNEL_SYSCALL;
- chan_table[i] = _lttng_event_create(chan, &ev, filter,
- desc, ev.instrumentation);
- WARN_ON_ONCE(!chan_table[i]);
- if (IS_ERR(chan_table[i])) {
- /*
- * If something goes wrong in event registration
- * after the first one, we have no choice but to
- * leave the previous events in there, until
- * deleted by session teardown.
- */
- return PTR_ERR(chan_table[i]);
- }
- }
- return 0;
-}
-
-/*
- * Should be called with sessions lock held.
- */
-int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
-{
- struct lttng_kernel_event ev;
- int ret;
-
- wrapper_vmalloc_sync_mappings();
-
- if (!chan->sc_table) {
- /* create syscall table mapping syscall to events */
- chan->sc_table = kzalloc(sizeof(struct lttng_event *)
- * ARRAY_SIZE(sc_table), GFP_KERNEL);
- if (!chan->sc_table)
- return -ENOMEM;
- }
- if (!chan->sc_exit_table) {
- /* create syscall table mapping syscall to events */
- chan->sc_exit_table = kzalloc(sizeof(struct lttng_event *)
- * ARRAY_SIZE(sc_exit_table), GFP_KERNEL);
- if (!chan->sc_exit_table)
- return -ENOMEM;
- }
-
-
-#ifdef CONFIG_COMPAT
- if (!chan->compat_sc_table) {
- /* create syscall table mapping compat syscall to events */
- chan->compat_sc_table = kzalloc(sizeof(struct lttng_event *)
- * ARRAY_SIZE(compat_sc_table), GFP_KERNEL);
- if (!chan->compat_sc_table)
- return -ENOMEM;
- }
-
- if (!chan->compat_sc_exit_table) {
- /* create syscall table mapping compat syscall to events */
- chan->compat_sc_exit_table = kzalloc(sizeof(struct lttng_event *)
- * ARRAY_SIZE(compat_sc_exit_table), GFP_KERNEL);
- if (!chan->compat_sc_exit_table)
- return -ENOMEM;
- }
-#endif
- if (!chan->sc_unknown) {
- const struct lttng_event_desc *desc =
- &__event_desc___syscall_entry_unknown;
-
- memset(&ev, 0, sizeof(ev));
- strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
- ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
- ev.instrumentation = LTTNG_KERNEL_SYSCALL;
- chan->sc_unknown = _lttng_event_create(chan, &ev, filter,
- desc,
- ev.instrumentation);
- WARN_ON_ONCE(!chan->sc_unknown);
- if (IS_ERR(chan->sc_unknown)) {
- return PTR_ERR(chan->sc_unknown);
- }
- }
-
- if (!chan->sc_compat_unknown) {
- const struct lttng_event_desc *desc =
- &__event_desc___compat_syscall_entry_unknown;
-
- memset(&ev, 0, sizeof(ev));
- strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
- ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
- ev.instrumentation = LTTNG_KERNEL_SYSCALL;
- chan->sc_compat_unknown = _lttng_event_create(chan, &ev, filter,
- desc,
- ev.instrumentation);
- WARN_ON_ONCE(!chan->sc_unknown);
- if (IS_ERR(chan->sc_compat_unknown)) {
- return PTR_ERR(chan->sc_compat_unknown);
- }
- }
-
- if (!chan->compat_sc_exit_unknown) {
- const struct lttng_event_desc *desc =
- &__event_desc___compat_syscall_exit_unknown;
-
- memset(&ev, 0, sizeof(ev));
- strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
- ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
- ev.instrumentation = LTTNG_KERNEL_SYSCALL;
- chan->compat_sc_exit_unknown = _lttng_event_create(chan, &ev,
- filter, desc,
- ev.instrumentation);
- WARN_ON_ONCE(!chan->compat_sc_exit_unknown);
- if (IS_ERR(chan->compat_sc_exit_unknown)) {
- return PTR_ERR(chan->compat_sc_exit_unknown);
- }
- }
-
- if (!chan->sc_exit_unknown) {
- const struct lttng_event_desc *desc =
- &__event_desc___syscall_exit_unknown;
-
- memset(&ev, 0, sizeof(ev));
- strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
- ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
- ev.instrumentation = LTTNG_KERNEL_SYSCALL;
- chan->sc_exit_unknown = _lttng_event_create(chan, &ev, filter,
- desc, ev.instrumentation);
- WARN_ON_ONCE(!chan->sc_exit_unknown);
- if (IS_ERR(chan->sc_exit_unknown)) {
- return PTR_ERR(chan->sc_exit_unknown);
- }
- }
-
- ret = fill_table(sc_table, ARRAY_SIZE(sc_table),
- chan->sc_table, chan, filter, SC_TYPE_ENTRY);
- if (ret)
- return ret;
- ret = fill_table(sc_exit_table, ARRAY_SIZE(sc_exit_table),
- chan->sc_exit_table, chan, filter, SC_TYPE_EXIT);
- if (ret)
- return ret;
-
-#ifdef CONFIG_COMPAT
- ret = fill_table(compat_sc_table, ARRAY_SIZE(compat_sc_table),
- chan->compat_sc_table, chan, filter,
- SC_TYPE_COMPAT_ENTRY);
- if (ret)
- return ret;
- ret = fill_table(compat_sc_exit_table, ARRAY_SIZE(compat_sc_exit_table),
- chan->compat_sc_exit_table, chan, filter,
- SC_TYPE_COMPAT_EXIT);
- if (ret)
- return ret;
-#endif
- if (!chan->sys_enter_registered) {
- ret = lttng_wrapper_tracepoint_probe_register("sys_enter",
- (void *) syscall_entry_probe, chan);
- if (ret)
- return ret;
- chan->sys_enter_registered = 1;
- }
- /*
- * We change the name of sys_exit tracepoint due to namespace
- * conflict with sys_exit syscall entry.
