*/
#define pr_fmt(fmt) "trace_kprobe: " fmt
+#include <linux/bpf-cgroup.h>
+#include <linux/security.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/rculist.h>
#include <linux/error-injection.h>
+#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
+
#include "trace_dynevent.h"
#include "trace_kprobe_selftest.h"
#include "trace_probe.h"
#include "trace_probe_tmpl.h"
+#include "trace_probe_kernel.h"
#define KPROBE_EVENT_SYSTEM "kprobes"
#define KRETPROBE_MAXACTIVE_MAX 4096
-static int trace_kprobe_create(int argc, const char **argv);
+/* Kprobe early definition from command line */
+static char kprobe_boot_events_buf[COMMAND_LINE_SIZE] __initdata;
+
+static int __init set_kprobe_boot_events(char *str)
+{
+ strscpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE);
+ disable_tracing_selftest("running kprobe events");
+
+ return 1;
+}
+__setup("kprobe_event=", set_kprobe_boot_events);
+
+static int trace_kprobe_create(const char *raw_command);
static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev);
static int trace_kprobe_release(struct dyn_event *ev);
static bool trace_kprobe_is_busy(struct dyn_event *ev);
static bool trace_kprobe_match(const char *system, const char *event,
- struct dyn_event *ev);
+ int argc, const char **argv, struct dyn_event *ev);
static struct dyn_event_operations trace_kprobe_ops = {
.create = trace_kprobe_create,
for_each_dyn_event(dpos) \
if (is_trace_kprobe(dpos) && (pos = to_trace_kprobe(dpos)))
-#define SIZEOF_TRACE_KPROBE(n) \
- (offsetof(struct trace_kprobe, tp.args) + \
- (sizeof(struct probe_arg) * (n)))
-
static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk)
{
return tk->rp.handler != NULL;
static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk)
{
- return !!(kprobe_gone(&tk->rp.kp));
+ return kprobe_gone(&tk->rp.kp);
}
static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk,
struct module *mod)
{
- int len = strlen(mod->name);
+ int len = strlen(module_name(mod));
const char *name = trace_kprobe_symbol(tk);
- return strncmp(mod->name, name, len) == 0 && name[len] == ':';
+
+ return strncmp(module_name(mod), name, len) == 0 && name[len] == ':';
}
static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk)
if (!p)
return true;
*p = '\0';
- mutex_lock(&module_mutex);
+ rcu_read_lock_sched();
ret = !!find_module(tk->symbol);
- mutex_unlock(&module_mutex);
+ rcu_read_unlock_sched();
*p = ':';
return ret;
return trace_probe_is_enabled(&tk->tp);
}
+static bool trace_kprobe_match_command_head(struct trace_kprobe *tk,
+ int argc, const char **argv)
+{
+ char buf[MAX_ARGSTR_LEN + 1];
+
+ if (!argc)
+ return true;
+
+ if (!tk->symbol)
+ snprintf(buf, sizeof(buf), "0x%p", tk->rp.kp.addr);
+ else if (tk->rp.kp.offset)
+ snprintf(buf, sizeof(buf), "%s+%u",
+ trace_kprobe_symbol(tk), tk->rp.kp.offset);
+ else
+ snprintf(buf, sizeof(buf), "%s", trace_kprobe_symbol(tk));
+ if (strcmp(buf, argv[0]))
+ return false;
+ argc--; argv++;
+
+ return trace_probe_match_command_args(&tk->tp, argc, argv);
+}
+
static bool trace_kprobe_match(const char *system, const char *event,
- struct dyn_event *ev)
+ int argc, const char **argv, struct dyn_event *ev)
{
struct trace_kprobe *tk = to_trace_kprobe(ev);
- return strcmp(trace_event_name(&tk->tp.call), event) == 0 &&
- (!system || strcmp(tk->tp.call.class->system, system) == 0);
+ return (event[0] == '\0' ||
+ strcmp(trace_probe_name(&tk->tp), event) == 0) &&
+ (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 0) &&
+ trace_kprobe_match_command_head(tk, argc, argv);
}
static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
return nhit;
}
+static nokprobe_inline bool trace_kprobe_is_registered(struct trace_kprobe *tk)
+{
+ return !(list_empty(&tk->rp.kp.list) &&
+ hlist_unhashed(&tk->rp.kp.hlist));
+}
+
/* Return 0 if it fails to find the symbol address */
static nokprobe_inline
unsigned long trace_kprobe_address(struct trace_kprobe *tk)
return addr;
}
+static nokprobe_inline struct trace_kprobe *
+trace_kprobe_primary_from_call(struct trace_event_call *call)
+{
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return NULL;
+
+ return container_of(tp, struct trace_kprobe, tp);
+}
+
bool trace_kprobe_on_func_entry(struct trace_event_call *call)
{
- struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
+ struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
- return kprobe_on_func_entry(tk->rp.kp.addr,
+ return tk ? (kprobe_on_func_entry(tk->rp.kp.addr,
tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name,
- tk->rp.kp.addr ? 0 : tk->rp.kp.offset);
+ tk->rp.kp.addr ? 0 : tk->rp.kp.offset) == 0) : false;
}
bool trace_kprobe_error_injectable(struct trace_event_call *call)
{
- struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
+ struct trace_kprobe *tk = trace_kprobe_primary_from_call(call);
- return within_error_injection_list(trace_kprobe_address(tk));
+ return tk ? within_error_injection_list(trace_kprobe_address(tk)) :
+ false;
}
static int register_kprobe_event(struct trace_kprobe *tk);
static int kretprobe_dispatcher(struct kretprobe_instance *ri,
struct pt_regs *regs);
+static void free_trace_kprobe(struct trace_kprobe *tk)
+{
+ if (tk) {
+ trace_probe_cleanup(&tk->tp);
+ kfree(tk->symbol);
+ free_percpu(tk->nhit);
+ kfree(tk);
+ }
+}
+
/*
* Allocate new trace_probe and initialize it (including kprobes).
*/
struct trace_kprobe *tk;
int ret = -ENOMEM;
- tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL);
+ tk = kzalloc(struct_size(tk, tp.args, nargs), GFP_KERNEL);
if (!tk)
return ERR_PTR(ret);
tk->rp.kp.pre_handler = kprobe_dispatcher;
tk->rp.maxactive = maxactive;
+ INIT_HLIST_NODE(&tk->rp.kp.hlist);
+ INIT_LIST_HEAD(&tk->rp.kp.list);
- if (!event || !group) {
- ret = -EINVAL;
- goto error;
- }
-
- tk->tp.call.class = &tk->tp.class;
- tk->tp.call.name = kstrdup(event, GFP_KERNEL);
- if (!tk->tp.call.name)
- goto error;
-
- tk->tp.class.system = kstrdup(group, GFP_KERNEL);
- if (!tk->tp.class.system)
+ ret = trace_probe_init(&tk->tp, event, group, false, nargs);
+ if (ret < 0)
goto error;
dyn_event_init(&tk->devent, &trace_kprobe_ops);
- INIT_LIST_HEAD(&tk->tp.files);
return tk;
error:
- kfree(tk->tp.call.name);
- kfree(tk->symbol);
- free_percpu(tk->nhit);
- kfree(tk);
+ free_trace_kprobe(tk);
return ERR_PTR(ret);
}
-static void free_trace_kprobe(struct trace_kprobe *tk)
-{
- int i;
-
- if (!tk)
- return;
-
- for (i = 0; i < tk->tp.nr_args; i++)
- traceprobe_free_probe_arg(&tk->tp.args[i]);
-
- kfree(tk->tp.call.class->system);
- kfree(tk->tp.call.name);
- kfree(tk->symbol);
- free_percpu(tk->nhit);
- kfree(tk);
-}
-
static struct trace_kprobe *find_trace_kprobe(const char *event,
const char *group)
{
struct trace_kprobe *tk;
for_each_trace_kprobe(tk, pos)
- if (strcmp(trace_event_name(&tk->tp.call), event) == 0 &&
- strcmp(tk->tp.call.class->system, group) == 0)
+ if (strcmp(trace_probe_name(&tk->tp), event) == 0 &&
+ strcmp(trace_probe_group_name(&tk->tp), group) == 0)
return tk;
return NULL;
}
{
int ret = 0;
- if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) {
+ if (trace_kprobe_is_registered(tk) && !trace_kprobe_has_gone(tk)) {
if (trace_kprobe_is_return(tk))
ret = enable_kretprobe(&tk->rp);
else
return ret;
}
+static void __disable_trace_kprobe(struct trace_probe *tp)
+{
+ struct trace_kprobe *tk;
+
+ list_for_each_entry(tk, trace_probe_probe_list(tp), tp.list) {
+ if (!trace_kprobe_is_registered(tk))
+ continue;
+ if (trace_kprobe_is_return(tk))
+ disable_kretprobe(&tk->rp);
+ else
+ disable_kprobe(&tk->rp.kp);
+ }
+}
+
/*
* Enable trace_probe
* if the file is NULL, enable "perf" handler, or enable "trace" handler.
