/*
* lttng-syscalls.c
*
- * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * LTTng syscall probes.
*
- * LTTng sched probes.
+ * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
- * Dual LGPL v2.1/GPL v2 license.
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; only
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#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 <asm/ptrace.h>
#include <asm/syscall.h>
-#include "ltt-events.h"
+#include "lib/bitfield.h"
+#include "wrapper/tracepoint.h"
+#include "wrapper/file.h"
+#include "lttng-events.h"
+
+#ifndef CONFIG_COMPAT
+# ifndef is_compat_task
+# define is_compat_task() (0)
+# endif
+#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_
-static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id);
+#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;
+
+#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
-/* Hijack probe callback for system calls */
+#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 TP_MODULE_OVERRIDE
+#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT(syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT_CODE(syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_locvar), PARAMS(_code), \
+ PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_entry_##_name, PARAMS(_struct), PARAMS(_assign), \
+ PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \
+ LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_entry_##_template, syscall_entry_##_name)
+#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_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
-#define TRACE_INCLUDE_PATH ../instrumentation/syscalls/headers
+/* Hijack probe callback for compat system call enter */
+#define TP_PROBE_CB(_template) &syscall_entry_probe
+#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT(compat_syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_struct), PARAMS(_assign), \
+ PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_locvar), PARAMS(_code), \
+ PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_entry_##_name, PARAMS(_struct), \
+ PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \
+ LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_entry_##_template, \
+ compat_syscall_entry_##_name)
+#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_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 SC_ENTER
+
+#define SC_EXIT
-#include "instrumentation/syscalls/headers/syscalls.h"
+#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__
-#undef TP_MODULE_OVERRIDE
+/* Hijack probe callback for system call exit */
+#define TP_PROBE_CB(_template) &syscall_exit_probe
+#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT(syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT_CODE(syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_locvar), PARAMS(_code), \
+ PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_exit_##_name, PARAMS(_struct), \
+ PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \
+ LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_exit_##_template, \
+ syscall_exit_##_name)
+#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_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 SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT(compat_syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_locvar), PARAMS(_code), \
+ PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
+ LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_exit_##_name, PARAMS(_struct), \
+ PARAMS(_assign), PARAMS(_printk))
+#define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \
+ LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_exit_##_template, \
+ compat_syscall_exit_##_name)
+#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_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 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; /* Set dynamically */
+ const struct lttng_event_desc *desc;
const struct lttng_event_field *fields;
unsigned int nrargs;
};
-static int sc_table_desc_filled;
-
#define CREATE_SYSCALL_TABLE
+#define SC_ENTER
+
+#undef sc_exit
+#define sc_exit(...)
+
#undef TRACE_SYSCALL_TABLE
-#define TRACE_SYSCALL_TABLE(_name, _nr, _nrargs) \
+#define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \
[ _nr ] = { \
- .func = __event_probe__##_name, \
+ .func = __event_probe__syscall_entry_##_template, \
.nrargs = (_nrargs), \
- .fields = __event_fields___##_name, \
+ .fields = __event_fields___syscall_entry_##_template, \
+ .desc = &__event_desc___syscall_entry_##_name, \
},
-static struct trace_syscall_entry sc_table[] = {
-#include "instrumentation/syscalls/headers/syscalls.h"
+/* 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
-static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
+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)
{
- struct trace_syscall_entry *entry;
- struct ltt_channel *chan = __data;
- struct ltt_event *event;
+ unsigned long args[UNKNOWN_SYSCALL_NRARGS];
- if (unlikely(id >= ARRAY_SIZE(sc_table)))
+ syscall_get_arguments(current, regs, 0, UNKNOWN_SYSCALL_NRARGS, args);
+ if (unlikely(is_compat_task()))
+ __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(is_compat_task())) {
+ struct lttng_syscall_filter *filter;
+
+ filter = 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 = 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;
- entry = &sc_table[id];
- if (unlikely(!entry->func))
+ }
+ if (unlikely(is_compat_task()))
+ event = chan->compat_sc_table[id];
+ else
+ event = chan->sc_table[id];
+ if (unlikely(!event)) {
+ syscall_entry_unknown(unknown_event, regs, id);
return;
- event = chan->sc_table[id];
- WARN_ON_ONCE(!event);
+ }
+ entry = &table[id];
+ WARN_ON_ONCE(!entry);
switch (entry->nrargs) {
case 0:
}
}
-static const struct lttng_event_desc *find_syscall_desc(unsigned int id)
+static void syscall_exit_unknown(struct lttng_event *event,
+ struct pt_regs *regs, int id, long ret)
{
- unsigned int i;
+ unsigned long args[UNKNOWN_SYSCALL_NRARGS];
- for (i = 0; i < __probe_desc___syscalls.nr_events; i++) {
- if (__probe_desc___syscalls.event_desc[i].fields
- == sc_table[id].fields)
- return &__probe_desc___syscalls.event_desc[i];
- }
- WARN_ON_ONCE(1);
- return NULL;
+ syscall_get_arguments(current, regs, 0, UNKNOWN_SYSCALL_NRARGS, args);
+ if (unlikely(is_compat_task()))
+ __event_probe__compat_syscall_exit_unknown(event, id, ret,
+ args);
+ else
+ __event_probe__syscall_exit_unknown(event, id, ret, args);
}
-static void fill_sc_table_desc(void)
+void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret)
{
- unsigned int i;
+ 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(is_compat_task())) {
+ struct lttng_syscall_filter *filter;
- if (sc_table_desc_filled)
+ filter = 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 = 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;
- /*
- * This is O(n^2), but rare. Eventually get the TRACE_EVENT code
- * to emit per-event symbols to skip this.
