X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fcmd.c;h=2f5a4e98c74978d8ac8d7480cb539bc595e2afd7;hp=dc442035a3fe21e6b4c487a1007c9f05d1b38c56;hb=fbc9f37df245d544a7705ba576297df791220b44;hpb=d7b377ed1acd4043bde353d99122e0e56fa4e975

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index dc442035a..2f5a4e98c 100644
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -3107,10 +3107,22 @@ enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
 			&payload,
 			0,
 			cmd_ctx->lsm.u.create_session.home_dir_size);
+	if (cmd_ctx->lsm.u.create_session.home_dir_size > 0 &&
+			!lttng_buffer_view_is_valid(&home_dir_view)) {
+		ERR("Invalid payload in \"create session\" command: buffer too short to contain home directory");
+		ret_code = LTTNG_ERR_INVALID_PROTOCOL;
+		goto error;
+	}
+
 	session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
 			&payload,
 			cmd_ctx->lsm.u.create_session.home_dir_size,
 			cmd_ctx->lsm.u.create_session.session_descriptor_size);
+	if (!lttng_buffer_view_is_valid(&session_descriptor_view)) {
+		ERR("Invalid payload in \"create session\" command: buffer too short to contain session descriptor");
+		ret_code = LTTNG_ERR_INVALID_PROTOCOL;
+		goto error;
+	}
 
 	ret = lttng_session_descriptor_create_from_buffer(
 			&session_descriptor_view, &session_descriptor);
@@ -4257,7 +4269,8 @@ end:
 }
 
 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
-		struct notification_thread_handle *notification_thread)
+		struct notification_thread_handle *notification_thread,
+		struct lttng_trigger **return_trigger)
 {
 	int ret;
 	size_t trigger_len;
@@ -4265,8 +4278,8 @@ int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
 	struct lttng_trigger *trigger = NULL;
 	struct lttng_payload trigger_payload;
 	struct lttng_credentials cmd_creds = {
-		.uid = cmd_ctx->creds.uid,
-		.gid = cmd_ctx->creds.gid,
+		.uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
+		.gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
 	};
 
 	lttng_payload_init(&trigger_payload);
@@ -4314,12 +4327,41 @@ int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
 		}
 	}
 
-	/* Set the trigger credential */
-	lttng_trigger_set_credentials(trigger, &cmd_creds);
+	/*
+	 * Validate the trigger credentials against the command credentials.
+	 * Only the root user can register a trigger with non-matching
+	 * credentials.
+	 */
+	if (!lttng_credentials_is_equal_uid(
+			lttng_trigger_get_credentials(trigger),
+			&cmd_creds)) {
+		if (lttng_credentials_get_uid(&cmd_creds) != 0) {
+			ERR("Trigger credentials do not match the command credentials");
+			ret = LTTNG_ERR_INVALID_TRIGGER;
+			goto end;
+		}
+	}
 
-	/* Inform the notification thread */
+	/*
+	 * A reference to the trigger is acquired by the notification thread.
+	 * It is safe to return the same trigger to the caller since it the
+	 * other user holds a reference.
+	 *
+	 * The trigger is modified during the execution of the
+	 * "register trigger" command. However, by the time the command returns,
+	 * it is safe to use without any locking as its properties are
+	 * immutable.
+	 */
 	ret = notification_thread_command_register_trigger(notification_thread,
 			trigger);
+	if (ret != LTTNG_OK) {
+		goto end_notification_thread;
+	}
+
+	/* Return an updated trigger to the client. */
+	*return_trigger = trigger;
+
+end_notification_thread:
 	/* Ownership of trigger was transferred. */
 	trigger = NULL;
 end:
@@ -4337,8 +4379,8 @@ int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
 	struct lttng_trigger *trigger = NULL;
 	struct lttng_payload trigger_payload;
 	struct lttng_credentials cmd_creds = {
-		.uid = cmd_ctx->creds.uid,
-		.gid = cmd_ctx->creds.gid,
+		.uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
+		.gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
 	};
 
 	lttng_payload_init(&trigger_payload);
@@ -4385,7 +4427,20 @@ int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
 		}
 	}
 
-	lttng_trigger_set_credentials(trigger, &cmd_creds);
+	/*
+	 * Validate the trigger credentials against the command credentials.
+	 * Only the root user can unregister a trigger with non-matching
+	 * credentials.
+	 */
+	if (!lttng_credentials_is_equal_uid(
+			lttng_trigger_get_credentials(trigger),
+			&cmd_creds)) {
+		if (lttng_credentials_get_uid(&cmd_creds) != 0) {
+			ERR("Trigger credentials do not match the command credentials");
+			ret = LTTNG_ERR_INVALID_TRIGGER;
+			goto end;
+		}
+	}
 
 	ret = notification_thread_command_unregister_trigger(notification_thread,
 			trigger);
@@ -4395,6 +4450,29 @@ end:
 	return ret;
 }
 
+int cmd_list_triggers(struct command_ctx *cmd_ctx,
+		struct notification_thread_handle *notification_thread,
+		struct lttng_triggers **return_triggers)
+{
+	int ret = 0;
+	enum lttng_error_code ret_code;
+	struct lttng_triggers *triggers = NULL;
+
+	/* Get the set of triggers from the notification thread. */
+	ret_code = notification_thread_command_list_triggers(
+			notification_thread, cmd_ctx->creds.uid, &triggers);
+	if (ret_code != LTTNG_OK) {
+		ret = ret_code;
+		goto end;
+	}
+
+	*return_triggers = triggers;
+	triggers = NULL;
+	ret = LTTNG_OK;
+end:
+	lttng_triggers_destroy(triggers);
+	return ret;
+}
 /*
  * Send relayd sockets from snapshot output to consumer. Ignore request if the
  * snapshot output is *not* set with a remote destination.