Description (CNA)
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 ->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 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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected ac3a68d56651c3dad2c12c7afce065fe15267f44 before 475ce5dcf2d88fd4f3c213a0ac944e3e40702970; affected ac3a68d56651c3dad2c12c7afce065fe15267f44 before aae1c6a1d3d696fc33b609fb12fe744a556d1dc5; affected ac3a68d56651c3dad2c12c7afce065fe15267f44 before f1842a8cb71de4d7eb75a86f76e88c7ee739218c; affected ac3a68d56651c3dad2c12c7afce065fe15267f44 before 50facd86e9fbc4b93fe02e5fe05776047f45dbfb |
| Linux / Linux | affected 5.9; unaffected 0 before 5.9; unaffected 5.10.101 through 5.10.*; unaffected 5.15.24 through 5.15.*; unaffected 5.16.10 through 5.16.*; unaffected 5.17 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/475ce5dcf2d88fd4f3c213a0ac944e3e40702970
- https://git.kernel.org/stable/c/aae1c6a1d3d696fc33b609fb12fe744a556d1dc5
- https://git.kernel.org/stable/c/f1842a8cb71de4d7eb75a86f76e88c7ee739218c
- https://git.kernel.org/stable/c/50facd86e9fbc4b93fe02e5fe05776047f45dbfb
ADP enrichment
No English description supplied.
No English description supplied.
No references supplied.