CVSS
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Описание
Оригинално описание
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_hfsc: Don't make class passive twice update_vf() is called from two places for the same class during a single dequeue when the class's child qdisc (e.g. codel/fq_codel) drops its last packets while dequeuing: 1. The child calls qdisc_tree_reduce_backlog(), which, now that the child is empty, invokes hfsc_qlen_notify() -> update_vf(cl, 0, 0) and turns the class passive (cl_nactive is decremented up the hierarchy). 2. hfsc_dequeue() then calls update_vf(cl, qdisc_pkt_len(skb), cur_time) to charge the dequeued bytes. On the second call the class is already passive, but its child qdisc is still empty, so update_vf() arms go_passive again: if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC) go_passive = 1; The leaf is then skipped by the cl_nactive == 0 check inside the loop, which does not clear go_passive, so the stale go_passive propagates to the parent and decrements its cl_nactive a second time. A parent that still has other active children is driven to cl_nactive == 0 and removed from the vttree, even though those siblings are still backlogged. They are never dequeued again and the qdisc stalls. Fix this by only arming go_passive when the class is actually active, so an already-passive class no longer triggers a second passive transition. The byte accounting (cl->cl_total += len) still runs for every ancestor, so dequeued bytes continue to be counted exactly once.
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- Linux Linux: 72c61ffbeeb8c50f6d4d70c65d3283aa1bac57a7 преди a425c82ff06cda5165e0de3de8c2a445ec1f863e; a5efc95a33bd4fcb879250852828cc58c7862970 преди fc973ecd1a079b9a87c360478542f3a56dea085b; 0475c85426b18eccdcb7f9fb58d8f8e9c6c58c87 преди 15720cd8fa3fc625146128f89a8e11b0449a20a7; 9030a91235ae4845ec71902c3e0cecfc9ed1f2df преди b2a017bfcf565721918ec7355a373911d2f2a227; d06476714d2819b550e0cc39222347e2c8941c9d преди 9221a594c72a1446137926d4c2aa04e345f798dc; 51eb3b65544c9efd6a1026889ee5fb5aa62da3bb преди 66dbb13eeb2fc339f8f548a9076be4c1a94857b0; 51eb3b65544c9efd6a1026889ee5fb5aa62da3bb преди 3a49bbae676fef1ffe548971e6229ae2adeb9d10; 51eb3b65544c9efd6a1026889ee5fb5aa62da3bb преди 90b662ea25f5e83bb3b8ccec5b93ced810b92fb8; 9a5fd5c2f4d4afdd5e405083ee53e0789ce76956; c1175c4ad01dbc9c979d099861fa90a754f72059; 5.10.241 преди 5.10.261; 5.15.190 преди 5.15.212; 6.1.138 преди 6.1.178; 6.6.90 преди 6.6.145; 6.12.28 преди 6.12.97; 5.4.297 преди 5.5; 6.14.6 преди 6.15
- Linux Linux: 6.15; преди 6.15; 5.10.261 до 5.10.*; 5.15.212 до 5.15.*; 6.1.178 до 6.1.*; 6.6.145 до 6.6.*; 6.12.97 до 6.12.*; 6.18.40 до 6.18.*; 7.1.5 до 7.1.*; от 7.2 нататък
История
- 15 август 2026 Публикувано
Други уязвимости в Linux Linux
Първоизточници
- https://www.cve.org/CVERecord?id=CVE-2026-74284
- https://nvd.nist.gov/vuln/detail/CVE-2026-74284
- https://git.kernel.org/stable/c/a425c82ff06cda5165e0de3de8c2a445ec1f863e
- https://git.kernel.org/stable/c/fc973ecd1a079b9a87c360478542f3a56dea085b
- https://git.kernel.org/stable/c/15720cd8fa3fc625146128f89a8e11b0449a20a7
- https://git.kernel.org/stable/c/b2a017bfcf565721918ec7355a373911d2f2a227
- https://git.kernel.org/stable/c/9221a594c72a1446137926d4c2aa04e345f798dc
- https://git.kernel.org/stable/c/66dbb13eeb2fc339f8f548a9076be4c1a94857b0
- https://git.kernel.org/stable/c/3a49bbae676fef1ffe548971e6229ae2adeb9d10
- https://git.kernel.org/stable/c/90b662ea25f5e83bb3b8ccec5b93ced810b92fb8