*/
-static int
-enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
+static int enable_trace_kprobe(struct trace_event_call *call,
+ struct trace_event_file *file)
{
- struct event_file_link *link;
+ struct trace_probe *tp;
+ struct trace_kprobe *tk;
+ bool enabled;
int ret = 0;
- if (file) {
- link = kmalloc(sizeof(*link), GFP_KERNEL);
- if (!link) {
- ret = -ENOMEM;
- goto out;
- }
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENODEV;
+ enabled = trace_probe_is_enabled(tp);
- link->file = file;
- list_add_tail_rcu(&link->list, &tk->tp.files);
+ /* This also changes "enabled" state */
+ if (file) {
+ ret = trace_probe_add_file(tp, file);
+ if (ret)
+ return ret;
+ } else
+ trace_probe_set_flag(tp, TP_FLAG_PROFILE);
- tk->tp.flags |= TP_FLAG_TRACE;
- ret = __enable_trace_kprobe(tk);
- if (ret) {
- list_del_rcu(&link->list);
- kfree(link);
- tk->tp.flags &= ~TP_FLAG_TRACE;
- }
+ if (enabled)
+ return 0;
- } else {
- tk->tp.flags |= TP_FLAG_PROFILE;
+ list_for_each_entry(tk, trace_probe_probe_list(tp), tp.list) {
+ if (trace_kprobe_has_gone(tk))
+ continue;
ret = __enable_trace_kprobe(tk);
if (ret)
- tk->tp.flags &= ~TP_FLAG_PROFILE;
+ break;
+ enabled = true;
}
- out:
+
+ if (ret) {
+ /* Failed to enable one of them. Roll back all */
+ if (enabled)
+ __disable_trace_kprobe(tp);
+ if (file)
+ trace_probe_remove_file(tp, file);
+ else
+ trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
+ }
+
return ret;
}
* Disable trace_probe
* if the file is NULL, disable "perf" handler, or disable "trace" handler.
*/
-static int
-disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
+static int disable_trace_kprobe(struct trace_event_call *call,
+ struct trace_event_file *file)
{
- struct event_file_link *link = NULL;
- int wait = 0;
- int ret = 0;
+ struct trace_probe *tp;
- if (file) {
- link = find_event_file_link(&tk->tp, file);
- if (!link) {
- ret = -EINVAL;
- goto out;
- }
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENODEV;
- list_del_rcu(&link->list);
- wait = 1;
- if (!list_empty(&tk->tp.files))
+ if (file) {
+ if (!trace_probe_get_file_link(tp, file))
+ return -ENOENT;
+ if (!trace_probe_has_single_file(tp))
goto out;
-
- tk->tp.flags &= ~TP_FLAG_TRACE;
+ trace_probe_clear_flag(tp, TP_FLAG_TRACE);
} else
- tk->tp.flags &= ~TP_FLAG_PROFILE;
+ trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
- if (!trace_probe_is_enabled(&tk->tp) && trace_probe_is_registered(&tk->tp)) {
- if (trace_kprobe_is_return(tk))
- disable_kretprobe(&tk->rp);
- else
- disable_kprobe(&tk->rp.kp);
- wait = 1;
- }
+ if (!trace_probe_is_enabled(tp))
+ __disable_trace_kprobe(tp);
- /*
- * if tk is not added to any list, it must be a local trace_kprobe
- * created with perf_event_open. We don't need to wait for these
- * trace_kprobes
- */
- if (list_empty(&tk->devent.list))
- wait = 0;
out:
- if (wait) {
+ if (file)
/*
- * Synchronize with kprobe_trace_func/kretprobe_trace_func
- * to ensure disabled (all running handlers are finished).
- * This is not only for kfree(), but also the caller,
- * trace_remove_event_call() supposes it for releasing
- * event_call related objects, which will be accessed in
- * the kprobe_trace_func/kretprobe_trace_func.
+ * Synchronization is done in below function. For perf event,
+ * file == NULL and perf_trace_event_unreg() calls
+ * tracepoint_synchronize_unregister() to ensure synchronize
+ * event. We don't need to care about it.
*/
- synchronize_rcu();
- kfree(link); /* Ignored if link == NULL */
- }
+ trace_probe_remove_file(tp, file);
- return ret;
+ return 0;
}
-#if defined(CONFIG_KPROBES_ON_FTRACE) && \
+#if defined(CONFIG_DYNAMIC_FTRACE) && \
!defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE)
-static bool within_notrace_func(struct trace_kprobe *tk)
+static bool __within_notrace_func(unsigned long addr)
{
- unsigned long offset, size, addr;
+ unsigned long offset, size;
- addr = trace_kprobe_address(tk);
if (!addr || !kallsyms_lookup_size_offset(addr, &size, &offset))
return false;
*/
return !ftrace_location_range(addr, addr + size - 1);
}
+
+static bool within_notrace_func(struct trace_kprobe *tk)
+{
+ unsigned long addr = trace_kprobe_address(tk);
+ char symname[KSYM_NAME_LEN], *p;
+
+ if (!__within_notrace_func(addr))
+ return false;
+
+ /* Check if the address is on a suffixed-symbol */
+ if (!lookup_symbol_name(addr, symname)) {
+ p = strchr(symname, '.');
+ if (!p)
+ return true;
+ *p = '\0';
+ addr = (unsigned long)kprobe_lookup_name(symname, 0);
+ if (addr)
+ return __within_notrace_func(addr);
+ }
+
+ return true;
+}
#else
#define within_notrace_func(tk) (false)
#endif
{
int i, ret;
- if (trace_probe_is_registered(&tk->tp))
+ ret = security_locked_down(LOCKDOWN_KPROBES);
+ if (ret)
+ return ret;
+
+ if (trace_kprobe_is_registered(tk))
return -EINVAL;
if (within_notrace_func(tk)) {
- pr_warn("Could not probe notrace function %s\n",
- trace_kprobe_symbol(tk));
+ pr_warn("Could not probe notrace function %ps\n",
+ (void *)trace_kprobe_address(tk));
return -EINVAL;
}
else
ret = register_kprobe(&tk->rp.kp);
- if (ret == 0)
- tk->tp.flags |= TP_FLAG_REGISTERED;
return ret;
}
/* Internal unregister function - just handle k*probes and flags */
static void __unregister_trace_kprobe(struct trace_kprobe *tk)
{
- if (trace_probe_is_registered(&tk->tp)) {
+ if (trace_kprobe_is_registered(tk)) {
if (trace_kprobe_is_return(tk))
unregister_kretprobe(&tk->rp);
else
unregister_kprobe(&tk->rp.kp);
- tk->tp.flags &= ~TP_FLAG_REGISTERED;
- /* Cleanup kprobe for reuse */
+ /* Cleanup kprobe for reuse and mark it unregistered */
+ INIT_HLIST_NODE(&tk->rp.kp.hlist);
+ INIT_LIST_HEAD(&tk->rp.kp.list);
if (tk->rp.kp.symbol_name)
tk->rp.kp.addr = NULL;
}
/* Unregister a trace_probe and probe_event */
static int unregister_trace_kprobe(struct trace_kprobe *tk)
{
+ /* If other probes are on the event, just unregister kprobe */
+ if (trace_probe_has_sibling(&tk->tp))
+ goto unreg;
+
/* Enabled event can not be unregistered */
if (trace_probe_is_enabled(&tk->tp))
return -EBUSY;
+ /* If there's a reference to the dynamic event */
+ if (trace_event_dyn_busy(trace_probe_event_call(&tk->tp)))
+ return -EBUSY;
+
/* Will fail if probe is being used by ftrace or perf */
if (unregister_kprobe_event(tk))
return -EBUSY;
+unreg:
__unregister_trace_kprobe(tk);
dyn_event_remove(&tk->devent);
+ trace_probe_unlink(&tk->tp);
return 0;
}
+static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig,
+ struct trace_kprobe *comp)
+{
+ struct trace_probe_event *tpe = orig->tp.event;
+ int i;
+
+ list_for_each_entry(orig, &tpe->probes, tp.list) {
+ if (strcmp(trace_kprobe_symbol(orig),
+ trace_kprobe_symbol(comp)) ||
+ trace_kprobe_offset(orig) != trace_kprobe_offset(comp))
+ continue;
+
+ /*
+ * trace_probe_compare_arg_type() ensured that nr_args and
+ * each argument name and type are same. Let's compare comm.
