[lttng-tools.git] / src / common / event-rule / kprobe.c

/*
 * Copyright (C) 2019 Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
 *
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 */

#include <assert.h>
#include <common/credentials.h>
#include <common/error.h>
#include <common/macros.h>
#include <common/payload.h>
#include <common/payload-view.h>
#include <common/runas.h>
#include <common/hashtable/hashtable.h>
#include <common/hashtable/utils.h>
#include <ctype.h>
#include <lttng/constant.h>
#include <lttng/event-rule/event-rule-internal.h>
#include <lttng/event-rule/kprobe-internal.h>
#include <lttng/kernel-probe.h>
#include <lttng/kernel-probe-internal.h>
#include <stdio.h>

#define IS_KPROBE_EVENT_RULE(rule) \
	(lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KPROBE)

#if (LTTNG_SYMBOL_NAME_LEN == 256)
#define LTTNG_SYMBOL_NAME_LEN_SCANF_IS_A_BROKEN_API "255"
#endif

static void lttng_event_rule_kprobe_destroy(struct lttng_event_rule *rule)
{
	struct lttng_event_rule_kprobe *kprobe;

	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);

	lttng_kernel_probe_location_destroy(kprobe->location);
	free(kprobe->name);
	free(kprobe);
}

static bool lttng_event_rule_kprobe_validate(
		const struct lttng_event_rule *rule)
{
	bool valid = false;
	struct lttng_event_rule_kprobe *kprobe;

	if (!rule) {
		goto end;
	}

	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);

	/* Required field. */
	if (!kprobe->name) {
		ERR("Invalid name event rule: a name must be set.");
		goto end;
	}

	/* Required field. */
	if(!kprobe->location) {
		ERR("Invalid name event rule: a location must be set.");
		goto end;
	}

	valid = true;
end:
	return valid;
}

static int lttng_event_rule_kprobe_serialize(
		const struct lttng_event_rule *rule,
		struct lttng_payload *payload)
{
	int ret;
	size_t name_len, header_offset, size_before_location;
	struct lttng_event_rule_kprobe *kprobe;
	struct lttng_event_rule_kprobe_comm kprobe_comm;
	struct lttng_event_rule_kprobe_comm *header;

	if (!rule || !IS_KPROBE_EVENT_RULE(rule)) {
		ret = -1;
		goto end;
	}

	header_offset = payload->buffer.size;

	DBG("Serializing kprobe event rule.");
	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);

	name_len = strlen(kprobe->name) + 1;
	kprobe_comm.name_len = name_len;

	ret = lttng_dynamic_buffer_append(
			&payload->buffer, &kprobe_comm, sizeof(kprobe_comm));
	if (ret) {
		goto end;
	}

	ret = lttng_dynamic_buffer_append(&payload->buffer, kprobe->name, name_len);
	if (ret) {
		goto end;
	}

	size_before_location = payload->buffer.size;

	ret = lttng_kernel_probe_location_serialize(kprobe->location, payload);
	if (ret < 0) {
		goto end;
	}

	/* Update the header regarding the probe size. */
	header = (struct lttng_event_rule_kprobe_comm*) (
			(char *) payload->buffer.data + header_offset);
	header->location_len = payload->buffer.size - size_before_location;

	ret = 0;

end:
	return ret;
}

static bool lttng_event_rule_kprobe_is_equal(const struct lttng_event_rule *_a,
		const struct lttng_event_rule *_b)
{
	bool is_equal = false;
	struct lttng_event_rule_kprobe *a, *b;

	a = container_of(_a, struct lttng_event_rule_kprobe, parent);
	b = container_of(_b, struct lttng_event_rule_kprobe, parent);

