[net 3/3] can: peak_usb: fix use after free bugs
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: 2021-01-20 20:26:09
Also in:
netdev
Subsystem:
can network drivers, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Linus Torvalds
From: Vincent Mailhol <redacted>
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: 0a25e1f4f185 ("can: peak_usb: add support for PEAK new CANFD USB adapters")
Link: https://lore.kernel.org/r/20210120114137.200019-4-mailhol.vincent@wanadoo.fr (local)
Signed-off-by: Vincent Mailhol <redacted>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
drivers/net/can/usb/peak_usb/pcan_usb_fd.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_fd.c b/drivers/net/can/usb/peak_usb/pcan_usb_fd.c
index 61631f4fd92a..f347ecc79aef 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb_fd.c
+++ b/drivers/net/can/usb/peak_usb/pcan_usb_fd.c@@ -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; }
--
2.29.2