CVE-2021-47646

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2021-47646
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

7.8 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://git.kernel.org/stable/c/15729ff8143f8135b03988a100a19e66d7cb7ecd Patch
https://git.kernel.org/stable/c/4083925bd6dc89216d156474a8076feec904e607 Patch
https://git.kernel.org/stable/c/65d8a737452e88f251fe5d925371de6d606df613 Patch
https://git.kernel.org/stable/c/931aff627469a75c77b9fd3823146d0575afffd6 Patch
https://git.kernel.org/stable/c/abc2129e646af7b43025d90a071f83043f1ae76c Patch
https://git.kernel.org/stable/c/cc051f497eac9d8a0d816cd4bffa3415f2724871 Patch
https://git.kernel.org/stable/c/f990f0985eda59d4f29fc83fcf300c92b1225d39 Patch
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
History

24 Mar 2025, 17:46

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/15729ff8143f8135b03988a100a19e66d7cb7ecd - () https://git.kernel.org/stable/c/15729ff8143f8135b03988a100a19e66d7cb7ecd - Patch
References () https://git.kernel.org/stable/c/4083925bd6dc89216d156474a8076feec904e607 - () https://git.kernel.org/stable/c/4083925bd6dc89216d156474a8076feec904e607 - Patch
References () https://git.kernel.org/stable/c/65d8a737452e88f251fe5d925371de6d606df613 - () https://git.kernel.org/stable/c/65d8a737452e88f251fe5d925371de6d606df613 - Patch
References () https://git.kernel.org/stable/c/931aff627469a75c77b9fd3823146d0575afffd6 - () https://git.kernel.org/stable/c/931aff627469a75c77b9fd3823146d0575afffd6 - Patch
References () https://git.kernel.org/stable/c/abc2129e646af7b43025d90a071f83043f1ae76c - () https://git.kernel.org/stable/c/abc2129e646af7b43025d90a071f83043f1ae76c - Patch
References () https://git.kernel.org/stable/c/cc051f497eac9d8a0d816cd4bffa3415f2724871 - () https://git.kernel.org/stable/c/cc051f497eac9d8a0d816cd4bffa3415f2724871 - Patch
References () https://git.kernel.org/stable/c/f990f0985eda59d4f29fc83fcf300c92b1225d39 - () https://git.kernel.org/stable/c/f990f0985eda59d4f29fc83fcf300c92b1225d39 - Patch
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
First Time Linux linux Kernel
Linux

27 Feb 2025, 18:15

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: Revert "Revert "block, bfq: respetar las fusiones de colas ya configuradas"" Se produjo un fallo [1] junto con la confirmación 2d52c58b9c9b ("block, bfq: respetar las fusiones de colas ya configuradas"). Esta última se revirtió mediante la confirmación ebc69e897e17 ("Revert "block, bfq: respetar las fusiones de colas ya configuradas""). Sin embargo, la confirmación revertida no fue la que introdujo el error. De hecho, activó una UAF introducida por una confirmación diferente, y ahora corregida por la confirmación d29bd41428cf ("block, bfq: restablecer last_bfqq_created al cambiar de grupo"). Por lo tanto, no tiene sentido mantener la confirmación 2d52c58b9c9b ("block, bfq: respetar las fusiones de colas ya configuradas"). Esta confirmación la restaura. [1] https://bugzilla.kernel.org/show_bug.cgi?id=214503
CWE CWE-416
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 7.8

26 Feb 2025, 06:37

Type Values Removed Values Added
New CVE
Information

Published : 2025-02-26 06:37

Updated : 2025-03-24 17:46

NVD link : CVE-2021-47646

Mitre link : CVE-2021-47646

CVE.ORG link : CVE-2021-47646

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-416

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