diff --git a/bin/df/df.c b/bin/df/df.c
index 77c2d28efe70..f244c26f8767 100644
--- a/bin/df/df.c
+++ b/bin/df/df.c
@@ -548,8 +548,10 @@ makenetvfslist()
 			}
 		}
 
-	if ((str = malloc(sizeof(char) * (32 * cnt + cnt + 2))) == NULL) {
-		warnx("malloc failed");
+	if (cnt == 0 ||
+	    (str = malloc(sizeof(char) * (32 * cnt + cnt + 2))) == NULL) {
+		if (cnt > 0)
+			warnx("malloc failed");
 		free(listptr);
 		return (NULL);
 	}