diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index dce0a6e..44a0d9b 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -897,7 +897,7 @@
 {
 	struct seq_file *m = file->private_data;
 	struct acpi_video_device *dev = m->private;
-	char str[4] = { 0 };
+	char str[5] = { 0 };
 	unsigned int level = 0;
 	int i;