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Diffstat (limited to 'kernel/trace/trace_kprobe.c')
-rw-r--r--kernel/trace/trace_kprobe.c268
1 files changed, 218 insertions, 50 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 9d483ad9bb6c..a6697e28ddda 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -39,7 +39,7 @@ 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,
@@ -137,13 +137,36 @@ static bool trace_kprobe_is_busy(struct dyn_event *ev)
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_probe_name(&tk->tp), event) == 0 &&
- (!system || strcmp(trace_probe_group_name(&tk->tp), system) == 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)
@@ -180,20 +203,33 @@ 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) : 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);
@@ -291,32 +327,68 @@ static inline int __enable_trace_kprobe(struct trace_kprobe *tk)
return ret;
}
+static void __disable_trace_kprobe(struct trace_probe *tp)
+{
+ struct trace_probe *pos;
+ struct trace_kprobe *tk;
+
+ list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+ tk = container_of(pos, struct trace_kprobe, tp);
+ 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)
{
- bool enabled = trace_probe_is_enabled(&tk->tp);
+ struct trace_probe *pos, *tp;
+ struct trace_kprobe *tk;
+ bool enabled;
int ret = 0;
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENODEV;
+ enabled = trace_probe_is_enabled(tp);
+
+ /* This also changes "enabled" state */
if (file) {
- ret = trace_probe_add_file(&tk->tp, file);
+ ret = trace_probe_add_file(tp, file);
if (ret)
return ret;
} else
- trace_probe_set_flag(&tk->tp, TP_FLAG_PROFILE);
+ trace_probe_set_flag(tp, TP_FLAG_PROFILE);
if (enabled)
return 0;
- ret = __enable_trace_kprobe(tk);
+ list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+ tk = container_of(pos, struct trace_kprobe, tp);
+ if (trace_kprobe_has_gone(tk))
+ continue;
+ ret = __enable_trace_kprobe(tk);
+ if (ret)
+ break;
+ enabled = true;
+ }
+
if (ret) {
+ /* Failed to enable one of them. Roll back all */
+ if (enabled)
+ __disable_trace_kprobe(tp);
if (file)
- trace_probe_remove_file(&tk->tp, file);
+ trace_probe_remove_file(tp, file);
else
- trace_probe_clear_flag(&tk->tp, TP_FLAG_PROFILE);
+ trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
}
return ret;
@@ -326,11 +398,14 @@ enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
* 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 trace_probe *tp = &tk->tp;
- int ret = 0;
+ struct trace_probe *tp;
+
+ tp = trace_probe_primary_from_call(call);
+ if (WARN_ON_ONCE(!tp))
+ return -ENODEV;
if (file) {
if (!trace_probe_get_file_link(tp, file))
@@ -341,12 +416,8 @@ disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
} else
trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
- if (!trace_probe_is_enabled(tp) && trace_kprobe_is_registered(tk)) {
- if (trace_kprobe_is_return(tk))
- disable_kretprobe(&tk->rp);
- else
- disable_kprobe(&tk->rp.kp);
- }
+ if (!trace_probe_is_enabled(tp))
+ __disable_trace_kprobe(tp);
out:
if (file)
@@ -358,7 +429,7 @@ disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
*/
trace_probe_remove_file(tp, file);
- return ret;
+ return 0;
}
#if defined(CONFIG_KPROBES_ON_FTRACE) && \
@@ -437,6 +508,10 @@ static void __unregister_trace_kprobe(struct trace_kprobe *tk)
/* 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;
@@ -445,12 +520,81 @@ static int unregister_trace_kprobe(struct trace_kprobe *tk)
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;
+ struct trace_probe *pos;
+ int i;
+
+ list_for_each_entry(pos, &tpe->probes, list) {
+ orig = container_of(pos, struct trace_kprobe, tp);
+ 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))
+ continue;
+ }
+
+ 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);
+
+ return ret;
+}
+
/* Register a trace_probe and probe_event */
static int register_trace_kprobe(struct trace_kprobe *tk)
{
@@ -459,14 +603,17 @@ 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_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 */
@@ -700,7 +847,7 @@ static int trace_kprobe_create(int argc, const char *argv[])
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;
}
@@ -965,6 +1112,9 @@ retry:
case FETCH_OP_COMM:
val = (unsigned long)current->comm;
break;
+ case FETCH_OP_DATA:
+ val = (unsigned long)code->data;
+ break;
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
case FETCH_OP_ARG:
val = regs_get_kernel_argument(regs, code->param);
@@ -1089,7 +1239,10 @@ print_kprobe_event(struct trace_iterator *iter, int flags,
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_probe_name(tp));
@@ -1116,7 +1269,10 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,
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_probe_name(tp));
@@ -1145,23 +1301,31 @@ static int kprobe_event_define_fields(struct trace_event_call *event_call)
{
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
@@ -1289,20 +1453,19 @@ int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type,
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:
@@ -1369,7 +1532,6 @@ static inline void init_trace_event_call(struct trace_kprobe *tk)
call->flags = TRACE_EVENT_FL_KPROBE;
call->class->reg = kprobe_register;
- call->data = tk;
}
static int register_kprobe_event(struct trace_kprobe *tk)
@@ -1432,7 +1594,9 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call)
{
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);
@@ -1577,7 +1741,8 @@ static __init int kprobe_trace_self_tests_init(void)
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);
}
}
@@ -1598,7 +1763,8 @@ static __init int kprobe_trace_self_tests_init(void)
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);
}
}
@@ -1631,7 +1797,8 @@ static __init int kprobe_trace_self_tests_init(void)
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);
@@ -1649,7 +1816,8 @@ static __init int kprobe_trace_self_tests_init(void)
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);