Make trust DB auto sizing the default

Change the default daemon configuration to auto sizing with the existing baseline size, and make numeric db_max_size values explicitly disable automatic resizing. Update the shipped configuration and man page so installed defaults match runtime defaults.

Author: stevegrubb

doc/fapolicyd.conf.5

@@ -38,10 +38,10 @@ This option controls whether (1) or not (0) fapolicyd should add subject and obj
 .B db_max_size
 This option controls how many megabytes to allow the trust database to grow to.
 If you have lots of packages installed, then you want to make it bigger. The
-default value is 100 megabytes. The special value "auto" tells the daemon to
-size the trust database based on current utilization whenever it starts or
-rebuilds the database. Auto sizing targets roughly 75% active database usage,
-keeps lower-utilization reload headroom for the current trust database
+default value is "auto", which tells the daemon to size the trust database
+based on current utilization whenever it starts or rebuilds the database. Auto
+sizing starts from a 100 megabyte baseline, targets roughly 75% active database
+usage, keeps lower-utilization reload headroom for the current trust database
 generation and the candidate generation being built, grows when needed, and
 shrinks conservatively when utilization is low.
 

init/fapolicyd.conf

@@ -10,7 +10,7 @@ uid = fapolicyd
 gid = fapolicyd
 do_stat_report = 1
 detailed_report = 1
-db_max_size = 100
+db_max_size = auto
 subj_cache_size = 4099
 obj_cache_size = 8191
 watch_fs = ext2,ext3,ext4,tmpfs,xfs,vfat,iso9660,btrfs

src/library/conf.h

@@ -51,7 +51,7 @@ typedef struct conf
 	unsigned int do_stat_report;
 	unsigned int detailed_report;
 	unsigned int db_max_size;
-	bool do_audit_db_sizing;
+	bool do_auto_db_sizing;
 	unsigned int subj_cache_size;
 	unsigned int obj_cache_size;
 	const char *watch_fs;

src/library/daemon-config.c

@@ -141,8 +141,8 @@ static void clear_daemon_config(conf_t *config)
 	config->gid = 0;
 	config->do_stat_report = 1;
 	config->detailed_report = 1;
-	config->db_max_size = 100;
-	config->do_audit_db_sizing = false;
+	config->db_max_size = get_default_db_max_size();
+	config->do_auto_db_sizing = true;
 	config->subj_cache_size = 4099;
 	config->obj_cache_size = 8191;
 	config->watch_fs = strdup("ext4,xfs,tmpfs");
@@ -504,15 +504,22 @@ static int detailed_report_parser(const struct nv_pair *nv, int line,
 static int db_max_size_parser(const struct nv_pair *nv, int line,
 		conf_t *config)
 {
-	// "auto" triggers utilisation‑based sizing, anything else
-	// remains the legacy integer in MiB.
+	unsigned int db_max_size = config->db_max_size;
+
+	// "auto" keeps utilization-based sizing enabled. A numeric value is an
+	// explicit administrator override and keeps the legacy fixed MiB limit.
 	if (strcmp(nv->value, "auto") == 0) {
-		config->do_audit_db_sizing = true;
 		config->db_max_size = get_default_db_max_size();
+		config->do_auto_db_sizing = true;
 		return 0;
 	}
 
-	return unsigned_int_parser(&(config->db_max_size), nv->value, line);
+	if (unsigned_int_parser(&db_max_size, nv->value, line))
+		return 1;
+
+	config->db_max_size = db_max_size;
+	config->do_auto_db_sizing = false;
+	return 0;
 }
 
 static int subj_cache_size_parser(const struct nv_pair *nv, int line,

src/library/database.c

@@ -2426,7 +2426,7 @@ static int autosize_reload_preflight(conf_t *config)
 		return 0;
 	}
 
