Subject: CVE-2024-26705: parisc: BTLB: Fix crash when setting up BTLB at CPU bringup

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

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

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

parisc: BTLB: Fix crash when setting up BTLB at CPU bringup

When using hotplug and bringing up a 32-bit CPU, ask the firmware about the
BTLB information to set up the static (block) TLB entries.

For that write access to the static btlb_info struct is needed, but
since it is marked __ro_after_init the kernel segfaults with missing
write permissions.

Fix the crash by dropping the __ro_after_init annotation.

The Linux kernel CVE team has assigned CVE-2024-26705 to this issue.

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

	Issue introduced in 6.6 with commit e5ef93d02d6c and fixed in 6.6.18 with commit 54944f45470a
	Issue introduced in 6.6 with commit e5ef93d02d6c and fixed in 6.7.6 with commit aa52be552766
	Issue introduced in 6.6 with commit e5ef93d02d6c and fixed in 6.8 with commit 913b9d443a01

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-2024-26705
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/parisc/kernel/cache.c

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/54944f45470af5965fb9c28cf962ec30f38a8f5b
	https://git.kernel.org/stable/c/aa52be55276614d33f22fbe7da36c40d6432d10b
	https://git.kernel.org/stable/c/913b9d443a0180cf0de3548f1ab3149378998486