CVE-2022-48812
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: net: dsa: lantiq_gswip: 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 GSWIP switch is a platform 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 GSWIP 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 gswip driver has the code structure in place for orderly mdiobus removal, so just replace devm_mdiobus_alloc() with the non-devres variant, and add manual free where necessary, to ensure that we don't let devres free a still-registered bus.
Gravité et risque d'exploitation
CVE-2022-48812 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.27 %, ce qui la place devant 18.1 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <=*, <0d120dfb5d67edc5bcd1804e167dba2b30809afd, <=5.15.*, ac3a68d56651c3dad2c12c7afce065fe15267f44, 5.16.10, 5.9, <=5.10.*, 5.10.101, 0, <5.9, <e177d2e85ebcd3008c4b2abc293f4118e04eedef, 5.17, <=5.16.*, 5.15.24, <2443ba2fe396bdde187a2fdfa6a57375643ae93c, <b5652bc50dde7b84e93dfb25479b64b817e377c1) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.