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CVE-2021-47646 Detail

Description

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


Metrics

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CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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Hyperlink 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 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-416 Use After Free CISA-ADP  

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Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-47646
NVD Published Date:
02/26/2025
NVD Last Modified:
03/24/2025
Source:
kernel.org