	/* Quick checks */
	if (!!a->name != !!b->name) {
		goto end;
	}

	/* Long check */
	assert(a->name);
	assert(b->name);
	if (strcmp(a->name, b->name)) {
		goto end;
	}

	is_equal = lttng_kernel_probe_location_is_equal(
			a->location, b->location);
end:
	return is_equal;
}

static enum lttng_error_code lttng_event_rule_kprobe_generate_filter_bytecode(
		struct lttng_event_rule *rule,
		const struct lttng_credentials *creds)
{
	/* Nothing to do. */
	return LTTNG_OK;
}

static const char *lttng_event_rule_kprobe_get_filter(
		const struct lttng_event_rule *rule)
{
	/* Not supported. */
	return NULL;
}

static const struct lttng_filter_bytecode *
lttng_event_rule_kprobe_get_filter_bytecode(const struct lttng_event_rule *rule)
{
	/* Not supported. */
	return NULL;
}

static enum lttng_event_rule_generate_exclusions_status
lttng_event_rule_kprobe_generate_exclusions(const struct lttng_event_rule *rule,
		struct lttng_event_exclusion **exclusions)
{
	/* Not supported. */
	*exclusions = NULL;
	return LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE;
}

static unsigned long
lttng_event_rule_kprobe_hash(
		const struct lttng_event_rule *rule)
{
	unsigned long hash;
	struct lttng_event_rule_kprobe *krule =
			container_of(rule, typeof(*krule), parent);

	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KPROBE,
			lttng_ht_seed);
	hash ^= hash_key_str(krule->name, lttng_ht_seed);
	hash ^= lttng_kernel_probe_location_hash(krule->location);

	return hash;
}

struct lttng_event_rule *lttng_event_rule_kprobe_create(void)
{
	struct lttng_event_rule *rule = NULL;
	struct lttng_event_rule_kprobe *krule;

	krule = zmalloc(sizeof(struct lttng_event_rule_kprobe));
	if (!krule) {
		goto end;
	}

	rule = &krule->parent;
	lttng_event_rule_init(&krule->parent, LTTNG_EVENT_RULE_TYPE_KPROBE);
	krule->parent.validate = lttng_event_rule_kprobe_validate;
	krule->parent.serialize = lttng_event_rule_kprobe_serialize;
	krule->parent.equal = lttng_event_rule_kprobe_is_equal;
	krule->parent.destroy = lttng_event_rule_kprobe_destroy;
	krule->parent.generate_filter_bytecode =
			lttng_event_rule_kprobe_generate_filter_bytecode;
	krule->parent.get_filter = lttng_event_rule_kprobe_get_filter;
	krule->parent.get_filter_bytecode =
			lttng_event_rule_kprobe_get_filter_bytecode;
	krule->parent.generate_exclusions =
			lttng_event_rule_kprobe_generate_exclusions;
	krule->parent.hash = lttng_event_rule_kprobe_hash;
end:
	return rule;
}

LTTNG_HIDDEN
ssize_t lttng_event_rule_kprobe_create_from_payload(
		struct lttng_payload_view *view,
		struct lttng_event_rule **_event_rule)
{
	ssize_t ret, offset = 0;
	enum lttng_event_rule_status status;
	const struct lttng_event_rule_kprobe_comm *kprobe_comm;
	const char *name;
	struct lttng_buffer_view current_buffer_view;
	struct lttng_event_rule *rule = NULL;
	struct lttng_event_rule_kprobe *kprobe = NULL;
	struct lttng_kernel_probe_location *location;

	if (!_event_rule) {
		ret = -1;
		goto end;
	}

	current_buffer_view = lttng_buffer_view_from_view(
			&view->buffer, offset, sizeof(*kprobe_comm));
	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
		ERR("Failed to initialize from malformed event rule kprobe: buffer too short to contain header.");
		ret = -1;
		goto end;
	}

	kprobe_comm = (typeof(kprobe_comm)) current_buffer_view.data;

	rule = lttng_event_rule_kprobe_create();
	if (!rule) {
		ERR("Failed to create event rule kprobe.");
		ret = -1;
		goto end;
	}

	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);

	/* Skip to payload */
	offset += current_buffer_view.size;

