Commit ecf7cf8e authored by Szymon Heidrich's avatar Szymon Heidrich Committed by Paolo Abeni
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net: usb: sr9700: Handle negative len 



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: e9da0b56 ("sr9700: sanity check for packet length")
Signed-off-by: default avatarSzymon Heidrich <szymon.heidrich@gmail.com>
Link: https://lore.kernel.org/r/20230114182326.30479-1-szymon.heidrich@gmail.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 87b93b67

drivers/net/usb/sr9700.c

+1 −1
Original line number Diff line number Diff line
@@ -413,7 +413,7 @@ 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 */