- */
- if (!chan->sys_exit_registered) {
- ret = lttng_wrapper_tracepoint_probe_register("sys_exit",
- (void *) syscall_exit_probe, chan);
- if (ret) {
- WARN_ON_ONCE(lttng_wrapper_tracepoint_probe_unregister("sys_enter",
- (void *) syscall_entry_probe, chan));
- return ret;
- }
- chan->sys_exit_registered = 1;
- }
- return ret;
-}
-
-/*
- * Only called at session destruction.
- */
-int lttng_syscalls_unregister(struct lttng_channel *chan)
-{
- int ret;
-
- if (!chan->sc_table)
- return 0;
- if (chan->sys_enter_registered) {
- ret = lttng_wrapper_tracepoint_probe_unregister("sys_enter",
- (void *) syscall_entry_probe, chan);
- if (ret)
- return ret;
- chan->sys_enter_registered = 0;
- }
- if (chan->sys_exit_registered) {
- ret = lttng_wrapper_tracepoint_probe_unregister("sys_exit",
- (void *) syscall_exit_probe, chan);
- if (ret)
- return ret;
- chan->sys_exit_registered = 0;
- }
- /* lttng_event destroy will be performed by lttng_session_destroy() */
- kfree(chan->sc_table);
- kfree(chan->sc_exit_table);
-#ifdef CONFIG_COMPAT
- kfree(chan->compat_sc_table);
- kfree(chan->compat_sc_exit_table);
-#endif
- kfree(chan->sc_filter);
- return 0;
-}
-
-static
-int get_syscall_nr(const char *syscall_name)
-{
- int syscall_nr = -1;
- int i;
-
- for (i = 0; i < ARRAY_SIZE(sc_table); i++) {
- const struct trace_syscall_entry *entry;
- const char *it_name;
-
- entry = &sc_table[i];
- if (!entry->desc)
- continue;
- it_name = entry->desc->name;
- it_name += strlen(SYSCALL_ENTRY_STR);
- if (!strcmp(syscall_name, it_name)) {
- syscall_nr = i;
- break;
- }
- }
- return syscall_nr;
-}
-
-static
-int get_compat_syscall_nr(const char *syscall_name)
-{
- int syscall_nr = -1;
- int i;
-
- for (i = 0; i < ARRAY_SIZE(compat_sc_table); i++) {
- const struct trace_syscall_entry *entry;
- const char *it_name;
-
- entry = &compat_sc_table[i];
- if (!entry->desc)
- continue;
- it_name = entry->desc->name;
- it_name += strlen(COMPAT_SYSCALL_ENTRY_STR);
- if (!strcmp(syscall_name, it_name)) {
- syscall_nr = i;
- break;
- }
- }
- return syscall_nr;
-}
-
-static
-uint32_t get_sc_tables_len(void)
-{
- return ARRAY_SIZE(sc_table) + ARRAY_SIZE(compat_sc_table);
-}
-
-int lttng_syscall_filter_enable(struct lttng_channel *chan,
- const char *name)
-{
- int syscall_nr, compat_syscall_nr, ret;
- struct lttng_syscall_filter *filter;
-
- WARN_ON_ONCE(!chan->sc_table);
-
- if (!name) {
- /* Enable all system calls by removing filter */
- if (chan->sc_filter) {
- filter = chan->sc_filter;
- rcu_assign_pointer(chan->sc_filter, NULL);
- synchronize_trace();
- kfree(filter);
- }
- chan->syscall_all = 1;
- return 0;
- }
-
- if (!chan->sc_filter) {
- if (chan->syscall_all) {
- /*
- * All syscalls are already enabled.
