CVE-2022-49434
MediumIn 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]]
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-667CVE-2022-49434 is a Improper Locking vulnerability
What is Improper Locking?
The product does not properly acquire or release a lock, which can lead to unexpected behaviour. Learn more on MITRE CWE
Affected versions
Linux kernel versions
4.13
and later are affected. Fixed in
4.14.283,
4.19.247,
5.4.198,
5.10.121,
5.15.46,
5.17.14,
5.18.3,
5.19
and their respective stable series.
References
The following references provide additional information about CVE-2022-49434 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/2cdd5284035322795b0964f899eefba254cfe483
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PatchKernel patch commithttps://git.kernel.org/stable/c/59ea6b3ae51df7cd6bfd84c9c0030609b9315622
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PatchKernel patch commithttps://git.kernel.org/stable/c/a91ee0e9fca9d7501286cfbced9b30a33e52740a
Frequently asked questions
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What is CVE-2022-49434?
CVE-2022-49434 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as an Improper Locking flaw (CWE-667) . It affects Linux kernel versions from 4.13 onward and has been patched in 4.14.283, 4.19.247, 5.4.198 and others. CVE-2022-49434 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2022-49434?
CVE-2022-49434 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2022-49434?
Yes — CVE-2022-49434 has been patched. Fixed versions include 4.14.283, 4.19.247, 5.4.198 and others. If you are running Linux kernel 4.13 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2022-49434 actively exploited?
No — CVE-2022-49434 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Improper Locking (CWE-667)?
The product does not properly acquire or release a lock, which can lead to unexpected behaviour. View CWE-667 on MITRE CWE →