-	if (!config->do_audit_db_sizing) {
+	if (!config->do_auto_db_sizing) {
 		if (state.recommended_pages > state.map_pages)
 			msg(LOG_WARNING,
 			    "db_max_size may be too small for safe reload: "
@@ -2914,21 +2914,21 @@ static void check_db_size(const conf_t *config)
 	    state.allocated_percent);
 	if (state.allocated_percent > TRUST_DB_RELOAD_HIGHWATER_PERCENT &&
 	    state.allocated_percent > state.active_percent) {
-		int priority = config->do_audit_db_sizing ? LOG_INFO :
+		int priority = config->do_auto_db_sizing ? LOG_INFO :
 			       LOG_WARNING;
 
 		msg(priority,
 		    "Trust database LMDB map high-water at %lu%% capacity "
 		    "while active DB pages are at %lu%%",
 		    state.allocated_percent, state.active_percent);
-		if (!config->do_audit_db_sizing)
+		if (!config->do_auto_db_sizing)
 			log_lmdb_state(LOG_WARNING,
 				       "trust database size check", 0);
 	}
 
 	target_mb = autosize_effective_target_mb(&state,
 						 AUTOSIZE_LIVE_INSPECTION);
-	if (config->do_audit_db_sizing) {
+	if (config->do_auto_db_sizing) {
 		if (target_mb > config->db_max_size) {
 			if (state.active_target_pages > state.map_pages)
 				msg(LOG_INFO,
@@ -2993,7 +2993,7 @@ static void database_resize_report(FILE *f, const conf_t *config)
 	unsigned int target_mb = 0;
 	int rc;
 
-	if (config == NULL || config->do_audit_db_sizing)
+	if (config == NULL || config->do_auto_db_sizing)
 		return;
 
 	rc = read_live_lmdb_sizing_state(&state);
@@ -4104,7 +4104,7 @@ static int create_database_for_generation(struct trust_db_generation *gen,
 			       rc == WRITE_DB_MAP_FULL ? MDB_MAP_FULL : 0);
 
 		if (rc == WRITE_DB_MAP_FULL &&
-		    config->do_audit_db_sizing && retries == 0) {
+		    config->do_auto_db_sizing && retries == 0) {
 			int grown;
 
 			lock_update_thread();
@@ -4650,7 +4650,7 @@ int init_database(conf_t *config)
 		return 1;
 
 	/* One-shot utilisation-driven sizing */
-	if (config->do_audit_db_sizing &&
+	if (config->do_auto_db_sizing &&
 	    autosize_database(config, AUTOSIZE_STARTUP_INSPECTION))
 		msg(LOG_INFO, "autosize: map size recomputed to %u MiB",
 		    config->db_max_size);
@@ -5528,7 +5528,7 @@ static int do_reload_db(conf_t *config)
 	backend_close();
 
 	/* One-shot utilisation-driven sizing */
-	if (config->do_audit_db_sizing &&
+	if (config->do_auto_db_sizing &&
 	    autosize_database(config, AUTOSIZE_LIVE_INSPECTION)) {
 		msg(LOG_INFO, "autosize: map size recomputed to %u MiB",
 			config->db_max_size);

src/tests/trustdb_lmdb_test.c

@@ -803,15 +803,15 @@ static int test_lmdb_manual_resize_report_is_gated(void)
 	 * administrator's numeric db_max_size, not LMDB's current file size.
 	 */
 	cfg.db_max_size = 1;
-	cfg.do_audit_db_sizing = false;
+	cfg.do_auto_db_sizing = false;
 	CHECK(read_database_utilization_text(&cfg, report, sizeof(report)) == 0,
 	      116, "[ERROR:116] manual resize report failed");
 	CHECK(strstr(report, "Trust database resize recommended: yes") != NULL,
 	      117, "[ERROR:117] manual resize recommendation missing");
 	CHECK(strstr(report, "Trust database resize target:") != NULL,
 	      118, "[ERROR:118] manual resize target missing");
 
-	cfg.do_audit_db_sizing = true;
+	cfg.do_auto_db_sizing = true;
 	CHECK(read_database_utilization_text(&cfg, report, sizeof(report)) == 0,
 	      119, "[ERROR:119] auto resize report failed");
 	CHECK(strstr(report, "Trust database resize recommended:") == NULL,