- */
- for (i = 0; i < ARRAY_SIZE(sc_table); i++) {
- const struct lttng_event_desc **desc = &sc_table[i].desc;
+ }
+ if (unlikely(is_compat_task()))
+ 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);
- if (!sc_table[i].func)
- continue;
- (*desc) = find_syscall_desc(i);
+ switch (entry->nrargs) {
+ case 0:
+ {
+ void (*fptr)(void *__data, long ret) = entry->func;
+
+ fptr(event, ret);
+ break;
}
- sc_table_desc_filled = 1;
-}
+ case 1:
+ {
+ void (*fptr)(void *__data,
+ long ret,
+ unsigned long arg0) = entry->func;
+ unsigned long args[1];
+ syscall_get_arguments(current, regs, 0, entry->nrargs, 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[2];
-int lttng_syscalls_register(struct ltt_channel *chan, void *filter)
-{
- unsigned int i;
- int ret;
+ syscall_get_arguments(current, regs, 0, entry->nrargs, 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[3];
- wrapper_vmalloc_sync_all();
- fill_sc_table_desc();
+ syscall_get_arguments(current, regs, 0, entry->nrargs, 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[4];
- if (!chan->sc_table) {
- /* create syscall table mapping syscall to events */
- chan->sc_table = kzalloc(sizeof(struct ltt_event *)
- * ARRAY_SIZE(sc_table), GFP_KERNEL);
- if (!chan->sc_table)
- return -ENOMEM;
+ syscall_get_arguments(current, regs, 0, entry->nrargs, 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[5];
+
+ syscall_get_arguments(current, regs, 0, entry->nrargs, 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[6];
+
+ syscall_get_arguments(current, regs, 0, entry->nrargs, 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 */
+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 < ARRAY_SIZE(sc_table); i++) {
+ for (i = 0; i < table_len; i++) {
struct lttng_kernel_event ev;
- const struct lttng_event_desc *desc = sc_table[i].desc;
+ desc = table[i].desc;
- if (!desc)
+ if (!desc) {
+ /* Unknown syscall */
continue;
+ }
/*
* Skip those already populated by previous failed
* register for this channel.
*/
- if (chan->sc_table[i])
+ if (chan_table[i])
continue;
memset(&ev, 0, sizeof(ev));
- strncpy(ev.name, desc->name, LTTNG_SYM_NAME_LEN);
- ev.name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ 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_NOOP;
- chan->sc_table[i] = ltt_event_create(chan, &ev, filter,
- desc);
- if (!chan->sc_table[i]) {
+ chan_table[i] = lttng_event_create(chan, &ev, filter,
+ desc);
+ 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 -EINVAL;
+ return PTR_ERR(chan_table[i]);
+ }
+ }
+ return 0;
+}
+
+int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
+{
+ struct lttng_kernel_event ev;
+ int ret;
+
+ wrapper_vmalloc_sync_all();
+
+ 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_NOOP;
+ chan->sc_unknown = lttng_event_create(chan, &ev, filter,
+ desc);
+ 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_NOOP;
+ chan->sc_compat_unknown = lttng_event_create(chan, &ev, filter,
+ desc);
+ 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_NOOP;
+ chan->compat_sc_exit_unknown = lttng_event_create(chan, &ev,
+ filter, desc);
+ WARN_ON_ONCE(!chan->compat_sc_exit_unknown);
+ if (IS_ERR(chan->compat_sc_exit_unknown)) {
+ return PTR_ERR(chan->compat_sc_exit_unknown);
}
}
- ret = tracepoint_probe_register("sys_enter",
- (void *) syscall_entry_probe, chan);
+
+ 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_NOOP;
+ chan->sc_exit_unknown = lttng_event_create(chan, &ev, filter,
+ desc);
+ 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 ltt_channel *chan)
+int lttng_syscalls_unregister(struct lttng_channel *chan)
{
int ret;
if (!chan->sc_table)
return 0;
- ret = tracepoint_probe_unregister("sys_enter",
- (void *) syscall_entry_probe, chan);
+ if (chan->sys_enter_registered) {
+ ret = lttng_wrapper_tracepoint_probe_unregister("sys_exit",
+ (void *) syscall_exit_probe, chan);
+ if (ret)
+ return ret;
+ chan->sys_enter_registered = 0;
+ }
+ if (chan->sys_exit_registered) {
+ ret = lttng_wrapper_tracepoint_probe_unregister("sys_enter",
+ (void *) syscall_entry_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;
- /* ltt_event destroy will be performed by ltt_session_destroy() */
- kfree(chan->sc_table);
+ 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++) {
+ bool 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++) {
+ bool 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);
+ if (file_fd < 0) {
+ ret = file_fd;
+ goto fd_error;
+ }
+ return file_fd;
+
+open_error:
+ fput(syscall_list_file);
+file_error:
+ put_unused_fd(file_fd);
+fd_error:
+ return ret;
+}