During the handling of CAN bus errors, a CAN error SKB is allocated using alloc_can_err_skb(). Even if the allocation of the SKB fails, the function continues in order to do the stats handling. All access to the can_frame pointer (cf) should be guarded by an if statement: if (cf) However, the increment of the rx_bytes stats: netdev->stats.rx_bytes += cf->can_dlc; dereferences the cf pointer and was not guarded by an if condition leading to a NULL pointer dereference if the can_err_skb() function failed. Replacing the cf->can_dlc by the macro CAN_ERR_DLC (which is the length of any CAN error frames) solves this NULL pointer dereference. Fixes: 8537257874e9 ("can: etas_es58x: add core support for ETAS ES58X CAN USB interfaces") Link: https://lore.kernel.org/r/20210413114242.2760-1-mailhol.vincent@wanadoo.fr Reported-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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
Languages
C
97.6%
Assembly
1%
Shell
0.5%
Python
0.3%
Makefile
0.3%