CVE-2022-49434

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/[email protected]]

• linux linux kernel (< 4.9.318) • linux linux kernel (>= 4.10 < 4.14.283) • linux linux kernel (>= 4.15 < 4.19.247) • linux linux kernel (>= 4.20 < 5.4.198) • linux linux kernel (>= 5.5 < 5.10.121) • linux linux kernel (>= 5.11 < 5.15.46) • linux linux kernel (>= 5.16 < 5.17.14) • linux linux kernel (>= 5.18 < 5.18.3)