Subject: CVE-2024-35885: mlxbf_gige: stop interface during shutdown

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

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

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

mlxbf_gige: stop interface during shutdown

The mlxbf_gige driver intermittantly encounters a NULL pointer
exception while the system is shutting down via "reboot" command.
The mlxbf_driver will experience an exception right after executing
its shutdown() method.  One example of this exception is:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000070
Mem abort info:
  ESR = 0x0000000096000004
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x04: level 0 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000004
  CM = 0, WnR = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=000000011d373000
[0000000000000070] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 96000004 [#1] SMP
CPU: 0 PID: 13 Comm: ksoftirqd/0 Tainted: G S         OE     5.15.0-bf.6.gef6992a #1
Hardware name: https://www.mellanox.com BlueField SoC/BlueField SoC, BIOS 4.0.2.12669 Apr 21 2023
pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : mlxbf_gige_handle_tx_complete+0xc8/0x170 [mlxbf_gige]
lr : mlxbf_gige_poll+0x54/0x160 [mlxbf_gige]
sp : ffff8000080d3c10
x29: ffff8000080d3c10 x28: ffffcce72cbb7000 x27: ffff8000080d3d58
x26: ffff0000814e7340 x25: ffff331cd1a05000 x24: ffffcce72c4ea008
x23: ffff0000814e4b40 x22: ffff0000814e4d10 x21: ffff0000814e4128
x20: 0000000000000000 x19: ffff0000814e4a80 x18: ffffffffffffffff
x17: 000000000000001c x16: ffffcce72b4553f4 x15: ffff80008805b8a7
x14: 0000000000000000 x13: 0000000000000030 x12: 0101010101010101
x11: 7f7f7f7f7f7f7f7f x10: c2ac898b17576267 x9 : ffffcce720fa5404
x8 : ffff000080812138 x7 : 0000000000002e9a x6 : 0000000000000080
x5 : ffff00008de3b000 x4 : 0000000000000000 x3 : 0000000000000001
x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 mlxbf_gige_handle_tx_complete+0xc8/0x170 [mlxbf_gige]
 mlxbf_gige_poll+0x54/0x160 [mlxbf_gige]
 __napi_poll+0x40/0x1c8
 net_rx_action+0x314/0x3a0
 __do_softirq+0x128/0x334
 run_ksoftirqd+0x54/0x6c
 smpboot_thread_fn+0x14c/0x190
 kthread+0x10c/0x110
 ret_from_fork+0x10/0x20
Code: 8b070000 f9000ea0 f95056c0 f86178a1 (b9407002)
---[ end trace 7cc3941aa0d8e6a4 ]---
Kernel panic - not syncing: Oops: Fatal exception in interrupt
Kernel Offset: 0x4ce722520000 from 0xffff800008000000
PHYS_OFFSET: 0x80000000
CPU features: 0x000005c1,a3330e5a
Memory Limit: none
---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---

During system shutdown, the mlxbf_gige driver's shutdown() is always executed.
However, the driver's stop() method will only execute if networking interface
configuration logic within the Linux distribution has been setup to do so.

If shutdown() executes but stop() does not execute, NAPI remains enabled
and this can lead to an exception if NAPI is scheduled while the hardware
interface has only been partially deinitialized.

The networking interface managed by the mlxbf_gige driver must be properly
stopped during system shutdown so that IFF_UP is cleared, the hardware
interface is put into a clean state, and NAPI is fully deinitialized.

The Linux kernel CVE team has assigned CVE-2024-35885 to this issue.

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

	Issue introduced in 5.14 with commit f92e1869d74e and fixed in 5.15.154 with commit 63a10b530e22
	Issue introduced in 5.14 with commit f92e1869d74e and fixed in 6.1.85 with commit 80247e0eca14
	Issue introduced in 5.14 with commit f92e1869d74e and fixed in 6.6.26 with commit 36a1cb0371aa
	Issue introduced in 5.14 with commit f92e1869d74e and fixed in 6.8.5 with commit 9783b3b0e71d
	Issue introduced in 5.14 with commit f92e1869d74e and fixed in 6.9 with commit 09ba28e1cd3c

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-2024-35885
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/mlxbf_gige/mlxbf_gige_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/63a10b530e22cc923008b5925821c26872f37971
	https://git.kernel.org/stable/c/80247e0eca14ff177d565f58ecd3010f6b7910a4
	https://git.kernel.org/stable/c/36a1cb0371aa6f0698910ee70cb4ed3c349f4fa4
	https://git.kernel.org/stable/c/9783b3b0e71d704949214a8f76468f591a31f3f5
	https://git.kernel.org/stable/c/09ba28e1cd3cf715daab1fca6e1623e22fd754a6