can: peak_usb: fix use after free bugs

After calling peak_usb_netif_rx_ni(skb), dereferencing skb is unsafe.
Especially, the can_frame cf which aliases skb memory is accessed
after the peak_usb_netif_rx_ni().

Reordering the lines solves the issue.

Fixes: 0a25e1f4f1 ("can: peak_usb: add support for PEAK new CANFD USB adapters")
Link: https://lore.kernel.org/r/20210120114137.200019-4-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Vincent Mailhol 2021-01-20 20:41:37 +09:00 committed by Marc Kleine-Budde
parent 75854cad5d
commit 50aca891d7

View File

@ -514,11 +514,11 @@ static int pcan_usb_fd_decode_canmsg(struct pcan_usb_fd_if *usb_if,
else
memcpy(cfd->data, rm->d, cfd->len);
peak_usb_netif_rx(skb, &usb_if->time_ref, le32_to_cpu(rm->ts_low));
netdev->stats.rx_packets++;
netdev->stats.rx_bytes += cfd->len;
peak_usb_netif_rx(skb, &usb_if->time_ref, le32_to_cpu(rm->ts_low));
return 0;
}
@ -580,11 +580,11 @@ static int pcan_usb_fd_decode_status(struct pcan_usb_fd_if *usb_if,
if (!skb)
return -ENOMEM;
peak_usb_netif_rx(skb, &usb_if->time_ref, le32_to_cpu(sm->ts_low));
netdev->stats.rx_packets++;
netdev->stats.rx_bytes += cf->len;
peak_usb_netif_rx(skb, &usb_if->time_ref, le32_to_cpu(sm->ts_low));
return 0;
}