diff --git a/klibc_fixups.c b/klibc_fixups.c
index 1241eb7d108..99460c32f71 100644
--- a/klibc_fixups.c
+++ b/klibc_fixups.c
@@ -74,7 +74,7 @@ static unsigned long get_id_by_name(const char *uname, const char *dbfile)
 
 		if (strcmp(uname, name) == 0) {
 			id = strtoul(idstr, &tail, 10);
-			if (tail == NULL)
+			if (tail[0] != '\0')
 				id = -1;
 			else
 				dbg("id for '%s' is '%li'", name, id);
diff --git a/namedev.c b/namedev.c
index 2ebf276f6b9..ed8d6c1808b 100644
--- a/namedev.c
+++ b/namedev.c
@@ -198,7 +198,7 @@ static int get_format_len(char **str)
 
 	if (isdigit(*str[0])) {
 		num = (int) strtoul(*str, &tail, 10);
-		if (tail != NULL) {
+		if (num > 0) {
 			*str = tail;
 			dbg("format length=%i", num);
 			return num;