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>] [day] [month] [year] [list]
Date:   Mon, 24 Aug 2020 12:36:05 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Oleksij Rempel <o.rempel@...gutronix.de>,
        Marc Kleine-Budde <mkl@...gutronix.de>,
        Sasha Levin <sashal@...nel.org>, linux-can@...r.kernel.org,
        netdev@...r.kernel.org
Subject: [PATCH AUTOSEL 5.7 26/54] can: j1939: transport: j1939_xtp_rx_dat_one(): compare own packets to detect corruptions

From: Oleksij Rempel <o.rempel@...gutronix.de>

[ Upstream commit e052d0540298bfe0f6cbbecdc7e2ea9b859575b2 ]

Since the stack relays on receiving own packets, it was overwriting own
transmit buffer from received packets.

At least theoretically, the received echo buffer can be corrupt or
changed and the session partner can request to resend previous data. In
this case we will re-send bad data.

With this patch we will stop to overwrite own TX buffer and use it for
sanity checking.

Signed-off-by: Oleksij Rempel <o.rempel@...gutronix.de>
Link: https://lore.kernel.org/r/20200807105200.26441-6-o.rempel@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@...gutronix.de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 net/can/j1939/transport.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 9f99af5b0b11e..3e9c377b0dcce 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -1769,7 +1769,20 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
 	}
 
 	tpdat = se_skb->data;
-	memcpy(&tpdat[offset], &dat[1], nbytes);
+	if (!session->transmission) {
+		memcpy(&tpdat[offset], &dat[1], nbytes);
+	} else {
+		int err;
+
+		err = memcmp(&tpdat[offset], &dat[1], nbytes);
+		if (err)
+			netdev_err_once(priv->ndev,
+					"%s: 0x%p: Data of RX-looped back packet (%*ph) doesn't match TX data (%*ph)!\n",
+					__func__, session,
+					nbytes, &dat[1],
+					nbytes, &tpdat[offset]);
+	}
+
 	if (packet == session->pkt.rx)
 		session->pkt.rx++;
 
-- 
2.25.1

Powered by blists - more mailing lists