+ */
+ for (i = 0; i < orig->tp.nr_args; i++) {
+ if (strcmp(orig->tp.args[i].comm,
+ comp->tp.args[i].comm))
+ break;
+ }
+
+ if (i == orig->tp.nr_args)
+ return true;
+ }
+
+ return false;
+}
+
+static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to)
+{
+ int ret;
+
+ ret = trace_probe_compare_arg_type(&tk->tp, &to->tp);
+ if (ret) {
+ /* Note that argument starts index = 2 */
+ trace_probe_log_set_index(ret + 1);
+ trace_probe_log_err(0, DIFF_ARG_TYPE);
+ return -EEXIST;
+ }
+ if (trace_kprobe_has_same_kprobe(to, tk)) {
+ trace_probe_log_set_index(0);
+ trace_probe_log_err(0, SAME_PROBE);
+ return -EEXIST;
+ }
+
+ /* Append to existing event */
+ ret = trace_probe_append(&tk->tp, &to->tp);
+ if (ret)
+ return ret;
+
+ /* Register k*probe */
+ ret = __register_trace_kprobe(tk);
+ if (ret == -ENOENT && !trace_kprobe_module_exist(tk)) {
+ pr_warn("This probe might be able to register after target module is loaded. Continue.\n");
+ ret = 0;
+ }
+
+ if (ret)
+ trace_probe_unlink(&tk->tp);
+ else
+ dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp));
+
+ return ret;
+}
+
/* Register a trace_probe and probe_event */
static int register_trace_kprobe(struct trace_kprobe *tk)
{
mutex_lock(&event_mutex);
- /* Delete old (same name) event if exist */
- old_tk = find_trace_kprobe(trace_event_name(&tk->tp.call),
- tk->tp.call.class->system);
+ old_tk = find_trace_kprobe(trace_probe_name(&tk->tp),
+ trace_probe_group_name(&tk->tp));
if (old_tk) {
- ret = unregister_trace_kprobe(old_tk);
- if (ret < 0)
- goto end;
- free_trace_kprobe(old_tk);
+ if (trace_kprobe_is_return(tk) != trace_kprobe_is_return(old_tk)) {
+ trace_probe_log_set_index(0);
+ trace_probe_log_err(0, DIFF_PROBE_TYPE);
+ ret = -EEXIST;
+ } else {
+ ret = append_trace_kprobe(tk, old_tk);
+ }
+ goto end;
}
/* Register new event */
ret = register_kprobe_event(tk);
if (ret) {
- pr_warn("Failed to register probe event(%d)\n", ret);
+ if (ret == -EEXIST) {
+ trace_probe_log_set_index(0);
+ trace_probe_log_err(0, EVENT_EXIST);
+ } else
+ pr_warn("Failed to register probe event(%d)\n", ret);
goto end;
}
if (ret < 0)
unregister_kprobe_event(tk);
else
- dyn_event_add(&tk->devent);
+ dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp));
end:
mutex_unlock(&event_mutex);
ret = __register_trace_kprobe(tk);
if (ret)
pr_warn("Failed to re-register probe %s on %s: %d\n",
- trace_event_name(&tk->tp.call),
- mod->name, ret);
+ trace_probe_name(&tk->tp),
+ module_name(mod), ret);
}
}
mutex_unlock(&event_mutex);
.priority = 1 /* Invoked after kprobe module callback */
};
-/* Convert certain expected symbols into '_' when generating event names */
-static inline void sanitize_event_name(char *name)
+static int count_symbols(void *data, unsigned long unused)
+{
+ unsigned int *count = data;
+
+ (*count)++;
+
+ return 0;
+}
+
+struct sym_count_ctx {
+ unsigned int count;
+ const char *name;
+};
+
+static int count_mod_symbols(void *data, const char *name, unsigned long unused)
+{
+ struct sym_count_ctx *ctx = data;
+
+ if (strcmp(name, ctx->name) == 0)
+ ctx->count++;
+
+ return 0;
+}
+
+static unsigned int number_of_same_symbols(char *func_name)
{
- while (*name++ != '\0')
- if (*name == ':' || *name == '.')
- *name = '_';
+ struct sym_count_ctx ctx = { .count = 0, .name = func_name };
+
+ kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
+
+ module_kallsyms_on_each_symbol(NULL, count_mod_symbols, &ctx);
+
+ return ctx.count;
}
-static int trace_kprobe_create(int argc, const char *argv[])
+static int trace_kprobe_entry_handler(struct kretprobe_instance *ri,
+ struct pt_regs *regs);
+
+static int __trace_kprobe_create(int argc, const char *argv[])
{
/*
* Argument syntax:
* - Add kprobe:
- * p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
+ * p[:[GRP/][EVENT]] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
* - Add kretprobe:
- * r[MAXACTIVE][:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS]
+ * r[MAXACTIVE][:[GRP/][EVENT]] [MOD:]KSYM[+0] [FETCHARGS]
+ * Or
+ * p[:[GRP/][EVENT]] [MOD:]KSYM[+0]%return [FETCHARGS]
+ *
* Fetch args:
* $retval : fetch return value
* $stack : fetch stack address
* FETCHARG:TYPE : use TYPE instead of unsigned long.