- */
- return -EEXIST;
- }
- filter = kzalloc(sizeof(struct lttng_syscall_filter),
- GFP_KERNEL);
- if (!filter)
- return -ENOMEM;
- } else {
- filter = chan->sc_filter;
- }
- syscall_nr = get_syscall_nr(name);
- compat_syscall_nr = get_compat_syscall_nr(name);
- if (syscall_nr < 0 && compat_syscall_nr < 0) {
- ret = -ENOENT;
- goto error;
- }
- if (syscall_nr >= 0) {
- if (test_bit(syscall_nr, filter->sc)) {
- ret = -EEXIST;
- goto error;
- }
- bitmap_set(filter->sc, syscall_nr, 1);
- }
- if (compat_syscall_nr >= 0) {
- if (test_bit(compat_syscall_nr, filter->sc_compat)) {
- ret = -EEXIST;
- goto error;
- }
- bitmap_set(filter->sc_compat, compat_syscall_nr, 1);
- }
- if (!chan->sc_filter)
- rcu_assign_pointer(chan->sc_filter, filter);
- return 0;
-
-error:
- if (!chan->sc_filter)
- kfree(filter);
- return ret;
-}
-
-int lttng_syscall_filter_disable(struct lttng_channel *chan,
- const char *name)
-{
- int syscall_nr, compat_syscall_nr, ret;
- struct lttng_syscall_filter *filter;
-
- WARN_ON_ONCE(!chan->sc_table);
-
- if (!chan->sc_filter) {
- if (!chan->syscall_all)
- return -EEXIST;
- filter = kzalloc(sizeof(struct lttng_syscall_filter),
- GFP_KERNEL);
- if (!filter)
- return -ENOMEM;
- /* Trace all system calls, then apply disable. */
- bitmap_set(filter->sc, 0, NR_syscalls);
- bitmap_set(filter->sc_compat, 0, NR_compat_syscalls);
- } else {
- filter = chan->sc_filter;
- }
-
- if (!name) {
- /* Fail if all syscalls are already disabled. */
- if (bitmap_empty(filter->sc, NR_syscalls)
- && bitmap_empty(filter->sc_compat,
- NR_compat_syscalls)) {
- ret = -EEXIST;
- goto error;
- }
-
- /* Disable all system calls */
- bitmap_clear(filter->sc, 0, NR_syscalls);
- bitmap_clear(filter->sc_compat, 0, NR_compat_syscalls);
- goto apply_filter;
- }
- syscall_nr = get_syscall_nr(name);
- compat_syscall_nr = get_compat_syscall_nr(name);
- if (syscall_nr < 0 && compat_syscall_nr < 0) {
- ret = -ENOENT;
- goto error;
- }
- if (syscall_nr >= 0) {
- if (!test_bit(syscall_nr, filter->sc)) {
- ret = -EEXIST;
- goto error;
- }
- bitmap_clear(filter->sc, syscall_nr, 1);
- }
- if (compat_syscall_nr >= 0) {
- if (!test_bit(compat_syscall_nr, filter->sc_compat)) {
- ret = -EEXIST;
- goto error;
- }
- bitmap_clear(filter->sc_compat, compat_syscall_nr, 1);
- }
-apply_filter:
- if (!chan->sc_filter)
- rcu_assign_pointer(chan->sc_filter, filter);
- chan->syscall_all = 0;
- return 0;
-
-error:
- if (!chan->sc_filter)
- kfree(filter);
- return ret;
-}
-
-static
-const struct trace_syscall_entry *syscall_list_get_entry(loff_t *pos)
-{
- const struct trace_syscall_entry *entry;
- int iter = 0;
-
- for (entry = sc_table;
- entry < sc_table + ARRAY_SIZE(sc_table);
- entry++) {
- if (iter++ >= *pos)
- return entry;
- }
- for (entry = compat_sc_table;
- entry < compat_sc_table + ARRAY_SIZE(compat_sc_table);
- entry++) {
- if (iter++ >= *pos)
- return entry;
- }
- /* End of list */
- return NULL;
-}
-
-static
-void *syscall_list_start(struct seq_file *m, loff_t *pos)
-{
- return (void *) syscall_list_get_entry(pos);
-}
-
-static
-void *syscall_list_next(struct seq_file *m, void *p, loff_t *ppos)
-{
- (*ppos)++;
- return (void *) syscall_list_get_entry(ppos);
-}
-
-static
-void syscall_list_stop(struct seq_file *m, void *p)
-{
-}
-
-static
-int get_sc_table(const struct trace_syscall_entry *entry,
- const struct trace_syscall_entry **table,
- unsigned int *bitness)
-{
- if (entry >= sc_table && entry < sc_table + ARRAY_SIZE(sc_table)) {
