CVE-2026-31729

In the Linux kernel, the following vulnerability has been resolved:

usb: typec: ucsi: validate connector number in ucsinotifycommon()

The connector number extracted from CCI via UCSICCICONNECTOR() is a 7-bit field (0-127) that is used to index into the connector array in ucsiconnectorchange(). However, the array is only allocated for the number of connectors reported by the device (typically 2-4 entries).

A malicious or malfunctioning device could report an out-of-range connector number in the CCI, causing an out-of-bounds array access in ucsiconnectorchange().

Add a bounds check in ucsinotifycommon(), the central point where CCI is parsed after arriving from hardware, so that bogus connector numbers are rejected before they propagate further.