CVE-2024-35952 Information

Description

In the Linux kernel the following vulnerability has been resolved:

drm/ast: Fix soft lockup

There is a while-loop in ast_dp_set_on_off() that could lead to infinite-loop. This is because the register VGACRI-Dx checked in this API is a scratch register actually controlled by a MCU named DPMCU in BMC.

These scratch registers are protected by scu-lock. If suc-lock is not off DPMCU can not update these registers and then host will have soft lockup due to never updated status.

DPMCU is used to control DP and relative registers to handshake with host’s VGA driver. Even the most time-consuming task DP’s link training is less than 100ms. 200ms should be enough.

Reference

https://git.kernel.org/stable/c/8a6fea3fcb577a543ef67683ca7105bde49a38fb https://git.kernel.org/stable/c/a81b2acd43e24e419f65df97348c76a5a1496066 https://git.kernel.org/stable/c/35768baf0fdfc47ede42d899506bad78450e9294 https://git.kernel.org/stable/c/bc004f5038220b1891ef4107134ccae44be55109