*/
struct trace_kprobe *tk = NULL;
- int i, len, ret = 0;
+ int i, len, new_argc = 0, ret = 0;
bool is_return = false;
char *symbol = NULL, *tmp = NULL;
+ const char **new_argv = NULL;
const char *event = NULL, *group = KPROBE_EVENT_SYSTEM;
+ enum probe_print_type ptype;
int maxactive = 0;
long offset = 0;
void *addr = NULL;
char buf[MAX_EVENT_NAME_LEN];
- unsigned int flags = TPARG_FL_KERNEL;
+ char gbuf[MAX_EVENT_NAME_LEN];
+ char abuf[MAX_BTF_ARGS_LEN];
+ struct traceprobe_parse_context ctx = { .flags = TPARG_FL_KERNEL };
switch (argv[0][0]) {
case 'r':
is_return = true;
- flags |= TPARG_FL_RETURN;
break;
case 'p':
break;
if (isdigit(argv[0][1])) {
if (!is_return) {
- trace_probe_log_err(1, MAXACT_NO_KPROBE);
+ trace_probe_log_err(1, BAD_MAXACT_TYPE);
goto parse_error;
}
if (event)
symbol = kstrdup(argv[1], GFP_KERNEL);
if (!symbol)
return -ENOMEM;
+
+ tmp = strchr(symbol, '%');
+ if (tmp) {
+ if (!strcmp(tmp, "%return")) {
+ *tmp = '\0';
+ is_return = true;
+ } else {
+ trace_probe_log_err(tmp - symbol, BAD_ADDR_SUFFIX);
+ goto parse_error;
+ }
+ }
+
/* TODO: support .init module functions */
ret = traceprobe_split_symbol_offset(symbol, &offset);
if (ret || offset < 0 || offset > UINT_MAX) {
trace_probe_log_err(0, BAD_PROBE_ADDR);
goto parse_error;
}
- if (kprobe_on_func_entry(NULL, symbol, offset))
- flags |= TPARG_FL_FENTRY;
- if (offset && is_return && !(flags & TPARG_FL_FENTRY)) {
+ if (is_return)
+ ctx.flags |= TPARG_FL_RETURN;
+ ret = kprobe_on_func_entry(NULL, symbol, offset);
+ if (ret == 0 && !is_return)
+ ctx.flags |= TPARG_FL_FENTRY;
+ /* Defer the ENOENT case until register kprobe */
+ if (ret == -EINVAL && is_return) {
trace_probe_log_err(0, BAD_RETPROBE);
goto parse_error;
}
}
+ if (symbol && !strchr(symbol, ':')) {
+ unsigned int count;
+
+ count = number_of_same_symbols(symbol);
+ if (count > 1) {
+ /*
+ * Users should use ADDR to remove the ambiguity of
+ * using KSYM only.
+ */
+ trace_probe_log_err(0, NON_UNIQ_SYMBOL);
+ ret = -EADDRNOTAVAIL;
+
+ goto error;
+ } else if (count == 0) {
+ /*
+ * We can return ENOENT earlier than when register the
+ * kprobe.
+ */
+ trace_probe_log_err(0, BAD_PROBE_ADDR);
+ ret = -ENOENT;
+
+ goto error;
+ }
+ }
+
trace_probe_log_set_index(0);
if (event) {
- ret = traceprobe_parse_event_name(&event, &group, buf,
+ ret = traceprobe_parse_event_name(&event, &group, gbuf,
event - argv[0]);
if (ret)
goto parse_error;
- } else {
+ }
+
+ if (!event) {
/* Make a new event name */
if (symbol)
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
event = buf;
}
+ argc -= 2; argv += 2;
+ ctx.funcname = symbol;
+ new_argv = traceprobe_expand_meta_args(argc, argv, &new_argc,
+ abuf, MAX_BTF_ARGS_LEN, &ctx);
+ if (IS_ERR(new_argv)) {
+ ret = PTR_ERR(new_argv);
+ new_argv = NULL;
+ goto out;
+ }
+ if (new_argv) {
+ argc = new_argc;
+ argv = new_argv;
+ }
+
/* setup a probe */
tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive,
- argc - 2, is_return);
+ argc, is_return);
if (IS_ERR(tk)) {
ret = PTR_ERR(tk);
/* This must return -ENOMEM, else there is a bug */
WARN_ON_ONCE(ret != -ENOMEM);
goto out; /* We know tk is not allocated */
}
- argc -= 2; argv += 2;
/* parse arguments */
for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
- tmp = kstrdup(argv[i], GFP_KERNEL);
- if (!tmp) {
- ret = -ENOMEM;
- goto error;
- }
-
trace_probe_log_set_index(i + 2);
- ret = traceprobe_parse_probe_arg(&tk->tp, i, tmp, flags);
- kfree(tmp);
+ ctx.offset = 0;
+ ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], &ctx);
if (ret)
goto error; /* This can be -ENOMEM */
}
+ /* entry handler for kretprobe */
+ if (is_return && tk->tp.entry_arg) {
+ tk->rp.entry_handler = trace_kprobe_entry_handler;
+ tk->rp.data_size = traceprobe_get_entry_data_size(&tk->tp);
+ }
+
+ ptype = is_return ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
+ ret = traceprobe_set_print_fmt(&tk->tp, ptype);
+ if (ret < 0)
+ goto error;
ret = register_trace_kprobe(tk);
if (ret) {
trace_probe_log_err(0, BAD_INSN_BNDRY);
else if (ret == -ENOENT)
trace_probe_log_err(0, BAD_PROBE_ADDR);
- else if (ret != -ENOMEM)
+ else if (ret != -ENOMEM && ret != -EEXIST)
trace_probe_log_err(0, FAIL_REG_PROBE);
goto error;
}
out:
+ traceprobe_finish_parse(&ctx);
trace_probe_log_clear();
+ kfree(new_argv);
kfree(symbol);
return ret;
goto out;
}
-static int create_or_delete_trace_kprobe(int argc, char **argv)
+static int trace_kprobe_create(const char *raw_command)
+{
+ return trace_probe_create(raw_command, __trace_kprobe_create);
+}
+
+static int create_or_delete_trace_kprobe(const char *raw_command)
{
int ret;
- if (argv[0][0] == '-')
- return dyn_event_release(argc, argv, &trace_kprobe_ops);
+ if (raw_command[0] == '-')
+ return dyn_event_release(raw_command, &trace_kprobe_ops);
- ret = trace_kprobe_create(argc, (const char **)argv);
+ ret = trace_kprobe_create(raw_command);
return ret == -ECANCELED ? -EINVAL : ret;
}
+static int trace_kprobe_run_command(struct dynevent_cmd *cmd)
+{
+ return create_or_delete_trace_kprobe(cmd->seq.buffer);
+}
+
+/**
+ * kprobe_event_cmd_init - Initialize a kprobe event command object
+ * @cmd: A pointer to the dynevent_cmd struct representing the new event
+ * @buf: A pointer to the buffer used to build the command
+ * @maxlen: The length of the buffer passed in @buf
+ *
+ * Initialize a synthetic event command object. Use this before
+ * calling any of the other kprobe_event functions.
+ */
+void kprobe_event_cmd_init(struct dynevent_cmd *cmd, char *buf, int maxlen)
+{
+ dynevent_cmd_init(cmd, buf, maxlen, DYNEVENT_TYPE_KPROBE,
+ trace_kprobe_run_command);
+}
+EXPORT_SYMBOL_GPL(kprobe_event_cmd_init);
+
+/**
+ * __kprobe_event_gen_cmd_start - Generate a kprobe event command from arg list
+ * @cmd: A pointer to the dynevent_cmd struct representing the new event
+ * @kretprobe: Is this a return probe?
+ * @name: The name of the kprobe event
+ * @loc: The location of the kprobe event
+ * @...: Variable number of arg (pairs), one pair for each field
+ *
+ * NOTE: Users normally won't want to call this function directly, but
+ * rather use the kprobe_event_gen_cmd_start() wrapper, which automatically
+ * adds a NULL to the end of the arg list. If this function is used
+ * directly, make sure the last arg in the variable arg list is NULL.