	{
		/* Map the name. */
		struct lttng_payload_view current_payload_view =
				lttng_payload_view_from_view(view, offset,
						kprobe_comm->name_len);

		if (!lttng_payload_view_is_valid(&current_payload_view)) {
			ret = -1;
			goto end;
		}

		name = current_payload_view.buffer.data;
		if (!lttng_buffer_view_contains_string(
				&current_payload_view.buffer, name,
				kprobe_comm->name_len)) {
			ret = -1;
			goto end;
		}
	}

	/* Skip after the name. */
	offset += kprobe_comm->name_len;

	/* Map the kernel probe location. */
	{
		struct lttng_payload_view current_payload_view =
				lttng_payload_view_from_view(view, offset,
						kprobe_comm->location_len);

		if (!lttng_payload_view_is_valid(&current_payload_view)) {
			ret = -1;
			goto end;
		}

		ret = lttng_kernel_probe_location_create_from_payload(
				&current_payload_view, &location);
		if (ret < 0) {
			ret = -1;
			goto end;
		}
	}

	if (ret != kprobe_comm->location_len) {
		ret = -1;
		goto end;
	}

	kprobe->location = location;

	/* Skip after the location */
	offset += kprobe_comm->location_len;

	status = lttng_event_rule_kprobe_set_name(rule, name);
	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
		ERR("Failed to set event rule kprobe name.");
		ret = -1;
		goto end;
	}

	*_event_rule = rule;
	rule = NULL;
	ret = offset;
end:
	lttng_event_rule_destroy(rule);
	return ret;
}

enum lttng_event_rule_status lttng_event_rule_kprobe_set_location(
		struct lttng_event_rule *rule,
		const struct lttng_kernel_probe_location *location)
{
	struct lttng_kernel_probe_location *location_copy = NULL;
	struct lttng_event_rule_kprobe *kprobe;
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;

	if (!rule || !IS_KPROBE_EVENT_RULE(rule) || !location) {
		status = LTTNG_EVENT_RULE_STATUS_INVALID;
		goto end;
	}

	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
	location_copy = lttng_kernel_probe_location_copy(location);
	if (!location_copy) {
		status = LTTNG_EVENT_RULE_STATUS_ERROR;
		goto end;
	}

	if (kprobe->location) {
		lttng_kernel_probe_location_destroy(kprobe->location);
	}

	kprobe->location = location_copy;
	location_copy = NULL;
end:
	lttng_kernel_probe_location_destroy(location_copy);
	return status;
}

enum lttng_event_rule_status lttng_event_rule_kprobe_get_location(
		const struct lttng_event_rule *rule,
		const struct lttng_kernel_probe_location **location)
{
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	struct lttng_event_rule_kprobe *kprobe;

	if (!rule || !IS_KPROBE_EVENT_RULE(rule) || !location) {
		status = LTTNG_EVENT_RULE_STATUS_INVALID;
		goto end;
	}

	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
	*location = kprobe->location;

	if (!*location) {
		status = LTTNG_EVENT_RULE_STATUS_UNSET;
		goto end;
	}

end:
	return status;
}

enum lttng_event_rule_status lttng_event_rule_kprobe_set_name(
		struct lttng_event_rule *rule, const char *name)
{
	char *name_copy = NULL;
	struct lttng_event_rule_kprobe *kprobe;
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;

	if (!rule || !IS_KPROBE_EVENT_RULE(rule) || !name ||
			strlen(name) == 0) {
		status = LTTNG_EVENT_RULE_STATUS_INVALID;
		goto end;
	}

	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
	name_copy = strdup(name);
	if (!name_copy) {
		status = LTTNG_EVENT_RULE_STATUS_ERROR;
		goto end;
	}

	free(kprobe->name);

	kprobe->name = name_copy;
	name_copy = NULL;
end:
	return status;
}

enum lttng_event_rule_status lttng_event_rule_kprobe_get_name(
		const struct lttng_event_rule *rule, const char **name)
{
	struct lttng_event_rule_kprobe *kprobe;
	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;

	if (!rule || !IS_KPROBE_EVENT_RULE(rule) || !name) {
		status = LTTNG_EVENT_RULE_STATUS_INVALID;
		goto end;
	}

