GHSA-m5hh-pp2g-6f3punknown
In the Linux kernel, the following vulnerability has been resolved: net/sched: drr: clamp...
🔗 CVE IDs covered (1)
📋 Description
In the Linux kernel, the following vulnerability has been resolved:
net/sched: drr: clamp quantum in change class
drr_change_class() rejects explicit quantum==0 but falls back to psched_mtu() with no floor. With a crafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1 (or a zero psched_mtu on a headerless device) makes the deficit-refill loop spin under the qdisc lock.
Add clamp_t(u32, quantum, 256, 1<<20) after the zero reject and on the fallback path. The explicit-zero reject is preserved.
Conditions to recreate the bug: CONFIG_NET_SCH_DRR=y. Requires CAP_NET_ADMIN (namespace-local via unshare -Urn suffices).
tc qdisc add dev dummy0 root drr tc class add dev dummy0 parent 1: classid 1:1 drr quantum 1
🔗 References (10)
- https://nvd.nist.gov/vuln/detail/CVE-2026-98010
- https://git.kernel.org/stable/c/8382abec0f1568d0a5590d75a3df92f23fcf5196
- https://git.kernel.org/stable/c/8f756ae1c87414ce9cc21b30e6e4c036d6e9e80b
- https://git.kernel.org/stable/c/d43cded350fe1218493ad3d37a276aff14108ae6
- https://git.kernel.org/stable/c/dc8b374214ef5bba4882bbd95b361e42555cfc0d
- https://git.kernel.org/stable/c/23fea7e6736b2e1c6f6f2f05cccf33d36834da73
- https://git.kernel.org/stable/c/560794ee6e040b6e1c4ac2b3c8909f341a4596ee
- https://git.kernel.org/stable/c/b464affe9f9dfe41ac48930c376e3fb8596651b0
- https://git.kernel.org/stable/c/e2297bbf9cf6ece86f1d1f8c683517a994990f9e
- https://github.com/advisories/GHSA-m5hh-pp2g-6f3p