diff --git a/Assemble.c b/Assemble.c
index 704b829..9eac9ce 100644
--- a/Assemble.c
+++ b/Assemble.c
@@ -63,7 +63,7 @@ static void set_array_assembly_status(struct context *c,
 				   struct assembly_array_info *arr)
 {
 	int raid_disks = arr->preexist_cnt + arr->new_cnt;
-	char *status_msg = map_num(assemble_statuses, status);
+	char *status_msg = map_num_s(assemble_statuses, status);
 
 	if (c->export && result)
 		*result |= status;
@@ -77,9 +77,7 @@ static void set_array_assembly_status(struct context *c,
 		fprintf(stderr, " (%d new)", arr->new_cnt);
 	if (arr->exp_cnt)
 		fprintf(stderr, " ( + %d for expansion)", arr->exp_cnt);
-	if (status_msg)
-		fprintf(stderr, " %s", status_msg);
-	fprintf(stderr, ".\n");
+	fprintf(stderr, " %s.\n", status_msg);
 }
 
 static int name_matches(char *found, char *required, char *homehost, int require_homehost)
diff --git a/Create.c b/Create.c
index 9ea19de..c84c1ac 100644
--- a/Create.c
+++ b/Create.c
@@ -83,7 +83,7 @@ int default_layout(struct supertype *st, int level, int verbose)
 
 	if (layout_map) {
 		layout = map_name(layout_map, "default");
-		layout_name = map_num(layout_map, layout);
+		layout_name = map_num_s(layout_map, layout);
 	}
 	if (layout_name && verbose > 0)
 		pr_err("layout defaults to %s\n", layout_name);
diff --git a/Detail.c b/Detail.c
index 95d4cc7..ce7a844 100644
--- a/Detail.c
+++ b/Detail.c
@@ -495,8 +495,8 @@ int Detail(char *dev, struct context *c)
 			if (array.state & (1 << MD_SB_CLEAN)) {
 				if ((array.level == 0) ||
 				    (array.level == LEVEL_LINEAR))
-					arrayst = map_num(sysfs_array_states,
-							  sra->array_state);
+					arrayst = map_num_s(sysfs_array_states,
+							       sra->array_state);
 				else
 					arrayst = "clean";
 			} else {
diff --git a/Grow.c b/Grow.c
index 18c5719..8a242b0 100644
--- a/Grow.c
+++ b/Grow.c
@@ -547,7 +547,7 @@ int Grow_consistency_policy(char *devname, int fd, struct context *c, struct sha
 	if (s->consistency_policy != CONSISTENCY_POLICY_RESYNC &&
 	    s->consistency_policy != CONSISTENCY_POLICY_PPL) {
 		pr_err("Operation not supported for consistency policy %s\n",
-		       map_num(consistency_policies, s->consistency_policy));
+		       map_num_s(consistency_policies, s->consistency_policy));
 		return 1;
 	}
 
@@ -578,14 +578,14 @@ int Grow_consistency_policy(char *devname, int fd, struct context *c, struct sha
 
 	if (sra->consistency_policy == (unsigned)s->consistency_policy) {
 		pr_err("Consistency policy is already %s\n",
-		       map_num(consistency_policies, s->consistency_policy));
+		       map_num_s(consistency_policies, s->consistency_policy));
 		ret = 1;
 		goto free_info;
 	} else if (sra->consistency_policy != CONSISTENCY_POLICY_RESYNC &&
 		   sra->consistency_policy != CONSISTENCY_POLICY_PPL) {
 		pr_err("Current consistency policy is %s, cannot change to %s\n",
-		       map_num(consistency_policies, sra->consistency_policy),
-		       map_num(consistency_policies, s->consistency_policy));
+		       map_num_s(consistency_policies, sra->consistency_policy),
+		       map_num_s(consistency_policies, s->consistency_policy));
 		ret = 1;
 		goto free_info;
 	}
@@ -704,8 +704,8 @@ int Grow_consistency_policy(char *devname, int fd, struct context *c, struct sha
 	}
 
 	ret = sysfs_set_str(sra, NULL, "consistency_policy",
-			    map_num(consistency_policies,
-				    s->consistency_policy));
+			    map_num_s(consistency_policies,
+					 s->consistency_policy));
 	if (ret)
 		pr_err("Failed to change array consistency policy\n");
 
