CVE-2022-50636
In the Linux kernel, the following vulnerability has been resolved: PCI: Fix pci_device_is_present() for VFs by checking PF pci_device_is_present() previously didn't work for VFs because it reads the Vendor and Device ID, which are 0xffff for VFs, which…
Does this matter?
Not yet scored. NVD analysis is pending; check back once CVSS and EPSS values are published.
Description
In the Linux kernel, the following vulnerability has been resolved: PCI: Fix pci_device_is_present() for VFs by checking PF pci_device_is_present() previously didn't work for VFs because it reads the Vendor and Device ID, which are 0xffff for VFs, which looks like they aren't present. Check the PF instead. Wei Gong reported that if virtio I/O is in progress when the driver is unbound or "0" is written to /sys/.../sriov_numvfs, the virtio I/O operation hangs, which may result in output like this: task:bash state:D stack: 0 pid: 1773 ppid: 1241 flags:0x00004002 Call Trace: schedule+0x4f/0xc0 blk_mq_freeze_queue_wait+0x69/0xa0 blk_mq_freeze_queue+0x1b/0x20 blk_cleanup_queue+0x3d/0xd0 virtblk_remove+0x3c/0xb0 [virtio_blk] virtio_dev_remove+0x4b/0x80 ... device_unregister+0x1b/0x60 unregister_virtio_device+0x18/0x30 virtio_pci_remove+0x41/0x80 pci_device_remove+0x3e/0xb0 This happened because pci_device_is_present(VF) returned "false" in virtio_pci_remove(), so it called virtio_break_device(). The broken vq meant that vring_interrupt() skipped the vq.callback() that would have completed the virtio I/O operation via virtblk_done(). [bhelgaas: commit log, simplify to always use pci_physfn(), add stable tag]
- CVSS
- Not yet scored
- EPSS
- 0.21% probability · 11th percentile
- CISA KEV
- Not listed
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/518573988a2f14f517403db2ece5ddaefba21e94
- https://git.kernel.org/stable/c/643d77fda08d06f863af35e80a7e517ea61d9629
- https://git.kernel.org/stable/c/65bd0962992abd42e77a05e68c7b40e7c73726d1
- https://git.kernel.org/stable/c/67fd41bbb0f51aa648a47f728b99e6f1fa2ccc34
- https://git.kernel.org/stable/c/81565e51ccaf6fff8910e997ee22e16b5e1dabc3
- https://git.kernel.org/stable/c/98b04dd0b4577894520493d96bc4623387767445
- https://git.kernel.org/stable/c/99ef6cc791584495987dd11b14769b450dfa5820
- https://git.kernel.org/stable/c/f4b44c7766dae2b8681f621941cabe9f14066d59
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.