Subject: CVE-2024-35961: net/mlx5: Register devlink first under devlink lock

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

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

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

net/mlx5: Register devlink first under devlink lock

In case device is having a non fatal FW error during probe, the
driver will report the error to user via devlink. This will trigger
a WARN_ON, since mlx5 is calling devlink_register() last.
In order to avoid the WARN_ON[1], change mlx5 to invoke devl_register()
first under devlink lock.

[1]
WARNING: CPU: 5 PID: 227 at net/devlink/health.c:483 devlink_recover_notify.constprop.0+0xb8/0xc0
CPU: 5 PID: 227 Comm: kworker/u16:3 Not tainted 6.4.0-rc5_for_upstream_min_debug_2023_06_12_12_38 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: mlx5_health0000:08:00.0 mlx5_fw_reporter_err_work [mlx5_core]
RIP: 0010:devlink_recover_notify.constprop.0+0xb8/0xc0
Call Trace:
 <TASK>
 ? __warn+0x79/0x120
 ? devlink_recover_notify.constprop.0+0xb8/0xc0
 ? report_bug+0x17c/0x190
 ? handle_bug+0x3c/0x60
 ? exc_invalid_op+0x14/0x70
 ? asm_exc_invalid_op+0x16/0x20
 ? devlink_recover_notify.constprop.0+0xb8/0xc0
 devlink_health_report+0x4a/0x1c0
 mlx5_fw_reporter_err_work+0xa4/0xd0 [mlx5_core]
 process_one_work+0x1bb/0x3c0
 ? process_one_work+0x3c0/0x3c0
 worker_thread+0x4d/0x3c0
 ? process_one_work+0x3c0/0x3c0
 kthread+0xc6/0xf0
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork+0x1f/0x30
 </TASK>

The Linux kernel CVE team has assigned CVE-2024-35961 to this issue.

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

	Issue introduced in 5.16 with commit cf530217408e and fixed in 6.6.28 with commit 8c91c6085847
	Issue introduced in 5.16 with commit cf530217408e and fixed in 6.8.7 with commit 967caa3d37c0
	Issue introduced in 5.16 with commit cf530217408e and fixed in 6.9 with commit c6e77aa9dd82

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-2024-35961
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:
	drivers/net/ethernet/mellanox/mlx5/core/main.c
	drivers/net/ethernet/mellanox/mlx5/core/sf/dev/driver.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/8c91c60858473731bcdaf04fda99fcbcf84420d4
	https://git.kernel.org/stable/c/967caa3d37c078e5b95a32094657e6a4cad145f0
	https://git.kernel.org/stable/c/c6e77aa9dd82bc18a89bf49418f8f7e961cfccc8