X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fust-registry.c;h=3f1390dc3df1e65449700c12fa502215a9e29426;hp=19cff09fcd9d26aedb4a79194d10f7875e5fc810;hb=b4d096a6292e78c601dba161dbb15f48ad89935f;hpb=7972aab22f74b18faa168c0482216a3dd711a075

diff --git a/src/bin/lttng-sessiond/ust-registry.c b/src/bin/lttng-sessiond/ust-registry.c
index 19cff09fc..3f1390dc3 100644
--- a/src/bin/lttng-sessiond/ust-registry.c
+++ b/src/bin/lttng-sessiond/ust-registry.c
@@ -15,6 +15,7 @@
  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 #define _GNU_SOURCE
+#define _LGPL_SOURCE
 #include <assert.h>
 #include <inttypes.h>
 
@@ -23,6 +24,8 @@
 #include <lttng/lttng.h>
 
 #include "ust-registry.h"
+#include "ust-app.h"
+#include "utils.h"
 
 /*
  * Hash table match function for event in the registry.
@@ -40,13 +43,13 @@ static int ht_match_event(struct cds_lfht_node *node, const void *_key)
 	key = _key;
 
 	/* It has to be a perfect match. */
-	if (strncmp(event->name, key->name, sizeof(event->name)) != 0) {
+	if (strncmp(event->name, key->name, sizeof(event->name))) {
 		goto no_match;
 	}
 
 	/* It has to be a perfect match. */
 	if (strncmp(event->signature, key->signature,
-				strlen(event->signature) != 0)) {
+			strlen(event->signature))) {
 		goto no_match;
 	}
 
@@ -70,16 +73,78 @@ static unsigned long ht_hash_event(void *_key, unsigned long seed)
 	return hash_key_u64(&xored_key, seed);
 }
 
+/*
+ * Return negative value on error, 0 if OK.
+ *
+ * TODO: we could add stricter verification of more types to catch
+ * errors in liblttng-ust implementation earlier than consumption by the
+ * trace reader.
+ */
+static
+int validate_event_field(struct ustctl_field *field,
+		const char *event_name,
+		struct ust_app *app)
+{
+	switch(field->type.atype) {
+	case ustctl_atype_integer:
+	case ustctl_atype_enum:
+	case ustctl_atype_array:
+	case ustctl_atype_sequence:
+	case ustctl_atype_string:
+		break;
+
+	case ustctl_atype_float:
+		switch (field->type.u.basic._float.mant_dig) {
+		case 0:
+			WARN("UST application '%s' (pid: %d) has unknown float mantissa '%u' "
+				"in field '%s', rejecting event '%s'",
+				app->name, app->pid,
+				field->type.u.basic._float.mant_dig,
+				field->name,
+				event_name);
+			return -EINVAL;
+		default:
+			break;
+		}
+		break;
+
+	default:
+		return -ENOENT;
+	}
+	return 0;
+}
+
+static
+int validate_event_fields(size_t nr_fields, struct ustctl_field *fields,
+		const char *event_name, struct ust_app *app)
+{
+	unsigned int i;
+
+	for (i = 0; i < nr_fields; i++) {
+		if (validate_event_field(&fields[i], event_name, app) < 0)
+			return -EINVAL;
+	}
+	return 0;
+}
+
 /*
  * Allocate event and initialize it. This does NOT set a valid event id from a
  * registry.
  */
 static struct ust_registry_event *alloc_event(int session_objd,
 		int channel_objd, char *name, char *sig, size_t nr_fields,
-		struct ustctl_field *fields, int loglevel, char *model_emf_uri)
+		struct ustctl_field *fields, int loglevel, char *model_emf_uri,
+		struct ust_app *app)
 {
 	struct ust_registry_event *event = NULL;
 
+	/*
+	 * Ensure that the field content is valid.
+	 */
+	if (validate_event_fields(nr_fields, fields, name, app) < 0) {
+		return NULL;
+	}
+
 	event = zmalloc(sizeof(*event));
 	if (!event) {
 		PERROR("zmalloc ust registry event");
@@ -184,7 +249,8 @@ end:
 int ust_registry_create_event(struct ust_registry_session *session,
 		uint64_t chan_key, int session_objd, int channel_objd, char *name,
 		char *sig, size_t nr_fields, struct ustctl_field *fields, int loglevel,
-		char *model_emf_uri, int buffer_type, uint32_t *event_id_p)
+		char *model_emf_uri, int buffer_type, uint32_t *event_id_p,
+		struct ust_app *app)
 {
 	int ret;
 	uint32_t event_id;
@@ -197,34 +263,34 @@ int ust_registry_create_event(struct ust_registry_session *session,
 	assert(sig);
 	assert(event_id_p);
 