	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
	if (!kprobe->name) {
		status = LTTNG_EVENT_RULE_STATUS_UNSET;
		goto end;
	}

	*name = kprobe->name;
end:
	return status;
}
Commit	Line	Data
077192fd JR	1	/*
	2	* Copyright (C) 2019 Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
	3	*
	4	* SPDX-License-Identifier: LGPL-2.1-only
	5	*
	6	*/
	7
	8	#include <assert.h>
58daac01	9	#include <common/credentials.h>
077192fd JR	10	#include <common/error.h>
	11	#include <common/macros.h>
	12	#include <common/payload.h>
	13	#include <common/payload-view.h>
	14	#include <common/runas.h>
959e3c66 JR	15	#include <common/hashtable/hashtable.h>
959e3c66 JR	16	#include <common/hashtable/utils.h>
077192fd JR	17	#include <ctype.h>
	18	#include <lttng/constant.h>
	19	#include <lttng/event-rule/event-rule-internal.h>
	20	#include <lttng/event-rule/kprobe-internal.h>
	21	#include <lttng/kernel-probe.h>
	22	#include <lttng/kernel-probe-internal.h>
	23	#include <stdio.h>
	24
	25	#define IS_KPROBE_EVENT_RULE(rule) \
	26	(lttng_event_rule_get_type(rule) == LTTNG_EVENT_RULE_TYPE_KPROBE)
	27
	28	#if (LTTNG_SYMBOL_NAME_LEN == 256)
	29	#define LTTNG_SYMBOL_NAME_LEN_SCANF_IS_A_BROKEN_API "255"
	30	#endif
	31
	32	static void lttng_event_rule_kprobe_destroy(struct lttng_event_rule *rule)
	33	{
	34	struct lttng_event_rule_kprobe *kprobe;
	35
	36	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
	37
	38	lttng_kernel_probe_location_destroy(kprobe->location);
	39	free(kprobe->name);
	40	free(kprobe);
	41	}
	42
	43	static bool lttng_event_rule_kprobe_validate(
	44	const struct lttng_event_rule *rule)
	45	{
	46	bool valid = false;
	47	struct lttng_event_rule_kprobe *kprobe;
	48
	49	if (!rule) {
	50	goto end;
	51	}
	52
	53	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
	54
	55	/* Required field. */
	56	if (!kprobe->name) {
	57	ERR("Invalid name event rule: a name must be set.");
	58	goto end;
	59	}
	60
	61	/* Required field. */
	62	if(!kprobe->location) {
	63	ERR("Invalid name event rule: a location must be set.");
	64	goto end;
	65	}
	66
	67	valid = true;
	68	end:
	69	return valid;
	70	}
	71
	72	static int lttng_event_rule_kprobe_serialize(
	73	const struct lttng_event_rule *rule,
	74	struct lttng_payload *payload)
	75	{
	76	int ret;
	77	size_t name_len, header_offset, size_before_location;
	78	struct lttng_event_rule_kprobe *kprobe;
	79	struct lttng_event_rule_kprobe_comm kprobe_comm;
	80	struct lttng_event_rule_kprobe_comm *header;
81
82	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule)) {
83	ret = -1;
84	goto end;
85	}
86
87	header_offset = payload->buffer.size;
88
89	DBG("Serializing kprobe event rule.");
90	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
91
92	name_len = strlen(kprobe->name) + 1;
93	kprobe_comm.name_len = name_len;
94
95	ret = lttng_dynamic_buffer_append(
96	&payload->buffer, &kprobe_comm, sizeof(kprobe_comm));
97	if (ret) {
98	goto end;
99	}
100
101	ret = lttng_dynamic_buffer_append(&payload->buffer, kprobe->name, name_len);
102	if (ret) {
103	goto end;
104	}
105
106	size_before_location = payload->buffer.size;
107
108	ret = lttng_kernel_probe_location_serialize(kprobe->location, payload);