+ *
+ * Generate a kprobe event command to be executed by
+ * kprobe_event_gen_cmd_end(). This function can be used to generate the
+ * complete command or only the first part of it; in the latter case,
+ * kprobe_event_add_fields() can be used to add more fields following this.
+ *
+ * Unlikely the synth_event_gen_cmd_start(), @loc must be specified. This
+ * returns -EINVAL if @loc == NULL.
+ *
+ * Return: 0 if successful, error otherwise.
+ */
+int __kprobe_event_gen_cmd_start(struct dynevent_cmd *cmd, bool kretprobe,
+ const char *name, const char *loc, ...)
+{
+ char buf[MAX_EVENT_NAME_LEN];
+ struct dynevent_arg arg;
+ va_list args;
+ int ret;
+
+ if (cmd->type != DYNEVENT_TYPE_KPROBE)
+ return -EINVAL;
+
+ if (!loc)
+ return -EINVAL;
+
+ if (kretprobe)
+ snprintf(buf, MAX_EVENT_NAME_LEN, "r:kprobes/%s", name);
+ else
+ snprintf(buf, MAX_EVENT_NAME_LEN, "p:kprobes/%s", name);
+
+ ret = dynevent_str_add(cmd, buf);
+ if (ret)
+ return ret;
+
+ dynevent_arg_init(&arg, 0);
+ arg.str = loc;
+ ret = dynevent_arg_add(cmd, &arg, NULL);
+ if (ret)
+ return ret;
+
+ va_start(args, loc);
+ for (;;) {
+ const char *field;
+
+ field = va_arg(args, const char *);
+ if (!field)
+ break;
+
+ if (++cmd->n_fields > MAX_TRACE_ARGS) {
+ ret = -EINVAL;
+ break;
+ }
+
+ arg.str = field;
+ ret = dynevent_arg_add(cmd, &arg, NULL);
+ if (ret)
+ break;
+ }
+ va_end(args);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__kprobe_event_gen_cmd_start);
+
+/**
+ * __kprobe_event_add_fields - Add probe fields to a kprobe command from arg list
+ * @cmd: A pointer to the dynevent_cmd struct representing the new event
+ * @...: Variable number of arg (pairs), one pair for each field
+ *
+ * NOTE: Users normally won't want to call this function directly, but
+ * rather use the kprobe_event_add_fields() wrapper, which
+ * automatically adds a NULL to the end of the arg list. If this
+ * function is used directly, make sure the last arg in the variable
+ * arg list is NULL.
+ *
+ * Add probe fields to an existing kprobe command using a variable
+ * list of args. Fields are added in the same order they're listed.
+ *
+ * Return: 0 if successful, error otherwise.
+ */
+int __kprobe_event_add_fields(struct dynevent_cmd *cmd, ...)
+{
+ struct dynevent_arg arg;
+ va_list args;
+ int ret = 0;
+
+ if (cmd->type != DYNEVENT_TYPE_KPROBE)
+ return -EINVAL;
+
+ dynevent_arg_init(&arg, 0);
+
+ va_start(args, cmd);
+ for (;;) {
+ const char *field;
+
+ field = va_arg(args, const char *);
+ if (!field)
+ break;
+
+ if (++cmd->n_fields > MAX_TRACE_ARGS) {
+ ret = -EINVAL;
+ break;
+ }
+
+ arg.str = field;
+ ret = dynevent_arg_add(cmd, &arg, NULL);
+ if (ret)
+ break;
+ }
+ va_end(args);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__kprobe_event_add_fields);
+
+/**
+ * kprobe_event_delete - Delete a kprobe event
+ * @name: The name of the kprobe event to delete
+ *
+ * Delete a kprobe event with the give @name from kernel code rather
+ * than directly from the command line.
+ *
+ * Return: 0 if successful, error otherwise.
+ */
+int kprobe_event_delete(const char *name)
+{
+ char buf[MAX_EVENT_NAME_LEN];
+
+ snprintf(buf, MAX_EVENT_NAME_LEN, "-:%s", name);
+
+ return create_or_delete_trace_kprobe(buf);
+}
+EXPORT_SYMBOL_GPL(kprobe_event_delete);
+
static int trace_kprobe_release(struct dyn_event *ev)
{
struct trace_kprobe *tk = to_trace_kprobe(ev);
int i;
seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p');
- seq_printf(m, ":%s/%s", tk->tp.call.class->system,
- trace_event_name(&tk->tp.call));
+ if (trace_kprobe_is_return(tk) && tk->rp.maxactive)
+ seq_printf(m, "%d", tk->rp.maxactive);
+ seq_printf(m, ":%s/%s", trace_probe_group_name(&tk->tp),
+ trace_probe_name(&tk->tp));
if (!tk->symbol)
seq_printf(m, " 0x%p", tk->rp.kp.addr);
{
int ret;
+ ret = security_locked_down(LOCKDOWN_TRACEFS);
+ if (ret)
+ return ret;
+
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
ret = dyn_events_release_all(&trace_kprobe_ops);
if (ret < 0)
.write = probes_write,
};
+static unsigned long trace_kprobe_missed(struct trace_kprobe *tk)
+{
+ return trace_kprobe_is_return(tk) ?
+ tk->rp.kp.nmissed + tk->rp.nmissed : tk->rp.kp.nmissed;
+}
+
/* Probes profiling interfaces */
static int probes_profile_seq_show(struct seq_file *m, void *v)
{
struct dyn_event *ev = v;
struct trace_kprobe *tk;
+ unsigned long nmissed;
if (!is_trace_kprobe(ev))
return 0;
tk = to_trace_kprobe(ev);
+ nmissed = trace_kprobe_missed(tk);
seq_printf(m, " %-44s %15lu %15lu\n",
- trace_event_name(&tk->tp.call),
+ trace_probe_name(&tk->tp),
trace_kprobe_nhit(tk),
- tk->rp.kp.nmissed);
+ nmissed);
return 0;
}
static int profile_open(struct inode *inode, struct file *file)
{
+ int ret;
+
+ ret = security_locked_down(LOCKDOWN_TRACEFS);
+ if (ret)
+ return ret;
+
return seq_open(file, &profile_seq_op);
}
.release = seq_release,
};
-/* Kprobe specific fetch functions */
-
-/* Return the length of string -- including null terminal byte */
-static nokprobe_inline int
-fetch_store_strlen(unsigned long addr)
-{
- int ret, len = 0;
- u8 c;
-
- do {
- ret = probe_kernel_read(&c, (u8 *)addr + len, 1);
- len++;
- } while (c && ret == 0 && len < MAX_STRING_SIZE);
-
- return (ret < 0) ? ret : len;
-}
-
-/*
- * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
- * length and relative data location.
- */
-static nokprobe_inline int
-fetch_store_string(unsigned long addr, void *dest, void *base)
-{
- int maxlen = get_loc_len(*(u32 *)dest);
- u8 *dst = get_loc_data(dest, base);
- long ret;
-
- if (unlikely(!maxlen))
- return -ENOMEM;
- /*
- * Try to get string again, since the string can be changed while
- * probing.
