CVE-2021-47111 (GCVE-0-2021-47111)

Vulnerability from cvelistv5 – Published: 2024-03-15 20:14 – Updated: 2025-05-04 07:04
VLAI?
Title
xen-netback: take a reference to the RX task thread
Summary
In the Linux kernel, the following vulnerability has been resolved: xen-netback: take a reference to the RX task thread Do this in order to prevent the task from being freed if the thread returns (which can be triggered by the frontend) before the call to kthread_stop done as part of the backend tear down. Not taking the reference will lead to a use-after-free in that scenario. Such reference was taken before but dropped as part of the rework done in 2ac061ce97f4. Reintroduce the reference taking and add a comment this time explaining why it's needed. This is XSA-374 / CVE-2021-28691.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 2ac061ce97f413bfbbdd768f7d2e0fda2e8170df , < 6b53db8c4c14b4e7256f058d202908b54a7b85b4 (git)
Affected: 2ac061ce97f413bfbbdd768f7d2e0fda2e8170df , < caec9bcaeb1a5f03f2d406305355c853af10c13e (git)
Affected: 2ac061ce97f413bfbbdd768f7d2e0fda2e8170df , < 107866a8eb0b664675a260f1ba0655010fac1e08 (git)
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    Linux Linux Affected: 5.5
Unaffected: 0 , < 5.5 (semver)
Unaffected: 5.10.43 , ≤ 5.10.* (semver)
Unaffected: 5.12.10 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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