In the Linux kernel, the following vulnerability has been resolved:
riscv: Fix loading 64-bit NOMMU kernels past the start of RAM
commit 3335068f8721 ("riscv: Use PUD/P4D/PGD pages for the linear mapping") added logic to allow using RAM below the kernel load address. However, this does not work for NOMMU, where PAGEOFFSET is fixed to the kernel load address. Since that range of memory corresponds to PFNs below ARCHPFNOFFSET, mm initialization runs off the beginning of memmap and corrupts adjacent kernel memory. Fix this by restoring the previous behavior for NOMMU kernels.