CVE-2025-68308

can: kvaser_usb: leaf: Fix potential infinite loop in command parsers

In the Linux kernel, the following vulnerability has been resolved: can: kvaser_usb: leaf: Fix potential infinite loop in command parsers The `kvaser_usb_leaf_wait_cmd()` and `kvaser_usb_leaf_read_bulk_callback` functions contain logic to zero-length commands. These commands are used to align data to the USB endpoint's wMaxPacketSize boundary. The driver attempts to skip these placeholders by aligning the buffer position `pos` to the next packet boundary using `round_up()` function. However, if zero-length command is found exactly on a packet boundary (i.e., `pos` is a multiple of wMaxPacketSize, including 0), `round_up` function will return the unchanged value of `pos`. This prevents `pos` to be increased, causing an infinite loop in the parsing logic. This patch fixes this in the function by using `pos + 1` instead. This ensures that even if `pos` is on a boundary, the calculation is based on `pos + 1`, forcing `round_up()` to always return the next aligned boundary.

Affected Versions

References