@@ -2241,7 +2241,7 @@ size_change_error:
 		info.new_layout = UnSet;
 		if (info.array.level == 6 && info.new_level == UnSet) {
 			char l[40], *h;
-			strcpy(l, map_num(r6layout, info.array.layout));
+			strcpy(l, map_num_s(r6layout, info.array.layout));
 			h = strrchr(l, '-');
 			if (h && strcmp(h, "-6") == 0) {
 				*h = 0;
@@ -2266,7 +2266,7 @@ size_change_error:
 			info.new_layout = info.array.layout;
 		else if (info.array.level == 5 && info.new_level == 6) {
 			char l[40];
-			strcpy(l, map_num(r5layout, info.array.layout));
+			strcpy(l, map_num_s(r5layout, info.array.layout));
 			strcat(l, "-6");
 			info.new_layout = map_name(r6layout, l);
 		} else {
diff --git a/Query.c b/Query.c
index 23fbf8a..adcd231 100644
--- a/Query.c
+++ b/Query.c
@@ -93,7 +93,7 @@ int Query(char *dev)
 	else {
 		printf("%s: %s %s %d devices, %d spare%s. Use mdadm --detail for more detail.\n",
 		       dev, human_size_brief(larray_size,IEC),
-		       map_num(pers, level), raid_disks,
+		       map_num_s(pers, level), raid_disks,
 		       spare_disks, spare_disks == 1 ? "" : "s");
 	}
 	st = guess_super(fd);
@@ -131,7 +131,7 @@ int Query(char *dev)
 		       dev,
 		       info.disk.number, info.array.raid_disks,
 		       activity,
-		       map_num(pers, info.array.level),
+		       map_num_s(pers, info.array.level),
 		       mddev);
 		if (st->ss == &super0)
 			put_md_name(mddev);
diff --git a/maps.c b/maps.c
index a4fd279..20fcf71 100644
--- a/maps.c
+++ b/maps.c
@@ -166,6 +166,30 @@ mapping_t sysfs_array_states[] = {
 	{ NULL, ARRAY_UNKNOWN_STATE }
 };
 
+/**
+ * map_num_s() - Safer alternative of map_num() function.
+ * @map: map to search.
+ * @num: key to match.
+ *
+ * Shall be used only if key existence is quaranted.
+ *
+ * Return: Pointer to name of the element.
+ */
+char *map_num_s(mapping_t *map, int num)
+{
+	char *ret = map_num(map, num);
+
+	assert(ret);
+	return ret;
+}
+
+/**
+ * map_num() - get element name by key.
+ * @map: map to search.
+ * @num: key to match.
+ *
+ * Return: Pointer to name of the element or NULL.
+ */
 char *map_num(mapping_t *map, int num)
 {
 	while (map->name) {
diff --git a/mdadm.c b/mdadm.c
index 26299b2..be40686 100644
--- a/mdadm.c
+++ b/mdadm.c
@@ -280,8 +280,8 @@ int main(int argc, char *argv[])
 			else
 				fprintf(stderr, "-%c", opt);
 			fprintf(stderr, " would set mdadm mode to \"%s\", but it is already set to \"%s\".\n",
-				map_num(modes, newmode),
-				map_num(modes, mode));
+				map_num_s(modes, newmode),
+				map_num_s(modes, mode));
 			exit(2);
 		} else if (!mode && newmode) {
 			mode = newmode;
@@ -544,7 +544,7 @@ int main(int argc, char *argv[])
 			switch(s.level) {
 			default:
 				pr_err("layout not meaningful for %s arrays.\n",
-					map_num(pers, s.level));
+					map_num_s(pers, s.level));
 				exit(2);
 			case UnSet:
 				pr_err("raid level must be given before layout.\n");
@@ -1248,10 +1248,10 @@ int main(int argc, char *argv[])
 		if (option_index > 0)
 			pr_err(":option --%s not valid in %s mode\n",
 				long_options[option_index].name,
-				map_num(modes, mode));
+				map_num_s(modes, mode));
 		else
 			pr_err("option -%c not valid in %s mode\n",
-				opt, map_num(modes, mode));
+				opt, map_num_s(modes, mode));
 		exit(2);
 
