CVE-2025-38193
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
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
Vendor
Product
CWE
Yayın Tarihi
2025-07-04 14:15:26
Güncelleme
2025-12-18 21:25:10
Source Identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
KEV Date Added
-
Kategoriler
Referanslar
https://git.kernel.org/stable/c/0357da9149eac621f39e235a135ebf155f01f7c3
https://git.kernel.org/stable/c/2254d038dab9c194fe6a4b1ce31034f42e91a6e5
https://git.kernel.org/stable/c/590b2d7d0beadba2aa576708a05a05f0aae39295
https://git.kernel.org/stable/c/7ca52541c05c832d32b112274f81a985101f9ba8
https://git.kernel.org/stable/c/956b5aebb349449b38d920d444ca1392d43719d1
https://git.kernel.org/stable/c/b11a50544af691b787384089b68f740ae20a441b
https://git.kernel.org/stable/c/e0936ff56be4e08ad5b60ec26971eae0c40af305
https://git.kernel.org/stable/c/f9b97d466e6026ccbdda30bb5b71965b67ccbc82
https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html