| From 94cddf1e9227a171b27292509d59691819c458db Mon Sep 17 00:00:00 2001 |
| From: Vincent Mailhol <mailhol.vincent@wanadoo.fr> |
| Date: Tue, 23 Nov 2021 20:16:54 +0900 |
| Subject: can: pch_can: pch_can_rx_normal: fix use after free |
| |
| From: Vincent Mailhol <mailhol.vincent@wanadoo.fr> |
| |
| commit 94cddf1e9227a171b27292509d59691819c458db upstream. |
| |
| After calling netif_receive_skb(skb), dereferencing skb is unsafe. |
| Especially, the can_frame cf which aliases skb memory is dereferenced |
| just after the call netif_receive_skb(skb). |
| |
| Reordering the lines solves the issue. |
| |
| Fixes: b21d18b51b31 ("can: Topcliff: Add PCH_CAN driver.") |
| Link: https://lore.kernel.org/all/20211123111654.621610-1-mailhol.vincent@wanadoo.fr |
| Cc: stable@vger.kernel.org |
| Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> |
| Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/net/can/pch_can.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/drivers/net/can/pch_can.c |
| +++ b/drivers/net/can/pch_can.c |
| @@ -703,11 +703,11 @@ static int pch_can_rx_normal(struct net_ |
| cf->data[i + 1] = data_reg >> 8; |
| } |
| |
| - netif_receive_skb(skb); |
| rcv_pkts++; |
| stats->rx_packets++; |
| quota--; |
| stats->rx_bytes += cf->can_dlc; |
| + netif_receive_skb(skb); |
| |
| pch_fifo_thresh(priv, obj_num); |
| obj_num++; |