Subject: CVE-2024-26795: riscv: Sparse-Memory/vmemmap out-of-bounds fix

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

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

riscv: Sparse-Memory/vmemmap out-of-bounds fix

Offset vmemmap so that the first page of vmemmap will be mapped
to the first page of physical memory in order to ensure that
vmemmap’s bounds will be respected during
pfn_to_page()/page_to_pfn() operations.
The conversion macros will produce correct SV39/48/57 addresses
for every possible/valid DRAM_BASE inside the physical memory limits.

v2:Address Alex's comments

The Linux kernel CVE team has assigned CVE-2024-26795 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 5.4 with commit d95f1a542c3d and fixed in 5.10.212 with commit 8af1c121b010
	Issue introduced in 5.4 with commit d95f1a542c3d and fixed in 5.15.151 with commit 5941a90c55d3
	Issue introduced in 5.4 with commit d95f1a542c3d and fixed in 6.1.81 with commit 8310080799b4
	Issue introduced in 5.4 with commit d95f1a542c3d and fixed in 6.6.21 with commit a278d5c60f21
	Issue introduced in 5.4 with commit d95f1a542c3d and fixed in 6.7.9 with commit 2a1728c15ec4
	Issue introduced in 5.4 with commit d95f1a542c3d and fixed in 6.8 with commit a11dd49dcb93

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-26795
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	arch/riscv/include/asm/pgtable.h

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/8af1c121b0102041809bc137ec600d1865eaeedd
	https://git.kernel.org/stable/c/5941a90c55d3bfba732b32208d58d997600b44ef
	https://git.kernel.org/stable/c/8310080799b40fd9f2a8b808c657269678c149af
	https://git.kernel.org/stable/c/a278d5c60f21aa15d540abb2f2da6e6d795c3e6e
	https://git.kernel.org/stable/c/2a1728c15ec4f45ed9248ae22f626541c179bfbe
	https://git.kernel.org/stable/c/a11dd49dcb9376776193e15641f84fcc1e5980c9