diff --git a/mailinfo.c b/mailinfo.c
index 5681d9130db..95ce191f385 100644
--- a/mailinfo.c
+++ b/mailinfo.c
@@ -821,7 +821,7 @@ static int handle_commit_msg(struct mailinfo *mi, struct strbuf *line)
 		for (i = 0; header[i]; i++) {
 			if (mi->s_hdr_data[i])
 				strbuf_release(mi->s_hdr_data[i]);
-			mi->s_hdr_data[i] = NULL;
+			FREE_AND_NULL(mi->s_hdr_data[i]);
 		}
 		return 0;
 	}
@@ -1236,22 +1236,14 @@ void setup_mailinfo(struct mailinfo *mi)
 
 void clear_mailinfo(struct mailinfo *mi)
 {
-	int i;
-
 	strbuf_release(&mi->name);
 	strbuf_release(&mi->email);
 	strbuf_release(&mi->charset);
 	strbuf_release(&mi->inbody_header_accum);
 	free(mi->message_id);
 
-	if (mi->p_hdr_data)
-		for (i = 0; mi->p_hdr_data[i]; i++)
-			strbuf_release(mi->p_hdr_data[i]);
-	free(mi->p_hdr_data);
-	if (mi->s_hdr_data)
-		for (i = 0; mi->s_hdr_data[i]; i++)
-			strbuf_release(mi->s_hdr_data[i]);
-	free(mi->s_hdr_data);
+	strbuf_list_free(mi->p_hdr_data);
+	strbuf_list_free(mi->s_hdr_data);
 
 	while (mi->content < mi->content_top) {
 		free(*(mi->content_top));
diff --git a/strbuf.c b/strbuf.c
index e3397cc4c72..4df30b45494 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -209,6 +209,8 @@ void strbuf_list_free(struct strbuf **sbs)
 {
 	struct strbuf **s = sbs;
 
+	if (!s)
+		return;
 	while (*s) {
 		strbuf_release(*s);
 		free(*s++);