Anssi Hannula 0f8c88978d can: kvaser_usb_leaf: Fix overread with an invalid command
commit 1499ecaea9d2ba68d5e18d80573b4561a8dc4ee7 upstream.

For command events read from the device,
kvaser_usb_leaf_read_bulk_callback() verifies that cmd->len does not
exceed the size of the received data, but the actual kvaser_cmd handlers
will happily read any kvaser_cmd fields without checking for cmd->len.

This can cause an overread if the last cmd in the buffer is shorter than
expected for the command type (with cmd->len showing the actual short
size).

Maximum overread seems to be 22 bytes (CMD_LEAF_LOG_MESSAGE), some of
which are delivered to userspace as-is.

Fix that by verifying the length of command before handling it.

This issue can only occur after RX URBs have been set up, i.e. the
interface has been opened at least once.

Cc: stable@vger.kernel.org
Fixes: 080f40a6fa28 ("can: kvaser_usb: Add support for Kvaser CAN/USB devices")
Tested-by: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://lore.kernel.org/all/20221010150829.199676-2-extja@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 13:25:08 +02:00
2020-10-17 11:18:18 -07:00
2022-10-17 17:26:07 +02:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 5.7 GiB
Languages
C 97.6%
Assembly 1%
Shell 0.5%
Python 0.3%
Makefile 0.3%