CVE-2022-48813

2024-07-1612:15:05

Linux

web.nvd.nist.gov

linux kernel

vulnerability

net

dsa

felix

mdiobus

pci device

constraints

driver

mdiobus allocation

registration

devres

device link

unbind consumers

dpaa2-eth

fsl-mc bus

AI Score

6.7

Confidence

High

EPSS

Percentile

16.0%

JSON

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

net: dsa: felix: don’t use devres for mdiobus

As explained in commits:
74b6d7d13307 (“net: dsa: realtek: register the MDIO bus under devres”)
5135e96a3dd2 (“net: dsa: don’t allocate the slave_mii_bus using devres”)

mdiobus_free() will panic when called from devm_mdiobus_free() <-
devres_release_all() <- __device_release_driver(), and that mdiobus was
not previously unregistered.

The Felix VSC9959 switch is a PCI device, so the initial set of
constraints that I thought would cause this (I2C or SPI buses which call
->remove on ->shutdown) do not apply. But there is one more which
applies here.

If the DSA master itself is on a bus that calls ->remove from ->shutdown
(like dpaa2-eth, which is on the fsl-mc bus), there is a device link
between the switch and the DSA master, and device_links_unbind_consumers()
will unbind the felix switch driver on shutdown.

So the same treatment must be applied to all DSA switch drivers, which
is: either use devres for both the mdiobus allocation and registration,
or don’t use devres at all.

The felix driver has the code structure in place for orderly mdiobus
removal, so just replace devm_mdiobus_alloc_size() with the non-devres
variant, and add manual free where necessary, to ensure that we don’t
let devres free a still-registered bus.

Affected configurations

Vulners

Node

linuxlinux_kernelRange5.9–5.10.101

linuxlinux_kernelRange5.11.0–5.15.24

linuxlinux_kernelRange5.16.0–5.16.10

linuxlinux_kernelRange5.17.0≥

VendorProductVersionCPE
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

Vendor	Product	Version	CPE
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/net/dsa/ocelot/felix_vsc9959.c"
    ],
    "versions": [
      {
        "version": "ac3a68d56651",
        "lessThan": "95e5402f9430",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "ac3a68d56651",
        "lessThan": "8cda7577a0b4",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "ac3a68d56651",
        "lessThan": "9db6f056efd0",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "ac3a68d56651",
        "lessThan": "209bdb7ec6a2",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/net/dsa/ocelot/felix_vsc9959.c"
    ],
    "versions": [
      {
        "version": "5.9",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.9",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.101",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.24",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.16.10",
        "lessThanOrEqual": "5.16.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.17",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]