From: Szymon Heidrich szymon.heidrich@gmail.com
[ 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@gmail.com Link: https://lore.kernel.org/r/20230114182326.30479-1-szymon.heidrich@gmail.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/usb/sr9700.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c index fce6713e970b..811c8751308c 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 */