- */
- ret = strncpy_from_unsafe(dst, (void *)addr, maxlen);
-
- if (ret >= 0)
- *(u32 *)dest = make_data_loc(ret, (void *)dst - base);
- return ret;
-}
-
-static nokprobe_inline int
-probe_mem_read(void *dest, void *src, size_t size)
-{
- return probe_kernel_read(dest, src, size);
-}
-
/* Note that we don't verify it, since the code does not come from user space */
static int
-process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
- void *base)
+process_fetch_insn(struct fetch_insn *code, void *rec, void *edata,
+ void *dest, void *base)
{
+ struct pt_regs *regs = rec;
unsigned long val;
+ int ret;
retry:
/* 1st stage: get value from context */
case FETCH_OP_RETVAL:
val = regs_return_value(regs);
break;
- case FETCH_OP_IMM:
- val = code->immediate;
- break;
- case FETCH_OP_COMM:
- val = (unsigned long)current->comm;
- break;
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
case FETCH_OP_ARG:
val = regs_get_kernel_argument(regs, code->param);
break;
+ case FETCH_OP_EDATA:
+ val = *(unsigned long *)((unsigned long)edata + code->offset);
+ break;
#endif
case FETCH_NOP_SYMBOL: /* Ignore a place holder */
code++;
goto retry;
default:
- return -EILSEQ;
+ ret = process_common_fetch_insn(code, &val);
+ if (ret < 0)
+ return ret;
}
code++;
struct trace_event_file *trace_file)
{
struct kprobe_trace_entry_head *entry;
- struct ring_buffer_event *event;
- struct ring_buffer *buffer;
- int size, dsize, pc;
- unsigned long irq_flags;
- struct trace_event_call *call = &tk->tp.call;
+ struct trace_event_call *call = trace_probe_event_call(&tk->tp);
+ struct trace_event_buffer fbuffer;
+ int dsize;
WARN_ON(call != trace_file->event_call);
if (trace_trigger_soft_disabled(trace_file))
return;
- local_save_flags(irq_flags);
- pc = preempt_count();
-
- dsize = __get_data_size(&tk->tp, regs);
- size = sizeof(*entry) + tk->tp.size + dsize;
+ dsize = __get_data_size(&tk->tp, regs, NULL);
- event = trace_event_buffer_lock_reserve(&buffer, trace_file,
- call->event.type,
- size, irq_flags, pc);
- if (!event)
+ entry = trace_event_buffer_reserve(&fbuffer, trace_file,
+ sizeof(*entry) + tk->tp.size + dsize);
+ if (!entry)
return;
- entry = ring_buffer_event_data(event);
+ fbuffer.regs = regs;
entry->ip = (unsigned long)tk->rp.kp.addr;
- store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
+ store_trace_args(&entry[1], &tk->tp, regs, NULL, sizeof(*entry), dsize);
- event_trigger_unlock_commit_regs(trace_file, buffer, event,
- entry, irq_flags, pc, regs);
+ trace_event_buffer_commit(&fbuffer);
}
static void
{
struct event_file_link *link;
- list_for_each_entry_rcu(link, &tk->tp.files, list)
+ trace_probe_for_each_link_rcu(link, &tk->tp)
__kprobe_trace_func(tk, regs, link->file);
}
NOKPROBE_SYMBOL(kprobe_trace_func);
/* Kretprobe handler */
+
+static int trace_kprobe_entry_handler(struct kretprobe_instance *ri,
+ struct pt_regs *regs)
+{
+ struct kretprobe *rp = get_kretprobe(ri);
+ struct trace_kprobe *tk;
+
+ /*
+ * There is a small chance that get_kretprobe(ri) returns NULL when
+ * the kretprobe is unregister on another CPU between kretprobe's
+ * trampoline_handler and this function.
+ */
+ if (unlikely(!rp))
+ return -ENOENT;
+
+ tk = container_of(rp, struct trace_kprobe, rp);
+
+ /* store argument values into ri->data as entry data */
+ if (tk->tp.entry_arg)
+ store_trace_entry_data(ri->data, &tk->tp, regs);
+
+ return 0;
+}
+
+
static nokprobe_inline void
__kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
struct pt_regs *regs,
struct trace_event_file *trace_file)
{
struct kretprobe_trace_entry_head *entry;
- struct ring_buffer_event *event;
- struct ring_buffer *buffer;
- int size, pc, dsize;
- unsigned long irq_flags;
- struct trace_event_call *call = &tk->tp.call;
+ struct trace_event_buffer fbuffer;
+ struct trace_event_call *call = trace_probe_event_call(&tk->tp);
+ int dsize;
WARN_ON(call != trace_file->event_call);
if (trace_trigger_soft_disabled(trace_file))
return;
- local_save_flags(irq_flags);
- pc = preempt_count();
-
- dsize = __get_data_size(&tk->tp, regs);
- size = sizeof(*entry) + tk->tp.size + dsize;
+ dsize = __get_data_size(&tk->tp, regs, ri->data);
- event = trace_event_buffer_lock_reserve(&buffer, trace_file,
- call->event.type,
- size, irq_flags, pc);
- if (!event)
+ entry = trace_event_buffer_reserve(&fbuffer, trace_file,
+ sizeof(*entry) + tk->tp.size + dsize);
+ if (!entry)
return;
- entry = ring_buffer_event_data(event);
+ fbuffer.regs = regs;
entry->func = (unsigned long)tk->rp.kp.addr;
- entry->ret_ip = (unsigned long)ri->ret_addr;
- store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
+ entry->ret_ip = get_kretprobe_retaddr(ri);
+ store_trace_args(&entry[1], &tk->tp, regs, ri->data, sizeof(*entry), dsize);
- event_trigger_unlock_commit_regs(trace_file, buffer, event,
- entry, irq_flags, pc, regs);
+ trace_event_buffer_commit(&fbuffer);
}
static void
{
struct event_file_link *link;
- list_for_each_entry_rcu(link, &tk->tp.files, list)
+ trace_probe_for_each_link_rcu(link, &tk->tp)
__kretprobe_trace_func(tk, ri, regs, link->file);
}
NOKPROBE_SYMBOL(kretprobe_trace_func);
struct trace_probe *tp;
field = (struct kprobe_trace_entry_head *)iter->ent;
- tp = container_of(event, struct trace_probe, call.event);
+ tp = trace_probe_primary_from_call(
+ container_of(event, struct trace_event_call, event));
+ if (WARN_ON_ONCE(!tp))
+ goto out;
- trace_seq_printf(s, "%s: (", trace_event_name(&tp->call));
+ trace_seq_printf(s, "%s: (", trace_probe_name(tp));
if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
goto out;
trace_seq_putc(s, ')');
- if (print_probe_args(s, tp->args, tp->nr_args,
+ if (trace_probe_print_args(s, tp->args, tp->nr_args,
(u8 *)&field[1], field) < 0)
goto out;
struct trace_probe *tp;
field = (struct kretprobe_trace_entry_head *)iter->ent;
- tp = container_of(event, struct trace_probe, call.event);
+ tp = trace_probe_primary_from_call(
+ container_of(event, struct trace_event_call, event));
+ if (WARN_ON_ONCE(!tp))
+ goto out;
- trace_seq_printf(s, "%s: (", trace_event_name(&tp->call));
+ trace_seq_printf(s, "%s: (", trace_probe_name(tp));
if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
goto out;
trace_seq_putc(s, ')');
- if (print_probe_args(s, tp->args, tp->nr_args,
+ if (trace_probe_print_args(s, tp->args, tp->nr_args,
(u8 *)&field[1], field) < 0)
goto out;
{
int ret;
struct kprobe_trace_entry_head field;
- struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data;
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(event_call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENOENT;
DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
- return traceprobe_define_arg_fields(event_call, sizeof(field), &tk->tp);
+ return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
}
static int kretprobe_event_define_fields(struct trace_event_call *event_call)
{
int ret;
struct kretprobe_trace_entry_head field;
- struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data;
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(event_call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENOENT;
DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
- return traceprobe_define_arg_fields(event_call, sizeof(field), &tk->tp);
+ return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
