Description
In the Linux kernel, the following vulnerability has been resolved: net_sched: sch_sfq: reject invalid perturb period Gerrard Tai reported that SFQ perturb_period has no range check yet, and this can be used to trigger a race condition fixed in a separate patch. We want to make sure ctl->perturb_period * HZ will not overflow and is positive. tc qd add dev lo root sfq perturb -10 # negative value : error Error: sch_sfq: invalid perturb period. tc qd add dev lo root sfq perturb 1000000000 # too big : error Error: sch_sfq: invalid perturb period. tc qd add dev lo root sfq perturb 2000000 # acceptable value tc -s -d qd sh dev lo qdisc sfq 8005: root refcnt 2 limit 127p quantum 64Kb depth 127 flows 128 divisor 1024 perturb 2000000sec Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) backlog 0b 0p requeues 0
Affected products
linux: linux kernel; debian: debian linux
References10
- git.kernel.org/stable/c/0357da9149eac621f39e235a135ebf155f01f7c3 Patch
- git.kernel.org/stable/c/2254d038dab9c194fe6a4b1ce31034f42e91a6e5 Patch
- git.kernel.org/stable/c/590b2d7d0beadba2aa576708a05a05f0aae39295 Patch
- git.kernel.org/stable/c/7ca52541c05c832d32b112274f81a985101f9ba8 Patch
- git.kernel.org/stable/c/956b5aebb349449b38d920d444ca1392d43719d1 Patch
- git.kernel.org/stable/c/b11a50544af691b787384089b68f740ae20a441b Patch
- git.kernel.org/stable/c/e0936ff56be4e08ad5b60ec26971eae0c40af305 Patch
- git.kernel.org/stable/c/f9b97d466e6026ccbdda30bb5b71965b67ccbc82 Patch
- lists.debian.org/debian-lts-announce/2025/10/msg00007.html Third Party Advisory
- lists.debian.org/debian-lts-announce/2025/10/msg00008.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: 11 · as of 7 November 2026
- CWE
- CWE-190
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