109	if (ret < 0) {
110	goto end;
111	}
112
113	/* Update the header regarding the probe size. */
114	header = (struct lttng_event_rule_kprobe_comm*) (
115	(char *) payload->buffer.data + header_offset);
116	header->location_len = payload->buffer.size - size_before_location;
117
118	ret = 0;
119
120	end:
121	return ret;
122	}
123
124	static bool lttng_event_rule_kprobe_is_equal(const struct lttng_event_rule *_a,
125	const struct lttng_event_rule *_b)
126	{
127	bool is_equal = false;
128	struct lttng_event_rule_kprobe a, b;
129
130	a = container_of(_a, struct lttng_event_rule_kprobe, parent);
131	b = container_of(_b, struct lttng_event_rule_kprobe, parent);
132
133	/* Quick checks */
134	if (!!a->name != !!b->name) {
135	goto end;
136	}
137
138	/* Long check */
139	assert(a->name);
140	assert(b->name);
141	if (strcmp(a->name, b->name)) {
142	goto end;
143	}
144
145	is_equal = lttng_kernel_probe_location_is_equal(
146	a->location, b->location);
147	end:
148	return is_equal;
149	}
150
151	static enum lttng_error_code lttng_event_rule_kprobe_generate_filter_bytecode(
58daac01 JR	152	struct lttng_event_rule *rule,
58daac01 JR	153	const struct lttng_credentials *creds)
077192fd JR	154	{
	155	/* Nothing to do. */
	156	return LTTNG_OK;
	157	}
	158
	159	static const char *lttng_event_rule_kprobe_get_filter(
	160	const struct lttng_event_rule *rule)
	161	{
	162	/* Not supported. */
	163	return NULL;
	164	}
	165
	166	static const struct lttng_filter_bytecode *
	167	lttng_event_rule_kprobe_get_filter_bytecode(const struct lttng_event_rule *rule)
	168	{
	169	/* Not supported. */
	170	return NULL;
	171	}
	172
993578ff JR	173	static enum lttng_event_rule_generate_exclusions_status
	174	lttng_event_rule_kprobe_generate_exclusions(const struct lttng_event_rule *rule,
	175	struct lttng_event_exclusion **exclusions)
077192fd JR	176	{
077192fd JR	177	/* Not supported. */
993578ff JR	178	*exclusions = NULL;
993578ff JR	179	return LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE;
077192fd JR	180	}
077192fd JR	181
959e3c66 JR	182	static unsigned long
	183	lttng_event_rule_kprobe_hash(
	184	const struct lttng_event_rule *rule)
	185	{
	186	unsigned long hash;
	187	struct lttng_event_rule_kprobe *krule =
	188	container_of(rule, typeof(*krule), parent);
	189
	190	hash = hash_key_ulong((void *) LTTNG_EVENT_RULE_TYPE_KPROBE,
	191	lttng_ht_seed);
	192	hash ^= hash_key_str(krule->name, lttng_ht_seed);
	193	hash ^= lttng_kernel_probe_location_hash(krule->location);
	194
	195	return hash;
	196	}
	197
a3ecaea8	198	struct lttng_event_rule *lttng_event_rule_kprobe_create(void)
077192fd JR	199	{
	200	struct lttng_event_rule *rule = NULL;
	201	struct lttng_event_rule_kprobe *krule;
	202
	203	krule = zmalloc(sizeof(struct lttng_event_rule_kprobe));
	204	if (!krule) {
	205	goto end;
	206	}
	207
	208	rule = &krule->parent;
	209	lttng_event_rule_init(&krule->parent, LTTNG_EVENT_RULE_TYPE_KPROBE);
	210	krule->parent.validate = lttng_event_rule_kprobe_validate;
	211	krule->parent.serialize = lttng_event_rule_kprobe_serialize;
	212	krule->parent.equal = lttng_event_rule_kprobe_is_equal;
	213	krule->parent.destroy = lttng_event_rule_kprobe_destroy;
