netdev - [PATCH net] net: mvneta: fix potential double-frees in mvneta_txq_sw

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]

Message-Id: <E1phUe5-00EieL-7q@rmk-PC.armlinux.org.uk>
Date:   Wed, 29 Mar 2023 13:11:17 +0100
From:   "Russell King (Oracle)" <rmk+kernel@...linux.org.uk>
To:     Andrew Lunn <andrew@...n.ch>,
        Heiner Kallweit <hkallweit1@...il.com>
Cc:     Marek Beh__n <kabel@...nel.org>,
        Thomas Petazzoni <thomas.petazzoni@...tlin.com>,
        "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>, netdev@...r.kernel.org
Subject: [PATCH net] net: mvneta: fix potential double-frees in
 mvneta_txq_sw_deinit()

Reported on the Turris forum, mvneta provokes kernel warnings in the
architecture DMA mapping code when mvneta_setup_txqs() fails to
allocate memory. This happens because when mvneta_cleanup_txqs() is
called in the mvneta_stop() path, we leave pointers in the structure
that have been freed.

Then on mvneta_open(), we call mvneta_setup_txqs(), which starts
allocating memory. On memory allocation failure, mvneta_cleanup_txqs()
will walk all the queues freeing any non-NULL pointers - which includes
pointers that were previously freed in mvneta_stop().

Fix this by setting these pointers to NULL to prevent double-freeing
of the same memory.

Link: https://forum.turris.cz/t/random-kernel-exceptions-on-hbl-tos-7-0/18865/8
Signed-off-by: Russell King (Oracle) <rmk+kernel@...linux.org.uk>
---
 drivers/net/ethernet/marvell/mvneta.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 0e39d199ff06..2cad76d0a50e 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -3549,6 +3549,8 @@ static void mvneta_txq_sw_deinit(struct mvneta_port *pp,

 	netdev_tx_reset_queue(nq);

+	txq->buf               = NULL;
+	txq->tso_hdrs          = NULL;
 	txq->descs             = NULL;
 	txq->last_desc         = 0;
 	txq->next_desc_to_proc = 0;
-- 
2.30.2