CVE-2021-47646 (GCVE-0-2021-47646)
Vulnerability from cvelistv5
Published
2025-02-26 01:54
Modified
2026-05-11 13:58
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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
References
Impacted products
Vendor Product Version
Linux Linux Version: aee69d78dec0ffdf82e35d57c626e80dddc314d5
Version: aee69d78dec0ffdf82e35d57c626e80dddc314d5
Version: aee69d78dec0ffdf82e35d57c626e80dddc314d5
Version: aee69d78dec0ffdf82e35d57c626e80dddc314d5
Version: aee69d78dec0ffdf82e35d57c626e80dddc314d5
Version: aee69d78dec0ffdf82e35d57c626e80dddc314d5
Version: aee69d78dec0ffdf82e35d57c626e80dddc314d5
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