}
#ifdef CONFIG_PERF_EVENTS
static int
kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
{
- struct trace_event_call *call = &tk->tp.call;
+ struct trace_event_call *call = trace_probe_event_call(&tk->tp);
struct kprobe_trace_entry_head *entry;
struct hlist_head *head;
int size, __size, dsize;
if (hlist_empty(head))
return 0;
- dsize = __get_data_size(&tk->tp, regs);
+ dsize = __get_data_size(&tk->tp, regs, NULL);
__size = sizeof(*entry) + tk->tp.size + dsize;
size = ALIGN(__size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
entry->ip = (unsigned long)tk->rp.kp.addr;
memset(&entry[1], 0, dsize);
- store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
+ store_trace_args(&entry[1], &tk->tp, regs, NULL, sizeof(*entry), dsize);
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
head, NULL);
return 0;
kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
struct pt_regs *regs)
{
- struct trace_event_call *call = &tk->tp.call;
+ struct trace_event_call *call = trace_probe_event_call(&tk->tp);
struct kretprobe_trace_entry_head *entry;
struct hlist_head *head;
int size, __size, dsize;
if (hlist_empty(head))
return;
- dsize = __get_data_size(&tk->tp, regs);
+ dsize = __get_data_size(&tk->tp, regs, ri->data);
__size = sizeof(*entry) + tk->tp.size + dsize;
size = ALIGN(__size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
return;
entry->func = (unsigned long)tk->rp.kp.addr;
- entry->ret_ip = (unsigned long)ri->ret_addr;
- store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
+ entry->ret_ip = get_kretprobe_retaddr(ri);
+ store_trace_args(&entry[1], &tk->tp, regs, ri->data, sizeof(*entry), dsize);
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
head, NULL);
}
int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type,
const char **symbol, u64 *probe_offset,
- u64 *probe_addr, bool perf_type_tracepoint)
+ u64 *probe_addr, unsigned long *missed,
+ bool perf_type_tracepoint)
{
const char *pevent = trace_event_name(event->tp_event);
const char *group = event->tp_event->class->system;
if (perf_type_tracepoint)
tk = find_trace_kprobe(pevent, group);
else
- tk = event->tp_event->data;
+ tk = trace_kprobe_primary_from_call(event->tp_event);
if (!tk)
return -EINVAL;
*fd_type = trace_kprobe_is_return(tk) ? BPF_FD_TYPE_KRETPROBE
: BPF_FD_TYPE_KPROBE;
- if (tk->symbol) {
- *symbol = tk->symbol;
- *probe_offset = tk->rp.kp.offset;
- *probe_addr = 0;
- } else {
- *symbol = NULL;
- *probe_offset = 0;
- *probe_addr = (unsigned long)tk->rp.kp.addr;
- }
+ *probe_offset = tk->rp.kp.offset;
+ *probe_addr = kallsyms_show_value(current_cred()) ?
+ (unsigned long)tk->rp.kp.addr : 0;
+ *symbol = tk->symbol;
+ if (missed)
+ *missed = trace_kprobe_missed(tk);
return 0;
}
#endif /* CONFIG_PERF_EVENTS */
static int kprobe_register(struct trace_event_call *event,
enum trace_reg type, void *data)
{
- struct trace_kprobe *tk = (struct trace_kprobe *)event->data;
struct trace_event_file *file = data;
switch (type) {
case TRACE_REG_REGISTER:
- return enable_trace_kprobe(tk, file);
+ return enable_trace_kprobe(event, file);
case TRACE_REG_UNREGISTER:
- return disable_trace_kprobe(tk, file);
+ return disable_trace_kprobe(event, file);
#ifdef CONFIG_PERF_EVENTS
case TRACE_REG_PERF_REGISTER:
- return enable_trace_kprobe(tk, NULL);
+ return enable_trace_kprobe(event, NULL);
case TRACE_REG_PERF_UNREGISTER:
- return disable_trace_kprobe(tk, NULL);
+ return disable_trace_kprobe(event, NULL);
case TRACE_REG_PERF_OPEN:
case TRACE_REG_PERF_CLOSE:
case TRACE_REG_PERF_ADD:
raw_cpu_inc(*tk->nhit);
- if (tk->tp.flags & TP_FLAG_TRACE)
+ if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE))
kprobe_trace_func(tk, regs);
#ifdef CONFIG_PERF_EVENTS
- if (tk->tp.flags & TP_FLAG_PROFILE)
+ if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE))
ret = kprobe_perf_func(tk, regs);
#endif
return ret;
static int
kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
{
- struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp);
+ struct kretprobe *rp = get_kretprobe(ri);
+ struct trace_kprobe *tk;
+
+ /*
+ * There is a small chance that get_kretprobe(ri) returns NULL when
+ * the kretprobe is unregister on another CPU between kretprobe's
+ * trampoline_handler and this function.
+ */
+ if (unlikely(!rp))
+ return 0;
+ tk = container_of(rp, struct trace_kprobe, rp);
raw_cpu_inc(*tk->nhit);
- if (tk->tp.flags & TP_FLAG_TRACE)
+ if (trace_probe_test_flag(&tk->tp, TP_FLAG_TRACE))
kretprobe_trace_func(tk, ri, regs);
#ifdef CONFIG_PERF_EVENTS
- if (tk->tp.flags & TP_FLAG_PROFILE)
+ if (trace_probe_test_flag(&tk->tp, TP_FLAG_PROFILE))
kretprobe_perf_func(tk, ri, regs);
#endif
- return 0; /* We don't tweek kernel, so just return 0 */
+ return 0; /* We don't tweak kernel, so just return 0 */
}
NOKPROBE_SYMBOL(kretprobe_dispatcher);
.trace = print_kprobe_event
};
-static inline void init_trace_event_call(struct trace_kprobe *tk,
- struct trace_event_call *call)
+static struct trace_event_fields kretprobe_fields_array[] = {
+ { .type = TRACE_FUNCTION_TYPE,
+ .define_fields = kretprobe_event_define_fields },
+ {}
+};
+
+static struct trace_event_fields kprobe_fields_array[] = {
+ { .type = TRACE_FUNCTION_TYPE,
+ .define_fields = kprobe_event_define_fields },
+ {}
+};
+
+static inline void init_trace_event_call(struct trace_kprobe *tk)
{
- INIT_LIST_HEAD(&call->class->fields);
+ struct trace_event_call *call = trace_probe_event_call(&tk->tp);
+
if (trace_kprobe_is_return(tk)) {
call->event.funcs = &kretprobe_funcs;
- call->class->define_fields = kretprobe_event_define_fields;
+ call->class->fields_array = kretprobe_fields_array;
} else {
call->event.funcs = &kprobe_funcs;
- call->class->define_fields = kprobe_event_define_fields;
+ call->class->fields_array = kprobe_fields_array;
}
call->flags = TRACE_EVENT_FL_KPROBE;
call->class->reg = kprobe_register;
- call->data = tk;
}
static int register_kprobe_event(struct trace_kprobe *tk)
{
- struct trace_event_call *call = &tk->tp.call;
- int ret = 0;
+ init_trace_event_call(tk);
- init_trace_event_call(tk, call);
-
- if (traceprobe_set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0)
- return -ENOMEM;
- ret = register_trace_event(&call->event);
- if (!ret) {
- kfree(call->print_fmt);
- return -ENODEV;
- }
- ret = trace_add_event_call(call);
- if (ret) {
- pr_info("Failed to register kprobe event: %s\n",
- trace_event_name(call));
- kfree(call->print_fmt);
- unregister_trace_event(&call->event);
- }
- return ret;
+ return trace_probe_register_event_call(&tk->tp);
}
static int unregister_kprobe_event(struct trace_kprobe *tk)
{
- int ret;
-
- /* tp->event is unregistered in trace_remove_event_call() */
- ret = trace_remove_event_call(&tk->tp.call);
- if (!ret)
- kfree(tk->tp.call.print_fmt);
- return ret;
+ return trace_probe_unregister_event_call(&tk->tp);
}
#ifdef CONFIG_PERF_EVENTS
+
/* create a trace_kprobe, but don't add it to global lists */
struct trace_event_call *
create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
bool is_return)
{
+ enum probe_print_type ptype;
struct trace_kprobe *tk;
int ret;
char *event;
+ if (func) {
+ unsigned int count;
+
+ count = number_of_same_symbols(func);
+ if (count > 1)
+ /*
+ * Users should use addr to remove the ambiguity of
+ * using func only.
