From: Szymon Heidrich szymon.heidrich@gmail.com
[ Upstream commit ff821092cf02a70c2bccd2d19269f01e29aa52cf ]
Packet length retrieved from descriptor may be larger than the actual socket buffer length. In such case the cloned skb passed up the network stack will leak kernel memory contents.
Fixes: 2f7ca802bdae ("net: Add SMSC LAN9500 USB2.0 10/100 ethernet adapter driver") Signed-off-by: Szymon Heidrich szymon.heidrich@gmail.com Reviewed-by: Jakub Kicinski kuba@kernel.org Link: https://lore.kernel.org/r/20230316101954.75836-1-szymon.heidrich@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/usb/smsc95xx.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index 4f29010e1aeff..0850486864135 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -1950,6 +1950,12 @@ static int smsc95xx_rx_fixup(struct usbnet *dev, struct sk_buff *skb) size = (u16)((header & RX_STS_FL_) >> 16); align_count = (4 - ((size + NET_IP_ALIGN) % 4)) % 4;
+ if (unlikely(size > skb->len)) { + netif_dbg(dev, rx_err, dev->net, + "size err header=0x%08x\n", header); + return 0; + } + if (unlikely(header & RX_STS_ES_)) { netif_dbg(dev, rx_err, dev->net, "Error header=0x%08x\n", header);