CVE-2022-49434

Description

In the Linux kernel, the following vulnerability has been resolved: PCI: Avoid pci_dev_lock() AB/BA deadlock with sriov_numvfs_store() The sysfs sriov_numvfs_store() path acquires the device lock before the config space access lock: sriov_numvfs_store device_lock # A (1) acquire device lock sriov_configure vfio_pci_sriov_configure # (for example) vfio_pci_core_sriov_configure pci_disable_sriov sriov_disable pci_cfg_access_lock pci_wait_cfg # B (4) wait for dev->block_cfg_access == 0 Previously, pci_dev_lock() acquired the config space access lock before the device lock: pci_dev_lock pci_cfg_access_lock dev->block_cfg_access = 1 # B (2) set dev->block_cfg_access = 1 device_lock # A (3) wait for device lock Any path that uses pci_dev_lock(), e.g., pci_reset_function(), may deadlock with sriov_numvfs_store() if the operations occur in the sequence (1) (2) (3) (4). Avoid the deadlock by reversing the order in pci_dev_lock() so it acquires the device lock before the config space access lock, the same as the sriov_numvfs_store() path. [bhelgaas: combined and adapted commit log from Jay Zhou's independent subsequent posting: https://lore.kernel.org/r/20220404062539.1710-1-jianjay.zhou@huawei.com]

Gravité et risque d'exploitation

CVE-2022-49434 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 0.21 %, ce qui la place devant 11.3 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <ea047f51172aa68841adef7f52d375002438b8f0, <=5.17.*, <c9a81f9ed6ae3554621d6a50220b1bc74b67d81e, 5.15.46, <59ea6b3ae51df7cd6bfd84c9c0030609b9315622, 0, 5.19, <aed6d4d519210c28817948f34c53b6e058e0456c, <2cdd5284035322795b0964f899eefba254cfe483, 5.18.3, <=5.10.*, <=4.14.*, 17530e71e0166a37f8e20a9b7bcf1d50ae3cff8e, 5.10.121, 4.13, 5.17.14, 4.19.247, 5.4.198, <=5.18.*, <=5.4.*, <eff3587b9c01439b738298475e555c028ac9f55e, 4.14.283, <=4.19.*, <4.13, <a91ee0e9fca9d7501286cfbced9b30a33e52740a, <=*, <=5.15.*, <c3c6dc1853b8bf3c718f96fd8480a6eb09ba4831) 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.

Références

• https://git.kernel.org/stable/c/c3c6dc1853b8bf3c718f96fd8480a6eb09ba4831
• https://git.kernel.org/stable/c/aed6d4d519210c28817948f34c53b6e058e0456c
• https://git.kernel.org/stable/c/c9a81f9ed6ae3554621d6a50220b1bc74b67d81e
• https://git.kernel.org/stable/c/eff3587b9c01439b738298475e555c028ac9f55e
• https://git.kernel.org/stable/c/2cdd5284035322795b0964f899eefba254cfe483
• https://git.kernel.org/stable/c/ea047f51172aa68841adef7f52d375002438b8f0
• https://git.kernel.org/stable/c/59ea6b3ae51df7cd6bfd84c9c0030609b9315622
• https://git.kernel.org/stable/c/a91ee0e9fca9d7501286cfbced9b30a33e52740a