netdev - [PATCH net-next 2/3] mctp i2c: Fix potential use-after-free

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Date:   Fri, 25 Feb 2022 13:39:37 +0800
From:   Matt Johnston <matt@...econstruct.com.au>
To:     netdev@...r.kernel.org
Cc:     "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Jeremy Kerr <jk@...econstruct.com.au>,
        Dan Carpenter <dan.carpenter@...cle.com>
Subject: [PATCH net-next 2/3] mctp i2c: Fix potential use-after-free

The skb is handed off to netif_rx() which may free it.
Found by Smatch.

Reported-By: Dan Carpenter <dan.carpenter@...cle.com>
Signed-off-by: Matt Johnston <matt@...econstruct.com.au>
---
 drivers/net/mctp/mctp-i2c.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/mctp/mctp-i2c.c b/drivers/net/mctp/mctp-i2c.c
index 365c3dfd4034..470682c88d7e 100644
--- a/drivers/net/mctp/mctp-i2c.c
+++ b/drivers/net/mctp/mctp-i2c.c
@@ -338,7 +338,7 @@ static int mctp_i2c_recv(struct mctp_i2c_dev *midev)
 
 	if (status == NET_RX_SUCCESS) {
 		ndev->stats.rx_packets++;
-		ndev->stats.rx_bytes += skb->len;
+		ndev->stats.rx_bytes += recvlen;
 	} else {
 		ndev->stats.rx_dropped++;
 	}
-- 
2.32.0