	214	krule->parent.generate_filter_bytecode =
	215	lttng_event_rule_kprobe_generate_filter_bytecode;
	216	krule->parent.get_filter = lttng_event_rule_kprobe_get_filter;
	217	krule->parent.get_filter_bytecode =
	218	lttng_event_rule_kprobe_get_filter_bytecode;
	219	krule->parent.generate_exclusions =
	220	lttng_event_rule_kprobe_generate_exclusions;
959e3c66	221	krule->parent.hash = lttng_event_rule_kprobe_hash;
077192fd JR	222	end:
	223	return rule;
	224	}
	225
	226	LTTNG_HIDDEN
	227	ssize_t lttng_event_rule_kprobe_create_from_payload(
	228	struct lttng_payload_view *view,
	229	struct lttng_event_rule **_event_rule)
	230	{
	231	ssize_t ret, offset = 0;
	232	enum lttng_event_rule_status status;
	233	const struct lttng_event_rule_kprobe_comm *kprobe_comm;
	234	const char *name;
	235	struct lttng_buffer_view current_buffer_view;
	236	struct lttng_event_rule *rule = NULL;
	237	struct lttng_event_rule_kprobe *kprobe = NULL;
	238	struct lttng_kernel_probe_location *location;
	239
	240	if (!_event_rule) {
	241	ret = -1;
	242	goto end;
	243	}
	244
3e6e0df2 JG	245	current_buffer_view = lttng_buffer_view_from_view(
	246	&view->buffer, offset, sizeof(*kprobe_comm));
	247	if (!lttng_buffer_view_is_valid(&current_buffer_view)) {
077192fd JR	248	ERR("Failed to initialize from malformed event rule kprobe: buffer too short to contain header.");
	249	ret = -1;
	250	goto end;
	251	}
	252
077192fd	253	kprobe_comm = (typeof(kprobe_comm)) current_buffer_view.data;
077192fd JR	254
	255	rule = lttng_event_rule_kprobe_create();
	256	if (!rule) {
	257	ERR("Failed to create event rule kprobe.");
	258	ret = -1;
	259	goto end;
	260	}
	261
	262	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
	263
	264	/* Skip to payload */
	265	offset += current_buffer_view.size;
	266
	267	{
	268	/* Map the name. */
	269	struct lttng_payload_view current_payload_view =
	270	lttng_payload_view_from_view(view, offset,
	271	kprobe_comm->name_len);
	272
3e6e0df2	273	if (!lttng_payload_view_is_valid(&current_payload_view)) {
077192fd JR	274	ret = -1;
	275	goto end;
	276	}
	277
3e6e0df2	278	name = current_payload_view.buffer.data;
077192fd JR	279	if (!lttng_buffer_view_contains_string(
	280	&current_payload_view.buffer, name,
	281	kprobe_comm->name_len)) {
	282	ret = -1;
	283	goto end;
	284	}
	285	}
	286
	287	/* Skip after the name. */
	288	offset += kprobe_comm->name_len;
	289
	290	/* Map the kernel probe location. */
	291	{
	292	struct lttng_payload_view current_payload_view =
	293	lttng_payload_view_from_view(view, offset,
	294	kprobe_comm->location_len);
	295
3e6e0df2 JG	296	if (!lttng_payload_view_is_valid(&current_payload_view)) {
	297	ret = -1;
	298	goto end;
	299	}
	300
077192fd JR	301	ret = lttng_kernel_probe_location_create_from_payload(
	302	&current_payload_view, &location);
	303	if (ret < 0) {
	304	ret = -1;
	305	goto end;
	306	}
	307	}
	308
	309	if (ret != kprobe_comm->location_len) {
	310	ret = -1;
	311	goto end;
	312	}
	313
	314	kprobe->location = location;
	315
	316	/* Skip after the location */
	317	offset += kprobe_comm->location_len;
	318
	319	status = lttng_event_rule_kprobe_set_name(rule, name);
	320	if (status != LTTNG_EVENT_RULE_STATUS_OK) {
