Subject: CVE-2024-35959: net/mlx5e: Fix mlx5e_priv_init() cleanup flow

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

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

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

net/mlx5e: Fix mlx5e_priv_init() cleanup flow

When mlx5e_priv_init() fails, the cleanup flow calls mlx5e_selq_cleanup which
calls mlx5e_selq_apply() that assures that the `priv->state_lock` is held using
lockdep_is_held().

Acquire the state_lock in mlx5e_selq_cleanup().

Kernel log:
=============================
WARNING: suspicious RCU usage
6.8.0-rc3_net_next_841a9b5 #1 Not tainted
-----------------------------
drivers/net/ethernet/mellanox/mlx5/core/en/selq.c:124 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
2 locks held by systemd-modules/293:
 #0: ffffffffa05067b0 (devices_rwsem){++++}-{3:3}, at: ib_register_client+0x109/0x1b0 [ib_core]
 #1: ffff8881096c65c0 (&device->client_data_rwsem){++++}-{3:3}, at: add_client_context+0x104/0x1c0 [ib_core]

stack backtrace:
CPU: 4 PID: 293 Comm: systemd-modules Not tainted 6.8.0-rc3_net_next_841a9b5 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x8a/0xa0
 lockdep_rcu_suspicious+0x154/0x1a0
 mlx5e_selq_apply+0x94/0xa0 [mlx5_core]
 mlx5e_selq_cleanup+0x3a/0x60 [mlx5_core]
 mlx5e_priv_init+0x2be/0x2f0 [mlx5_core]
 mlx5_rdma_setup_rn+0x7c/0x1a0 [mlx5_core]
 rdma_init_netdev+0x4e/0x80 [ib_core]
 ? mlx5_rdma_netdev_free+0x70/0x70 [mlx5_core]
 ipoib_intf_init+0x64/0x550 [ib_ipoib]
 ipoib_intf_alloc+0x4e/0xc0 [ib_ipoib]
 ipoib_add_one+0xb0/0x360 [ib_ipoib]
 add_client_context+0x112/0x1c0 [ib_core]
 ib_register_client+0x166/0x1b0 [ib_core]
 ? 0xffffffffa0573000
 ipoib_init_module+0xeb/0x1a0 [ib_ipoib]
 do_one_initcall+0x61/0x250
 do_init_module+0x8a/0x270
 init_module_from_file+0x8b/0xd0
 idempotent_init_module+0x17d/0x230
 __x64_sys_finit_module+0x61/0xb0
 do_syscall_64+0x71/0x140
 entry_SYSCALL_64_after_hwframe+0x46/0x4e
 </TASK>

The Linux kernel CVE team has assigned CVE-2024-35959 to this issue.

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

	Issue introduced in 5.18 with commit 8bf30be75069 and fixed in 6.1.87 with commit ad26f26abd35
	Issue introduced in 5.18 with commit 8bf30be75069 and fixed in 6.6.28 with commit f9ac93b6f3de
	Issue introduced in 5.18 with commit 8bf30be75069 and fixed in 6.8.7 with commit 6bd77865fda6
	Issue introduced in 5.18 with commit 8bf30be75069 and fixed in 6.9 with commit ecb829459a84

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-2024-35959
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/en/selq.c
	drivers/net/ethernet/mellanox/mlx5/core/en_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/ad26f26abd353113dea4e8d5ebadccdab9b61e76
	https://git.kernel.org/stable/c/f9ac93b6f3de34aa0bb983b9be4f69ca50fc70f3
	https://git.kernel.org/stable/c/6bd77865fda662913dcb5722a66a773840370aa7
	https://git.kernel.org/stable/c/ecb829459a841198e142f72fadab56424ae96519