From: Oliver Neukum <oneukum@xxxxxxxx> commit e9da0b56fe27206b49f39805f7dcda8a89379062 upstream. A malicious device can leak heap data to user space providing bogus frame lengths. Introduce a sanity check. Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx> Reviewed-by: Grant Grundler <grundler@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/usb/sr9700.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -410,7 +410,7 @@ static int sr9700_rx_fixup(struct usbnet /* ignore the CRC length */ len = (skb->data[1] | (skb->data[2] << 8)) - 4; - if (len > ETH_FRAME_LEN) + if (len > ETH_FRAME_LEN || len > skb->len) return 0; /* the last packet of current skb */
