net/sched: ets: clamp quantum in parse and fallback paths
In the Linux kernel, the following vulnerability has been resolved: net/sched: ets: clamp quantum in parse and fallback paths ets_qdisc_change() falls back to psched_mtu() with no floor for bands without an explicit quantum. With a crafted size table qdisc_pkt_len reaches ~2 GiB, so a zero psched_mtu on a headerless device makes the deficit-refill loop spin under the qdisc lock. Move the floor into ets_quantum_parse() so explicitly configured quanta are also clamped to [256, 1<<20], not just the fallback path. Conditions to recreate the bug: CONFIG_NET_SCH_ETS=y. Requires CAP_NET_ADMIN (namespace-local via unshare -Urn suffices). tc qdisc add dev dummy0 root ets bands 3 strict 2 quanta 1 1
- Products
- Kernel
- Affected versions
- Not specified
- Fixed versions
- 5.10.271, 5.15.222, 6.1.189, 6.12.111, 6.18.53, 6.6.158, 7.2.7
- CVEs
- CVE-2026-98009
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 11:31 UTC · Revision 1
Source evidence
net/sched: ets: clamp quantum in parse and fallback paths
core-osv · Original sourcePublished 25 Sept 2026, 10:23 UTC
In the Linux kernel, the following vulnerability has been resolved: net/sched: ets: clamp quantum in parse and fallback paths ets_qdisc_change() falls back to psched_mtu() with no floor for bands without an explicit quantum. With a crafted size table qdisc_pkt_len reaches ~2 GiB, so a zero psched_mtu on a headerless device makes the deficit-refill loop spin under the qdisc lock. Move the floor into ets_quantum_parse() so explicitly configured quanta are also clamped to [256, 1<<20], not just the fallback path. Conditions to recreate the bug: CONFIG_NET_SCH_ETS=y. Requires CAP_NET_ADMIN (namespace-local via unshare -Urn suffices). tc qdisc add dev dummy0 root ets bands 3 strict 2 quanta 1 1
osv:CVE-2026-98009
Kernel
Fixed versions: 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2.7
Complete source record
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