{"id":"DEBIAN-CVE-2021-47646","details":"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","modified":"2026-09-15T09:02:36.093396273Z","published":"2025-02-26T06:37:06.390Z","upstream":["CVE-2021-47646"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2021-47646"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.17.3-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47646.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.17.3-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47646.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.17.3-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47646.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}