linux-kernel - [PATCH 3/4] net: ll_temac: Fix TX BD buffer overwrite

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

Message-Id: <af756a6fda027c300f38f73cad133450f7dd1636.1624013456.git.esben@geanix.com>
Date:   Fri, 18 Jun 2021 12:52:33 +0200
From:   Esben Haabendal <esben@...nix.com>
To:     netdev@...r.kernel.org
Cc:     stable@...r.kernel.org, "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Michal Simek <michal.simek@...inx.com>,
        Zhang Changzhong <zhangchangzhong@...wei.com>,
        Jesse Brandeburg <jesse.brandeburg@...el.com>,
        Andrew Lunn <andrew@...n.ch>, Wang Hai <wanghai38@...wei.com>,
        Michael Walle <michael@...le.cc>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [PATCH 3/4] net: ll_temac: Fix TX BD buffer overwrite

Just as the initial check, we need to ensure num_frag+1 buffers available,
as that is the number of buffers we are going to use.

This fixes a buffer overflow, which might be seen during heavy network
load. Complete lockup of TEMAC was reproducible within about 10 minutes of
a particular load.

Fixes: 84823ff80f74 ("net: ll_temac: Fix race condition causing TX hang")
Cc: stable@...r.kernel.org # v5.4+
Signed-off-by: Esben Haabendal <esben@...nix.com>
---
 drivers/net/ethernet/xilinx/ll_temac_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c
index 9797aa3221d1..cc482ee36501 100644
--- a/drivers/net/ethernet/xilinx/ll_temac_main.c
+++ b/drivers/net/ethernet/xilinx/ll_temac_main.c
@@ -861,7 +861,7 @@ temac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 		smp_mb();
 
 		/* Space might have just been freed - check again */
-		if (temac_check_tx_bd_space(lp, num_frag))
+		if (temac_check_tx_bd_space(lp, num_frag + 1))
 			return NETDEV_TX_BUSY;
 
 		netif_wake_queue(ndev);
-- 
2.32.0