CVE-2021-47646 (GCVE-0-2021-47646)

Vulnerability from cvelistv5 – Published: 2025-02-26 01:54 – Updated: 2025-05-04 07:15
VLAI?
Title
Revert "Revert "block, bfq: honor already-setup queue merges""
Summary
In the Linux kernel, the following vulnerability has been resolved: Revert "Revert "block, bfq: honor already-setup queue merges"" A crash [1] happened to be triggered in conjunction with commit 2d52c58b9c9b ("block, bfq: honor already-setup queue merges"). The latter was then reverted by commit ebc69e897e17 ("Revert "block, bfq: honor already-setup queue merges""). Yet, the reverted commit was not the one introducing the bug. In fact, it actually triggered a UAF introduced by a different commit, and now fixed by commit d29bd41428cf ("block, bfq: reset last_bfqq_created on group change"). So, there is no point in keeping commit 2d52c58b9c9b ("block, bfq: honor already-setup queue merges") out. This commit restores it. [1] https://bugzilla.kernel.org/show_bug.cgi?id=214503
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: aee69d78dec0ffdf82e35d57c626e80dddc314d5 , < f990f0985eda59d4f29fc83fcf300c92b1225d39 (git)
Affected: aee69d78dec0ffdf82e35d57c626e80dddc314d5 , < 931aff627469a75c77b9fd3823146d0575afffd6 (git)
Affected: aee69d78dec0ffdf82e35d57c626e80dddc314d5 , < cc051f497eac9d8a0d816cd4bffa3415f2724871 (git)
Affected: aee69d78dec0ffdf82e35d57c626e80dddc314d5 , < 65d8a737452e88f251fe5d925371de6d606df613 (git)
Affected: aee69d78dec0ffdf82e35d57c626e80dddc314d5 , < abc2129e646af7b43025d90a071f83043f1ae76c (git)
Affected: aee69d78dec0ffdf82e35d57c626e80dddc314d5 , < 4083925bd6dc89216d156474a8076feec904e607 (git)
Affected: aee69d78dec0ffdf82e35d57c626e80dddc314d5 , < 15729ff8143f8135b03988a100a19e66d7cb7ecd (git)
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    Linux Linux Affected: 4.12
Unaffected: 0 , < 4.12 (semver)
Unaffected: 4.19.238 , ≤ 4.19.* (semver)
Unaffected: 5.4.189 , ≤ 5.4.* (semver)
Unaffected: 5.10.110 , ≤ 5.10.* (semver)
Unaffected: 5.15.33 , ≤ 5.15.* (semver)
Unaffected: 5.16.19 , ≤ 5.16.* (semver)
Unaffected: 5.17.2 , ≤ 5.17.* (semver)
Unaffected: 5.18 , ≤ * (original_commit_for_fix)
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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.