 	}
@@ -1276,7 +1276,7 @@ int main(int argc, char *argv[])
 		if (s.consistency_policy != CONSISTENCY_POLICY_UNKNOWN &&
 		    s.consistency_policy != CONSISTENCY_POLICY_JOURNAL) {
 			pr_err("--write-journal is not supported with consistency policy: %s\n",
-			       map_num(consistency_policies, s.consistency_policy));
+			       map_num_s(consistency_policies, s.consistency_policy));
 			exit(2);
 		}
 	}
@@ -1285,12 +1285,12 @@ int main(int argc, char *argv[])
 	    s.consistency_policy != CONSISTENCY_POLICY_UNKNOWN) {
 		if (s.level <= 0) {
 			pr_err("--consistency-policy not meaningful with level %s.\n",
-			       map_num(pers, s.level));
+			       map_num_s(pers, s.level));
 			exit(2);
 		} else if (s.consistency_policy == CONSISTENCY_POLICY_JOURNAL &&
 			   !s.journaldisks) {
 			pr_err("--write-journal is required for consistency policy: %s\n",
-			       map_num(consistency_policies, s.consistency_policy));
+			       map_num_s(consistency_policies, s.consistency_policy));
 			exit(2);
 		} else if (s.consistency_policy == CONSISTENCY_POLICY_PPL &&
 			   s.level != 5) {
@@ -1300,14 +1300,14 @@ int main(int argc, char *argv[])
 			   (!s.bitmap_file ||
 			    strcmp(s.bitmap_file, "none") == 0)) {
 			pr_err("--bitmap is required for consistency policy: %s\n",
-			       map_num(consistency_policies, s.consistency_policy));
+			       map_num_s(consistency_policies, s.consistency_policy));
 			exit(2);
 		} else if (s.bitmap_file &&
 			   strcmp(s.bitmap_file, "none") != 0 &&
 			   s.consistency_policy != CONSISTENCY_POLICY_BITMAP &&
 			   s.consistency_policy != CONSISTENCY_POLICY_JOURNAL) {
 			pr_err("--bitmap is not compatible with consistency policy: %s\n",
-			       map_num(consistency_policies, s.consistency_policy));
+			       map_num_s(consistency_policies, s.consistency_policy));
 			exit(2);
 		}
 	}
diff --git a/mdadm.h b/mdadm.h
index cd72e71..09915a0 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -770,7 +770,7 @@ extern int restore_stripes(int *dest, unsigned long long *offsets,
 #endif
 