+	rcu_read_lock();
+
 	/*
 	 * This should not happen but since it comes from the UST tracer, an
 	 * external party, don't assert and simply validate values.
 	 */
 	if (session_objd < 0 || channel_objd < 0) {
 		ret = -EINVAL;
-		goto error;
+		goto error_free;
 	}
 
-	rcu_read_lock();
-
 	chan = ust_registry_channel_find(session, chan_key);
 	if (!chan) {
 		ret = -EINVAL;
-		goto error_unlock;
+		goto error_free;
 	}
 
 	/* Check if we've reached the maximum possible id. */
 	if (ust_registry_is_max_id(chan->used_event_id)) {
 		ret = -ENOENT;
-		goto error_unlock;
+		goto error_free;
 	}
 
 	event = alloc_event(session_objd, channel_objd, name, sig, nr_fields,
-			fields, loglevel, model_emf_uri);
+			fields, loglevel, model_emf_uri, app);
 	if (!event) {
 		ret = -ENOMEM;
-		goto error_unlock;
+		goto error_free;
 	}
 
 	DBG3("UST registry creating event with event: %s, sig: %s, id: %u, "
@@ -278,9 +344,12 @@ int ust_registry_create_event(struct ust_registry_session *session,
 	rcu_read_unlock();
 	return 0;
 
+error_free:
+	free(sig);
+	free(fields);
+	free(model_emf_uri);
 error_unlock:
 	rcu_read_unlock();
-error:
 	destroy_event(event);
 	return ret;
 }
@@ -308,12 +377,29 @@ void ust_registry_destroy_event(struct ust_registry_channel *chan,
 	return;
 }
 
+/*
+ * We need to execute ht_destroy outside of RCU read-side critical
+ * section and outside of call_rcu thread, so we postpone its execution
+ * using ht_cleanup_push. It is simpler than to change the semantic of
+ * the many callers of delete_ust_app_session().
+ */
+static
+void destroy_channel_rcu(struct rcu_head *head)
+{
+	struct ust_registry_channel *chan =
+		caa_container_of(head, struct ust_registry_channel, rcu_head);
+
+	if (chan->ht) {
+		ht_cleanup_push(chan->ht);
+	}
+	free(chan->ctx_fields);
+	free(chan);
+}
+
 /*
  * Destroy every element of the registry and free the memory. This does NOT
  * free the registry pointer since it might not have been allocated before so
  * it's the caller responsability.
- *
- * This MUST be called within a RCU read side lock section.
  */
 static void destroy_channel(struct ust_registry_channel *chan)
 {
@@ -322,14 +408,14 @@ static void destroy_channel(struct ust_registry_channel *chan)
 
 	assert(chan);
 
+	rcu_read_lock();
 	/* Destroy all event associated with this registry. */
 	cds_lfht_for_each_entry(chan->ht->ht, &iter.iter, event, node.node) {
 		/* Delete the node from the ht and free it. */
 		ust_registry_destroy_event(chan, event);
 	}
-	lttng_ht_destroy(chan->ht);
-
-	free(chan);
+	rcu_read_unlock();
+	call_rcu(&chan->rcu_head, destroy_channel_rcu);
 }
 
 /*
@@ -347,7 +433,7 @@ int ust_registry_channel_add(struct ust_registry_session *session,
 	if (!chan) {
 		PERROR("zmalloc ust registry channel");
 		ret = -ENOMEM;
-		goto error;
+		goto error_alloc;
 	}
 
 	chan->ht = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
@@ -376,7 +462,11 @@ int ust_registry_channel_add(struct ust_registry_session *session,
 	lttng_ht_add_unique_u64(session->channels, &chan->node);
 	rcu_read_unlock();
 
+	return 0;
+
 error:
+	destroy_channel(chan);
+error_alloc:
 	return ret;
 }
 
@@ -418,22 +508,24 @@ void ust_registry_channel_del_free(struct ust_registry_session *session,
 {
 	struct lttng_ht_iter iter;
 	struct ust_registry_channel *chan;
+	int ret;
 
 	assert(session);
 
 	rcu_read_lock();
 	chan = ust_registry_channel_find(session, key);
 	if (!chan) {
+		rcu_read_unlock();
 		goto end;
 	}
 
 	iter.iter.node = &chan->node.node;
-	lttng_ht_del(session->channels, &iter);
-
+	ret = lttng_ht_del(session->channels, &iter);
+	assert(!ret);
+	rcu_read_unlock();
 	destroy_channel(chan);
 
 end:
-	rcu_read_unlock();
 	return;
 }
 
@@ -452,18 +544,23 @@ int ust_registry_session_init(struct ust_registry_session **sessionp,
 		uint32_t uint32_t_alignment,
 		uint32_t uint64_t_alignment,
 		uint32_t long_alignment,
-		int byte_order)
+		int byte_order,
+		uint32_t major,
+		uint32_t minor,
+		const char *root_shm_path,
+		const char *shm_path,
+		uid_t euid,
+		gid_t egid)
 {
 	int ret;
 	struct ust_registry_session *session;
 
