CVE-2026-99118

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

drm/i915/dmc: Harden DMC firmware payload parsing

Validate the conversion of the DMC firmware size from dwords to bytes using check_mul_overflow() before calculating the firmware payload size.

Reject zero-length payloads and zero MMIO counts in the DMC firmware header so malformed firmware is caught early. Also set dmc_fw_size only after the payload allocation succeeds.

(cherry picked from commit efde6601a1f1daedfe3dcc2816c934ddb44e3eef)