Subject: CVE-2024-46681: pktgen: use cpus_read_lock() in pg_net_init()

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

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

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

pktgen: use cpus_read_lock() in pg_net_init()

I have seen the WARN_ON(smp_processor_id() != cpu) firing
in pktgen_thread_worker() during tests.

We must use cpus_read_lock()/cpus_read_unlock()
around the for_each_online_cpu(cpu) loop.

While we are at it use WARN_ON_ONCE() to avoid a possible syslog flood.

The Linux kernel CVE team has assigned CVE-2024-46681 to this issue.

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

	Issue introduced in 2.6.12 with commit 1da177e4c3f4 and fixed in 6.10.8 with commit 5f5f7366dda8
	Issue introduced in 2.6.12 with commit 1da177e4c3f4 and fixed in 6.11 with commit 979b581e4c69

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-2024-46681
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:
	net/core/pktgen.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/5f5f7366dda8ae870e8305d6e7b3c0c2686cd2cf
	https://git.kernel.org/stable/c/979b581e4c69257acab1af415ddad6b2d78a2fa5