• CVE-2022-48817

发布时间: 2024年8月20日

修改时间: 2024年8月20日

概要

In the Linux kernel, the following vulnerability has been resolved: net: dsa: ar9331: register the mdiobus under devres 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 ar9331 is an MDIO device, so the initial set of constraints that I thought would cause this (I2C or SPI buses which call -&gt;remove on -&gt;shutdown) do not apply. But there is one more which applies here. If the DSA master itself is on a bus that calls -&gt;remove from -&gt;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 ar9331 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 ar9331 driver doesn't have a complex code structure for mdiobus removal, so just replace of_mdiobus_register with the devres variant in order to be all-devres and ensure that we don't free a still-registered bus.

CVSS v3 指标

NVD openEuler
Confidentiality None
Attack Vector Local
CVSS评分 N/A 5.5
Attack Complexity Low
Privileges Required Low
Scope Unchanged
Integrity None
User Interaction None
Availability High

安全公告

公告名 概要 发布时间
KylinSec-SA-2024-3326 In the Linux kernel, the following vulnerability has been resolved: net: dsa: ar9331: register the mdiobus under devres 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 ar9331 is an MDIO device, so the initial set of constraints that I thought would cause this (I2C or SPI buses which call -&gt;remove on -&gt;shutdown) do not apply. But there is one more which applies here. If the DSA master itself is on a bus that calls -&gt;remove from -&gt;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 ar9331 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 ar9331 driver doesn't have a complex code structure for mdiobus removal, so just replace of_mdiobus_register with the devres variant in order to be all-devres and ensure that we don't free a still-registered bus. 2024年8月20日

影响产品

产品 状态
KY3.4-5A kernel Unaffected
KY3.5.2 kernel Unaffected
KY3.5.3 kernel Unaffected
V6 kernel Unaffected