Description
In the Linux kernel, the following vulnerability has been resolved: sch_htb: make htb_qlen_notify() idempotent htb_qlen_notify() always deactivates the HTB class and in fact could trigger a warning if it is already deactivated. Therefore, it is not idempotent and not friendly to its callers, like fq_codel_dequeue(). Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers' life.
Affected products
linux: linux kernel; debian: debian linux
References10
- git.kernel.org/stable/c/0a188c0e197383683fd093ab1ea6ce9a5869a6ea Patch
- git.kernel.org/stable/c/32ae12ce6a9f6bace186ca7335220ff59b6cc3cd Patch
- git.kernel.org/stable/c/5ba8b837b522d7051ef81bacf3d95383ff8edce5 Patch
- git.kernel.org/stable/c/73cf6af13153d62f9b76eff422eea79dbc70f15e Patch
- git.kernel.org/stable/c/967955c9e57f8eebfccc298037d4aaf3d42bc1c9 Patch
- git.kernel.org/stable/c/a61f1b5921761fbaf166231418bc1db301e5bf59 Patch
- git.kernel.org/stable/c/bbbf5e0f87078b715e7a665d662a2c0e77f044ae Patch
- git.kernel.org/stable/c/e6b45f4de763b00dc1c55e685e2dd1aaf525d3c1 Patch
- lists.debian.org/debian-lts-announce/2025/08/msg00010.html Third Party Advisory
- lists.debian.org/debian-lts-announce/2025/10/msg00007.html Third Party Advisory
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 15 · as of 7 November 2026
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