Subject: CVE-2024-35988: riscv: Fix TASK_SIZE on 64-bit NOMMU

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

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

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

riscv: Fix TASK_SIZE on 64-bit NOMMU

On NOMMU, userspace memory can come from anywhere in physical RAM. The
current definition of TASK_SIZE is wrong if any RAM exists above 4G,
causing spurious failures in the userspace access routines.

The Linux kernel CVE team has assigned CVE-2024-35988 to this issue.

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

	Issue introduced in 5.5 with commit 6bd33e1ece52 and fixed in 5.10.216 with commit 04bf2e5f95c1
	Issue introduced in 5.5 with commit 6bd33e1ece52 and fixed in 5.15.158 with commit 52e8a42b1107
	Issue introduced in 5.5 with commit 6bd33e1ece52 and fixed in 6.1.90 with commit 4201b8c8f2c3
	Issue introduced in 5.5 with commit 6bd33e1ece52 and fixed in 6.6.30 with commit a0f0dbbb1bc4
	Issue introduced in 5.5 with commit 6bd33e1ece52 and fixed in 6.8.9 with commit efdcfa554b6e
	Issue introduced in 5.5 with commit 6bd33e1ece52 and fixed in 6.9 with commit 6065e736f82c

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-2024-35988
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/04bf2e5f95c1a52e28a7567a507f926efe31c3b6
	https://git.kernel.org/stable/c/52e8a42b11078d2aad4b9ba96503d77c7299168b
	https://git.kernel.org/stable/c/4201b8c8f2c32af321fb50867e68ac6c1cbed4be
	https://git.kernel.org/stable/c/a0f0dbbb1bc49fa0de18e92c36492ff6d804cdaa
	https://git.kernel.org/stable/c/efdcfa554b6eb228943ef1dd4d023c606be647d2
	https://git.kernel.org/stable/c/6065e736f82c817c9a597a31ee67f0ce4628e948