This is a note to let you know that I've just added the patch titled net: usb: sr9700: Handle negative len to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-usb-sr9700-handle-negative-len.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0578fbb6db93ba80a15a9f6ae9fef50850ff51c4 Author: Szymon Heidrich <szymon.heidrich@xxxxxxxxx> Date: Sat Jan 14 19:23:26 2023 +0100 net: usb: sr9700: Handle negative len [ Upstream commit ecf7cf8efb59789e2b21d2f9ab926142579092b2 ] Packet len computed as difference of length word extracted from skb data and four may result in a negative value. In such case processing of the buffer should be interrupted rather than setting sr_skb->len to an unexpectedly large value (due to cast from signed to unsigned integer) and passing sr_skb to usbnet_skb_return. Fixes: e9da0b56fe27 ("sr9700: sanity check for packet length") Signed-off-by: Szymon Heidrich <szymon.heidrich@xxxxxxxxx> Link: https://lore.kernel.org/r/20230114182326.30479-1-szymon.heidrich@xxxxxxxxx Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c index 83640628c47d..8bee8286e41a 100644 --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -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 || len > skb->len) + if (len > ETH_FRAME_LEN || len > skb->len || len < 0) return 0; /* the last packet of current skb */