- if (bitness)
- *bitness = BITS_PER_LONG;
- if (table)
- *table = sc_table;
- return 0;
- }
- if (!(entry >= compat_sc_table
- && entry < compat_sc_table + ARRAY_SIZE(compat_sc_table))) {
- return -EINVAL;
- }
- if (bitness)
- *bitness = 32;
- if (table)
- *table = compat_sc_table;
- return 0;
-}
-
-static
-int syscall_list_show(struct seq_file *m, void *p)
-{
- const struct trace_syscall_entry *table, *entry = p;
- unsigned int bitness;
- unsigned long index;
- int ret;
- const char *name;
-
- ret = get_sc_table(entry, &table, &bitness);
- if (ret)
- return ret;
- if (!entry->desc)
- return 0;
- if (table == sc_table) {
- index = entry - table;
- name = &entry->desc->name[strlen(SYSCALL_ENTRY_STR)];
- } else {
- index = (entry - table) + ARRAY_SIZE(sc_table);
- name = &entry->desc->name[strlen(COMPAT_SYSCALL_ENTRY_STR)];
- }
- seq_printf(m, "syscall { index = %lu; name = %s; bitness = %u; };\n",
- index, name, bitness);
- return 0;
-}
-
-static
-const struct seq_operations lttng_syscall_list_seq_ops = {
- .start = syscall_list_start,
- .next = syscall_list_next,
- .stop = syscall_list_stop,
- .show = syscall_list_show,
-};
-
-static
-int lttng_syscall_list_open(struct inode *inode, struct file *file)
-{
- return seq_open(file, <tng_syscall_list_seq_ops);
-}
-
-const struct file_operations lttng_syscall_list_fops = {
- .owner = THIS_MODULE,
- .open = lttng_syscall_list_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
-};
-
-long lttng_channel_syscall_mask(struct lttng_channel *channel,
- struct lttng_kernel_syscall_mask __user *usyscall_mask)
-{
- uint32_t len, sc_tables_len, bitmask_len;
- int ret = 0, bit;
- char *tmp_mask;
- struct lttng_syscall_filter *filter;
-
- ret = get_user(len, &usyscall_mask->len);
- if (ret)
- return ret;
- sc_tables_len = get_sc_tables_len();
- bitmask_len = ALIGN(sc_tables_len, 8) >> 3;
- if (len < sc_tables_len) {
- return put_user(sc_tables_len, &usyscall_mask->len);
- }
- /* Array is large enough, we can copy array to user-space. */
- tmp_mask = kzalloc(bitmask_len, GFP_KERNEL);
- if (!tmp_mask)
- return -ENOMEM;
- filter = channel->sc_filter;
-
- for (bit = 0; bit < ARRAY_SIZE(sc_table); bit++) {
- char state;
-
- if (channel->sc_table) {
- if (filter)
- state = test_bit(bit, filter->sc);
- else
- state = 1;
- } else {
- state = 0;
- }
- bt_bitfield_write_be(tmp_mask, char, bit, 1, state);
- }
- for (; bit < sc_tables_len; bit++) {
- char state;
-
- if (channel->compat_sc_table) {
- if (filter)
- state = test_bit(bit - ARRAY_SIZE(sc_table),
- filter->sc_compat);
- else
- state = 1;
- } else {
- state = 0;
- }
- bt_bitfield_write_be(tmp_mask, char, bit, 1, state);
- }
- if (copy_to_user(usyscall_mask->mask, tmp_mask, bitmask_len))
- ret = -EFAULT;
- kfree(tmp_mask);
- return ret;
-}
-
-int lttng_abi_syscall_list(void)
-{
- struct file *syscall_list_file;
- int file_fd, ret;
-
- file_fd = lttng_get_unused_fd();
- if (file_fd < 0) {
- ret = file_fd;
- goto fd_error;
- }
-
- syscall_list_file = anon_inode_getfile("[lttng_syscall_list]",
- <tng_syscall_list_fops,
- NULL, O_RDWR);
- if (IS_ERR(syscall_list_file)) {
- ret = PTR_ERR(syscall_list_file);
- goto file_error;
- }
- ret = lttng_syscall_list_fops.open(NULL, syscall_list_file);
- if (ret < 0)
- goto open_error;
- fd_install(file_fd, syscall_list_file);
- return file_fd;
-
-open_error:
- fput(syscall_list_file);
-file_error:
- put_unused_fd(file_fd);
-fd_error:
- return ret;
-}