 	assert(sessionp);
-	assert(app);
 
 	session = zmalloc(sizeof(*session));
 	if (!session) {
 		PERROR("zmalloc ust registry session");
-		goto error;
+		goto error_alloc;
 	}
 
 	pthread_mutex_init(&session->lock, NULL);
@@ -474,6 +571,43 @@ int ust_registry_session_init(struct ust_registry_session **sessionp,
 	session->uint64_t_alignment = uint64_t_alignment;
 	session->long_alignment = long_alignment;
 	session->byte_order = byte_order;
+	session->metadata_fd = -1;
+	session->uid = euid;
+	session->gid = egid;
+	strncpy(session->root_shm_path, root_shm_path,
+		sizeof(session->root_shm_path));
+	session->root_shm_path[sizeof(session->root_shm_path) - 1] = '\0';
+	if (shm_path[0]) {
+		strncpy(session->shm_path, shm_path,
+			sizeof(session->shm_path));
+		session->shm_path[sizeof(session->shm_path) - 1] = '\0';
+		strncpy(session->metadata_path, shm_path,
+			sizeof(session->metadata_path));
+		session->metadata_path[sizeof(session->metadata_path) - 1] = '\0';
+		strncat(session->metadata_path, "/metadata",
+			sizeof(session->metadata_path)
+				- strlen(session->metadata_path) - 1);
+	}
+	if (session->shm_path[0]) {
+		ret = run_as_mkdir_recursive(session->shm_path,
+			S_IRWXU | S_IRWXG,
+			euid, egid);
+		if (ret) {
+			PERROR("run_as_mkdir_recursive");
+			goto error;
+		}
+	}
+	if (session->metadata_path[0]) {
+		/* Create metadata file */
+		ret = run_as_open(session->metadata_path,
+			O_WRONLY | O_CREAT | O_EXCL,
+			S_IRUSR | S_IWUSR, euid, egid);
+		if (ret < 0) {
+			PERROR("Opening metadata file");
+			goto error;
+		}
+		session->metadata_fd = ret;
+	}
 
 	session->channels = lttng_ht_new(0, LTTNG_HT_TYPE_U64);
 	if (!session->channels) {
@@ -487,7 +621,7 @@ int ust_registry_session_init(struct ust_registry_session **sessionp,
 	}
 
 	pthread_mutex_lock(&session->lock);
-	ret = ust_metadata_session_statedump(session, app);
+	ret = ust_metadata_session_statedump(session, app, major, minor);
 	pthread_mutex_unlock(&session->lock);
 	if (ret) {
 		ERR("Failed to generate session metadata (errno = %d)", ret);
@@ -499,6 +633,9 @@ int ust_registry_session_init(struct ust_registry_session **sessionp,
 	return 0;
 
 error:
+	ust_registry_session_destroy(session);
+	free(session);
+error_alloc:
 	return -1;
 }
 
@@ -512,20 +649,45 @@ void ust_registry_session_destroy(struct ust_registry_session *reg)
 	struct lttng_ht_iter iter;
 	struct ust_registry_channel *chan;
 
+	if (!reg) {
+		return;
+	}
+
 	/* On error, EBUSY can be returned if lock. Code flow error. */
 	ret = pthread_mutex_destroy(&reg->lock);
 	assert(!ret);
 
-	rcu_read_lock();
-	/* Destroy all event associated with this registry. */
-	cds_lfht_for_each_entry(reg->channels->ht, &iter.iter, chan, node.node) {
-		/* Delete the node from the ht and free it. */
-		ret = lttng_ht_del(reg->channels, &iter);
-		assert(!ret);
-		destroy_channel(chan);
+	if (reg->channels) {
+		rcu_read_lock();
+		/* Destroy all event associated with this registry. */
+		cds_lfht_for_each_entry(reg->channels->ht, &iter.iter, chan,
+				node.node) {
+			/* Delete the node from the ht and free it. */
+			ret = lttng_ht_del(reg->channels, &iter);
+			assert(!ret);
+			destroy_channel(chan);
+		}
+		rcu_read_unlock();
+		ht_cleanup_push(reg->channels);
 	}
-	lttng_ht_destroy(reg->channels);
-	rcu_read_unlock();
 
 	free(reg->metadata);
+	if (reg->metadata_fd >= 0) {
+		ret = close(reg->metadata_fd);
+		if (ret) {
+			PERROR("close");
+		}
+		ret = run_as_unlink(reg->metadata_path,
+				reg->uid, reg->gid);
+		if (ret) {
+			PERROR("unlink");
+		}
+	}
+	if (reg->root_shm_path[0]) {
+		/*
+		 * Try deleting the directory hierarchy.
+		 */
+		(void) run_as_recursive_rmdir(reg->root_shm_path,
+				reg->uid, reg->gid);
+	}
 }