diff --git a/conf.c b/conf.c
index fdeb9db..3998bfa 100644
--- a/conf.c
+++ b/conf.c
@@ -401,9 +401,9 @@ static void get_dns(struct ctx *c)
 	struct fqdn *s = c->dns_search;
 	struct lineread resolvconf;
 	unsigned int added = 0;
+	ssize_t line_len;
 	char *line, *end;
 	const char *p;
-	int line_len;
 
 	dns4_set = !c->ifi4 || !IN4_IS_ADDR_UNSPECIFIED(dns4);
 	dns6_set = !c->ifi6 || !IN6_IS_ADDR_UNSPECIFIED(dns6);
diff --git a/lineread.c b/lineread.c
index d631da4..0387f4a 100644
--- a/lineread.c
+++ b/lineread.c
@@ -39,13 +39,11 @@ void lineread_init(struct lineread *lr, int fd)
  *
  * Return: length of line in bytes, -1 if no line was found
  */
-static int peek_line(struct lineread *lr, bool eof)
+static ssize_t peek_line(struct lineread *lr, bool eof)
 {
 	char *nl;
 
 	/* Sanity checks (which also document invariants) */
-	ASSERT(lr->count >= 0);
-	ASSERT(lr->next_line >= 0);
 	ASSERT(lr->next_line + lr->count >= lr->next_line);
 	ASSERT(lr->next_line + lr->count <= LINEREAD_BUFFER_SIZE);
 
@@ -74,13 +72,13 @@ static int peek_line(struct lineread *lr, bool eof)
  *
  * Return:	Length of line read on success, 0 on EOF, negative on error
  */
-int lineread_get(struct lineread *lr, char **line)
+ssize_t lineread_get(struct lineread *lr, char **line)
 {
 	bool eof = false;
-	int line_len;
+	ssize_t line_len;
 
 	while ((line_len = peek_line(lr, eof)) < 0) {
-		int rc;
+		ssize_t rc;
 
 		if ((lr->next_line + lr->count) == LINEREAD_BUFFER_SIZE) {
 			/* No space at end */
diff --git a/lineread.h b/lineread.h
index af86418..9203e28 100644
--- a/lineread.h
+++ b/lineread.h
@@ -18,14 +18,15 @@
  * @buf:	Buffer storing data read from file.
  */
 struct lineread {
-	int fd; int next_line;
-	int count;
+	int fd;
+	ssize_t next_line;
+	ssize_t count;
 
 	/* One extra byte for possible trailing \0 */
 	char buf[LINEREAD_BUFFER_SIZE+1];
 };
 
 void lineread_init(struct lineread *lr, int fd);
-int lineread_get(struct lineread *lr, char **line);
+ssize_t lineread_get(struct lineread *lr, char **line);
 
 #endif /* _LINEREAD_H */