 #define SYSLOG_FACILITY LOG_DAEMON
-
+extern char *map_num_s(mapping_t *map, int num);
 extern char *map_num(mapping_t *map, int num);
 extern int map_name(mapping_t *map, char *name);
 extern mapping_t r0layout[], r5layout[], r6layout[],
diff --git a/super-ddf.c b/super-ddf.c
index 3f304cd..8cda23a 100644
--- a/super-ddf.c
+++ b/super-ddf.c
@@ -1477,13 +1477,13 @@ static void examine_vds(struct ddf_super *sb)
 		printf("\n");
 		printf("         unit[%d] : %d\n", i, be16_to_cpu(ve->unit));
 		printf("        state[%d] : %s, %s%s\n", i,
-		       map_num(ddf_state, ve->state & 7),
+		       map_num_s(ddf_state, ve->state & 7),
 		       (ve->state & DDF_state_morphing) ? "Morphing, ": "",
 		       (ve->state & DDF_state_inconsistent)? "Not Consistent" : "Consistent");
 		printf("   init state[%d] : %s\n", i,
-		       map_num(ddf_init_state, ve->init_state&DDF_initstate_mask));
+		       map_num_s(ddf_init_state, ve->init_state & DDF_initstate_mask));
 		printf("       access[%d] : %s\n", i,
-		       map_num(ddf_access, (ve->init_state & DDF_access_mask) >> 6));
+		       map_num_s(ddf_access, (ve->init_state & DDF_access_mask) >> 6));
 		printf("         Name[%d] : %.16s\n", i, ve->name);
 		examine_vd(i, sb, ve->guid);
 	}
diff --git a/super-intel.c b/super-intel.c
index 6ff336e..ba3bd41 100644
--- a/super-intel.c
+++ b/super-intel.c
@@ -5625,7 +5625,7 @@ static int init_super_imsm_volume(struct supertype *st, mdu_array_info_t *info,
 		free(dev);
 		free(dv);
 		pr_err("imsm does not support consistency policy %s\n",
-		       map_num(consistency_policies, s->consistency_policy));
+		       map_num_s(consistency_policies, s->consistency_policy));
 		return 0;
 	}
 
diff --git a/super0.c b/super0.c
index b79b97a..61c9ec1 100644
--- a/super0.c
+++ b/super0.c
@@ -288,7 +288,7 @@ static void export_examine_super0(struct supertype *st)
 {
 	mdp_super_t *sb = st->sb;
 
-	printf("MD_LEVEL=%s\n", map_num(pers, sb->level));
+	printf("MD_LEVEL=%s\n", map_num_s(pers, sb->level));
 	printf("MD_DEVICES=%d\n", sb->raid_disks);
 	if (sb->minor_version >= 90)
 		printf("MD_UUID=%08x:%08x:%08x:%08x\n",
diff --git a/super1.c b/super1.c
index a12a5bc..e3e2f95 100644
--- a/super1.c
+++ b/super1.c
@@ -671,7 +671,7 @@ static void export_examine_super1(struct supertype *st)
 	int len = 32;
 	int layout;
 
-	printf("MD_LEVEL=%s\n", map_num(pers, __le32_to_cpu(sb->level)));
+	printf("MD_LEVEL=%s\n", map_num_s(pers, __le32_to_cpu(sb->level)));
 	printf("MD_DEVICES=%d\n", __le32_to_cpu(sb->raid_disks));
 	for (i = 0; i < 32; i++)
 		if (sb->set_name[i] == '\n' || sb->set_name[i] == '\0') {
diff --git a/sysfs.c b/sysfs.c
index 2995713..0d98a65 100644
--- a/sysfs.c
+++ b/sysfs.c
@@ -689,7 +689,7 @@ int sysfs_set_array(struct mdinfo *info, int vers)
 	if (info->array.level < 0)
 		return 0; /* FIXME */
 	rv |= sysfs_set_str(info, NULL, "level",
-			    map_num(pers, info->array.level));
+			    map_num_s(pers, info->array.level));
 	if (info->reshape_active && info->delta_disks != UnSet)
 		raid_disks -= info->delta_disks;
 	rv |= sysfs_set_num(info, NULL, "raid_disks", raid_disks);
@@ -724,9 +724,10 @@ int sysfs_set_array(struct mdinfo *info, int vers)
 	}
 
 	if (info->consistency_policy == CONSISTENCY_POLICY_PPL) {
-		if (sysfs_set_str(info, NULL, "consistency_policy",
-				  map_num(consistency_policies,
-					  info->consistency_policy))) {
+		char *policy = map_num_s(consistency_policies,
+					    info->consistency_policy);
+
+		if (sysfs_set_str(info, NULL, "consistency_policy", policy)) {
 			pr_err("This kernel does not support PPL. Falling back to consistency-policy=resync.\n");
 			info->consistency_policy = CONSISTENCY_POLICY_RESYNC;
 		}