{"id":"CVE-2022-49434","url":"https://www.cyber-defence.io/tools/cve/CVE-2022-49434","generatedAt":"2026-10-27T17:45:29.648Z","title":"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…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nPCI: Avoid pci_dev_lock() AB/BA deadlock with sriov_numvfs_store()\n\nThe sysfs sriov_numvfs_store() path acquires the device lock before the\nconfig space access lock:\n\n  sriov_numvfs_store\n    device_lock                 # A (1) acquire device lock\n    sriov_configure\n      vfio_pci_sriov_configure  # (for example)\n        vfio_pci_core_sriov_configure\n          pci_disable_sriov\n            sriov_disable\n              pci_cfg_access_lock\n                pci_wait_cfg    # B (4) wait for dev->block_cfg_access == 0\n\nPreviously, pci_dev_lock() acquired the config space access lock before the\ndevice lock:\n\n  pci_dev_lock\n    pci_cfg_access_lock\n      dev->block_cfg_access = 1 # B (2) set dev->block_cfg_access = 1\n    device_lock                 # A (3) wait for device lock\n\nAny path that uses pci_dev_lock(), e.g., pci_reset_function(), may\ndeadlock with sriov_numvfs_store() if the operations occur in the sequence\n(1) (2) (3) (4).\n\nAvoid the deadlock by reversing the order in pci_dev_lock() so it acquires\nthe device lock before the config space access lock, the same as the\nsriov_numvfs_store() path.\n\n[bhelgaas: combined and adapted commit log from Jay Zhou's independent\nsubsequent posting:\nhttps://lore.kernel.org/r/20220404062539.1710-1-jianjay.zhou@huawei.com]","published":"2025-02-26T07:01:20.000Z","lastModified":"2026-06-17T05:18:02.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-667"],"affected":["linux/linux kernel"],"epss":{"score":0.00215,"percentile":0.11857,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.21%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/2cdd5284035322795b0964f899eefba254cfe483","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/59ea6b3ae51df7cd6bfd84c9c0030609b9315622","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a91ee0e9fca9d7501286cfbced9b30a33e52740a","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/aed6d4d519210c28817948f34c53b6e058e0456c","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c3c6dc1853b8bf3c718f96fd8480a6eb09ba4831","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c9a81f9ed6ae3554621d6a50220b1bc74b67d81e","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ea047f51172aa68841adef7f52d375002438b8f0","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/eff3587b9c01439b738298475e555c028ac9f55e","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2022-49434","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}