Subject: CVE-2024-26988: init/main.c: Fix potential static_command_line memory overflow

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

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

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

init/main.c: Fix potential static_command_line memory overflow

We allocate memory of size 'xlen + strlen(boot_command_line) + 1' for
static_command_line, but the strings copied into static_command_line are
extra_command_line and command_line, rather than extra_command_line and
boot_command_line.

When strlen(command_line) > strlen(boot_command_line), static_command_line
will overflow.

This patch just recovers strlen(command_line) which was miss-consolidated
with strlen(boot_command_line) in the commit f5c7310ac73e ("init/main: add
checks for the return value of memblock_alloc*()")

The Linux kernel CVE team has assigned CVE-2024-26988 to this issue.

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

	Issue introduced in 5.1 with commit f5c7310ac73e and fixed in 5.10.216 with commit 2ef607ea1036
	Issue introduced in 5.1 with commit f5c7310ac73e and fixed in 5.15.157 with commit 0dc727a4e054
	Issue introduced in 5.1 with commit f5c7310ac73e and fixed in 6.1.88 with commit 76c2f4d426a5
	Issue introduced in 5.1 with commit f5c7310ac73e and fixed in 6.6.29 with commit 81cf85ae4f2d
	Issue introduced in 5.1 with commit f5c7310ac73e and fixed in 6.8.8 with commit 936a02b5a963
	Issue introduced in 5.1 with commit f5c7310ac73e and fixed in 6.9 with commit 46dad3c1e578

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-2024-26988
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:
	init/main.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/2ef607ea103616aec0289f1b65d103d499fa903a
	https://git.kernel.org/stable/c/0dc727a4e05400205358a22c3d01ccad2c8e1fe4
	https://git.kernel.org/stable/c/76c2f4d426a5358fced5d5990744d46f10a4ccea
	https://git.kernel.org/stable/c/81cf85ae4f2dd5fa3e43021782aa72c4c85558e8
	https://git.kernel.org/stable/c/936a02b5a9630c5beb0353c3085cc49d86c57034
	https://git.kernel.org/stable/c/46dad3c1e57897ab9228332f03e1c14798d2d3b9