diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c
index d8ac0ce2d6bfcb90e49ac8f611cac6aa3c73d4c1..f7559bfeaba3c86a0b72c184012a428fc46d2319 100644
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -563,6 +563,10 @@ static int init_request(struct client *client,
 	    (request->length > 4096 || request->length > 512 << speed))
 		return -EIO;
 
+	if (request->tcode == TCODE_WRITE_QUADLET_REQUEST &&
+	    request->length < 4)
+		return -EINVAL;
+
 	e = kmalloc(sizeof(*e) + request->length, GFP_KERNEL);
 	if (e == NULL)
 		return -ENOMEM;