netdev - [PATCH net-next] net: dm9051: Fix use after free in dm9051_loop

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 18 Feb 2022 18:27:30 +0300
From:   Dan Carpenter <dan.carpenter@...cle.com>
To:     "David S. Miller" <davem@...emloft.net>,
        Joseph CHAMG <josright123@...il.com>
Cc:     Jakub Kicinski <kuba@...nel.org>, netdev@...r.kernel.org,
        kernel-janitors@...r.kernel.org
Subject: [PATCH net-next] net: dm9051: Fix use after free in dm9051_loop_tx()

This code dereferences "skb" after calling dev_kfree_skb().

Fixes: 2dc95a4d30ed ("net: Add dm9051 driver")
Signed-off-by: Dan Carpenter <dan.carpenter@...cle.com>
---
 drivers/net/ethernet/davicom/dm9051.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/davicom/dm9051.c b/drivers/net/ethernet/davicom/dm9051.c
index a63d17e669a0..f6b5d2becf5e 100644
--- a/drivers/net/ethernet/davicom/dm9051.c
+++ b/drivers/net/ethernet/davicom/dm9051.c
@@ -850,13 +850,13 @@ static int dm9051_loop_tx(struct board_info *db)
 		if (skb) {
 			ntx++;
 			ret = dm9051_single_tx(db, skb->data, skb->len);
+			ndev->stats.tx_bytes += skb->len;
+			ndev->stats.tx_packets++;
 			dev_kfree_skb(skb);
 			if (ret < 0) {
 				db->bc.tx_err_counter++;
 				return 0;
 			}
-			ndev->stats.tx_bytes += skb->len;
-			ndev->stats.tx_packets++;
 		}
 
 		if (netif_queue_stopped(ndev) &&
-- 
2.20.1