netdev - [PATCH net-next 43/47] can: bittiming: can_sjw_check(): check that SJW is not longer than either Phase Buffer Segment

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: <20230206131620.2758724-44-mkl@pengutronix.de>
Date:   Mon,  6 Feb 2023 14:16:16 +0100
From:   Marc Kleine-Budde <mkl@...gutronix.de>
To:     netdev@...r.kernel.org
Cc:     davem@...emloft.net, kuba@...nel.org, linux-can@...r.kernel.org,
        kernel@...gutronix.de, Marc Kleine-Budde <mkl@...gutronix.de>,
        Vincent Mailhol <vincent.mailhol@...il.com>
Subject: [PATCH net-next 43/47] can: bittiming: can_sjw_check(): check that SJW is not longer than either Phase Buffer Segment

According to "The Configuration of the CAN Bit Timing" [1] the SJW
"may not be longer than either Phase Buffer Segment".

Check SJW against length of both Phase buffers. In case the SJW is
greater, report an error via netlink to user space and bail out.

[1] http://web.archive.org/http://www.oertel-halle.de/files/cia99paper.pdf

Link: https://lore.kernel.org/all/20230202110854.2318594-14-mkl@pengutronix.de
Suggested-by: Vincent Mailhol <vincent.mailhol@...il.com>
Signed-off-by: Marc Kleine-Budde <mkl@...gutronix.de>
---
 drivers/net/can/dev/bittiming.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/net/can/dev/bittiming.c b/drivers/net/can/dev/bittiming.c
index 0a2a9b12565f..68287b79afe8 100644
--- a/drivers/net/can/dev/bittiming.c
+++ b/drivers/net/can/dev/bittiming.c
@@ -24,6 +24,20 @@ int can_sjw_check(const struct net_device *dev, const struct can_bittiming *bt,
 		return -EINVAL;
 	}
 
+	if (bt->sjw > bt->phase_seg1) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "sjw: %u greater than phase-seg1: %u",
+				   bt->sjw, bt->phase_seg1);
+		return -EINVAL;
+	}
+
+	if (bt->sjw > bt->phase_seg2) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "sjw: %u greater than phase-seg2: %u",
+				   bt->sjw, bt->phase_seg2);
+		return -EINVAL;
+	}
+
 	return 0;
 }
 
-- 
2.39.1