An issue was discovered in aspeed_lpc_ctrl_mmap in
drivers/soc/aspeed/aspeed-lpc-ctrl.c in the Linux kernel before 5.14.6.
Local attackers able to access the Aspeed LPC control interface could
overwrite memory in the kernel and potentially execute privileges, aka
CID-b49a0e69a7b1. This occurs because a certain comparison uses values that
are not memory sizes.

It was discovered that the Aspeed Low Pin Count (LPC) Bus Controller
implementation in the Linux kernel did not properly perform boundary checks
in some situations, allowing out-of-bounds write access. A local attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. In Ubuntu, this issue only affected systems running
armhf kernels.

sbeattie

CONFIG_ASPEED_LPC_CTRL is only enabled on armhf platforms in Ubuntu