sr9700: sanity check for packet length

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@suse.com>
Reviewed-by: Grant Grundler <grundler@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Oliver Neukum 2022-02-17 14:10:44 +01:00 committed by Greg Kroah-Hartman
parent d0dac454b9
commit b95d71abeb

View File

@ -410,7 +410,7 @@ static int sr9700_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
/* 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 */