+ */
+ return ERR_PTR(-EADDRNOTAVAIL);
+ else if (count == 0)
+ /*
+ * We can return ENOENT earlier than when register the
+ * kprobe.
+ */
+ return ERR_PTR(-ENOENT);
+ }
+
/*
* local trace_kprobes are not added to dyn_event, so they are never
* searched in find_trace_kprobe(). Therefore, there is no concern of
return ERR_CAST(tk);
}
- init_trace_event_call(tk, &tk->tp.call);
+ init_trace_event_call(tk);
- if (traceprobe_set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) {
+ ptype = trace_kprobe_is_return(tk) ?
+ PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
+ if (traceprobe_set_print_fmt(&tk->tp, ptype) < 0) {
ret = -ENOMEM;
goto error;
}
ret = __register_trace_kprobe(tk);
- if (ret < 0) {
- kfree(tk->tp.call.print_fmt);
+ if (ret < 0)
goto error;
- }
- return &tk->tp.call;
+ return trace_probe_event_call(&tk->tp);
error:
free_trace_kprobe(tk);
return ERR_PTR(ret);
{
struct trace_kprobe *tk;
- tk = container_of(event_call, struct trace_kprobe, tp.call);
+ tk = trace_kprobe_primary_from_call(event_call);
+ if (unlikely(!tk))
+ return;
if (trace_probe_is_enabled(&tk->tp)) {
WARN_ON(1);
__unregister_trace_kprobe(tk);
- kfree(tk->tp.call.print_fmt);
free_trace_kprobe(tk);
}
#endif /* CONFIG_PERF_EVENTS */
-/* Make a tracefs interface for controlling probe points */
-static __init int init_kprobe_trace(void)
+static __init void enable_boot_kprobe_events(void)
+{
+ struct trace_array *tr = top_trace_array();
+ struct trace_event_file *file;
+ struct trace_kprobe *tk;
+ struct dyn_event *pos;
+
+ mutex_lock(&event_mutex);
+ for_each_trace_kprobe(tk, pos) {
+ list_for_each_entry(file, &tr->events, list)
+ if (file->event_call == trace_probe_event_call(&tk->tp))
+ trace_event_enable_disable(file, 1, 0);
+ }
+ mutex_unlock(&event_mutex);
+}
+
+static __init void setup_boot_kprobe_events(void)
+{
+ char *p, *cmd = kprobe_boot_events_buf;
+ int ret;
+
+ strreplace(kprobe_boot_events_buf, ',', ' ');
+
+ while (cmd && *cmd != '\0') {
+ p = strchr(cmd, ';');
+ if (p)
+ *p++ = '\0';
+
+ ret = create_or_delete_trace_kprobe(cmd);
+ if (ret)
+ pr_warn("Failed to add event(%d): %s\n", ret, cmd);
+
+ cmd = p;
+ }
+
+ enable_boot_kprobe_events();
+}
+
+/*
+ * Register dynevent at core_initcall. This allows kernel to setup kprobe
+ * events in postcore_initcall without tracefs.
+ */
+static __init int init_kprobe_trace_early(void)
{
- struct dentry *d_tracer;
- struct dentry *entry;
int ret;
ret = dyn_event_register(&trace_kprobe_ops);
if (register_module_notifier(&trace_kprobe_module_nb))
return -EINVAL;
- d_tracer = tracing_init_dentry();
- if (IS_ERR(d_tracer))
- return 0;
+ return 0;
+}
+core_initcall(init_kprobe_trace_early);
- entry = tracefs_create_file("kprobe_events", 0644, d_tracer,
- NULL, &kprobe_events_ops);
+/* Make a tracefs interface for controlling probe points */
+static __init int init_kprobe_trace(void)
+{
+ int ret;
+
+ ret = tracing_init_dentry();
+ if (ret)
+ return 0;
/* Event list interface */
- if (!entry)
- pr_warn("Could not create tracefs 'kprobe_events' entry\n");
+ trace_create_file("kprobe_events", TRACE_MODE_WRITE,
+ NULL, NULL, &kprobe_events_ops);
/* Profile interface */
- entry = tracefs_create_file("kprobe_profile", 0444, d_tracer,
- NULL, &kprobe_profile_ops);
+ trace_create_file("kprobe_profile", TRACE_MODE_READ,
+ NULL, NULL, &kprobe_profile_ops);
+
+ setup_boot_kprobe_events();
- if (!entry)
- pr_warn("Could not create tracefs 'kprobe_profile' entry\n");
return 0;
}
fs_initcall(init_kprobe_trace);
struct trace_event_file *file;
list_for_each_entry(file, &tr->events, list)
- if (file->event_call == &tk->tp.call)
+ if (file->event_call == trace_probe_event_call(&tk->tp))
return file;
return NULL;
if (tracing_is_disabled())
return -ENODEV;
+ if (tracing_selftest_disabled)
+ return 0;
+
target = kprobe_trace_selftest_target;
pr_info("Testing kprobe tracing: ");
- ret = trace_run_command("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)",
- create_or_delete_trace_kprobe);
+ ret = create_or_delete_trace_kprobe("p:testprobe kprobe_trace_selftest_target $stack $stack0 +0($stack)");
if (WARN_ON_ONCE(ret)) {
pr_warn("error on probing function entry.\n");
warn++;
pr_warn("error on getting probe file.\n");
warn++;
} else
- enable_trace_kprobe(tk, file);
+ enable_trace_kprobe(
+ trace_probe_event_call(&tk->tp), file);
}
}
- ret = trace_run_command("r:testprobe2 kprobe_trace_selftest_target $retval",
- create_or_delete_trace_kprobe);
+ ret = create_or_delete_trace_kprobe("r:testprobe2 kprobe_trace_selftest_target $retval");
if (WARN_ON_ONCE(ret)) {
pr_warn("error on probing function return.\n");
warn++;
pr_warn("error on getting probe file.\n");
warn++;
} else
- enable_trace_kprobe(tk, file);
+ enable_trace_kprobe(
+ trace_probe_event_call(&tk->tp), file);
}
}
pr_warn("error on getting probe file.\n");
warn++;
} else
- disable_trace_kprobe(tk, file);
+ disable_trace_kprobe(
+ trace_probe_event_call(&tk->tp), file);
}
tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM);
pr_warn("error on getting probe file.\n");
warn++;
} else
- disable_trace_kprobe(tk, file);
+ disable_trace_kprobe(
+ trace_probe_event_call(&tk->tp), file);
}
- ret = trace_run_command("-:testprobe", create_or_delete_trace_kprobe);
+ ret = create_or_delete_trace_kprobe("-:testprobe");
if (WARN_ON_ONCE(ret)) {
pr_warn("error on deleting a probe.\n");
warn++;
}
- ret = trace_run_command("-:testprobe2", create_or_delete_trace_kprobe);
+ ret = create_or_delete_trace_kprobe("-:testprobe2");
if (WARN_ON_ONCE(ret)) {
pr_warn("error on deleting a probe.\n");
warn++;