diff mbox series

can: pch_can: pch_can_rx_normal: fix use after free

Message ID 20211123111654.621610-1-mailhol.vincent@wanadoo.fr (mailing list archive)
State Awaiting Upstream
Delegated to: Netdev Maintainers
Headers show
Series can: pch_can: pch_can_rx_normal: fix use after free | expand

Checks

Context Check Description
netdev/tree_selection success Series ignored based on subject

Commit Message

Vincent Mailhol Nov. 23, 2021, 11:16 a.m. UTC
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.")
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
---
 drivers/net/can/pch_can.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c
index 92a54a5fd4c5..964c8a09226a 100644
--- a/drivers/net/can/pch_can.c
+++ b/drivers/net/can/pch_can.c
@@ -692,11 +692,11 @@  static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
 			cf->data[i + 1] = data_reg >> 8;
 		}
 
-		netif_receive_skb(skb);
 		rcv_pkts++;
 		stats->rx_packets++;
 		quota--;
 		stats->rx_bytes += cf->len;
+		netif_receive_skb(skb);
 
 		pch_fifo_thresh(priv, obj_num);
 		obj_num++;