	321	ERR("Failed to set event rule kprobe name.");
	322	ret = -1;
	323	goto end;
	324	}
	325
	326	*_event_rule = rule;
	327	rule = NULL;
	328	ret = offset;
	329	end:
	330	lttng_event_rule_destroy(rule);
	331	return ret;
	332	}
	333
	334	enum lttng_event_rule_status lttng_event_rule_kprobe_set_location(
	335	struct lttng_event_rule *rule,
	336	const struct lttng_kernel_probe_location *location)
	337	{
	338	struct lttng_kernel_probe_location *location_copy = NULL;
	339	struct lttng_event_rule_kprobe *kprobe;
	340	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
	341
	342	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !location) {
	343	status = LTTNG_EVENT_RULE_STATUS_INVALID;
	344	goto end;
	345	}
	346
	347	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
	348	location_copy = lttng_kernel_probe_location_copy(location);
	349	if (!location_copy) {
	350	status = LTTNG_EVENT_RULE_STATUS_ERROR;
	351	goto end;
	352	}
	353
	354	if (kprobe->location) {
	355	lttng_kernel_probe_location_destroy(kprobe->location);
	356	}
	357
	358	kprobe->location = location_copy;
	359	location_copy = NULL;
	360	end:
	361	lttng_kernel_probe_location_destroy(location_copy);
	362	return status;
	363	}
	364
365	enum lttng_event_rule_status lttng_event_rule_kprobe_get_location(
366	const struct lttng_event_rule *rule,
367	const struct lttng_kernel_probe_location **location)
368	{
369	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
370	struct lttng_event_rule_kprobe *kprobe;
371
372	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !location) {
373	status = LTTNG_EVENT_RULE_STATUS_INVALID;
374	goto end;
375	}
376
377	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
378	*location = kprobe->location;
379
380	if (!*location) {
381	status = LTTNG_EVENT_RULE_STATUS_UNSET;
382	goto end;
383	}
384
385	end:
386	return status;
387	}
388
389	enum lttng_event_rule_status lttng_event_rule_kprobe_set_name(
390	struct lttng_event_rule rule, const char name)
391	{
392	char *name_copy = NULL;
393	struct lttng_event_rule_kprobe *kprobe;
394	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
395
396	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !name \|\|
397	strlen(name) == 0) {
398	status = LTTNG_EVENT_RULE_STATUS_INVALID;
399	goto end;
400	}
401
402	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
403	name_copy = strdup(name);
404	if (!name_copy) {
405	status = LTTNG_EVENT_RULE_STATUS_ERROR;
406	goto end;
407	}
408
409	free(kprobe->name);
410
411	kprobe->name = name_copy;
412	name_copy = NULL;
413	end:
414	return status;
415	}
416
417	enum lttng_event_rule_status lttng_event_rule_kprobe_get_name(
418	const struct lttng_event_rule rule, const char *name)
419	{
420	struct lttng_event_rule_kprobe *kprobe;
421	enum lttng_event_rule_status status = LTTNG_EVENT_RULE_STATUS_OK;
422
423	if (!rule \|\| !IS_KPROBE_EVENT_RULE(rule) \|\| !name) {
424	status = LTTNG_EVENT_RULE_STATUS_INVALID;
425	goto end;
426	}
427
428	kprobe = container_of(rule, struct lttng_event_rule_kprobe, parent);
429	if (!kprobe->name) {
430	status = LTTNG_EVENT_RULE_STATUS_UNSET;
431	goto end;
432	}
433
434	*name = kprobe->name;
435	end:
436	return status;
437	}