CVE-2025-38177
sch_hfsc: make hfsc_qlen_notify() idempotent
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
CISA's decision points: whether it is exploited, whether attacks can be automated, and how much control an attacker gets. Assessed (SSVC 2.0.3).What do these mean? →
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
In the Linux kernel, the following vulnerability has been resolved: sch_hfsc: make hfsc_qlen_notify() idempotent hfsc_qlen_notify() is not idempotent either and not friendly to its callers, like fq_codel_dequeue(). Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers' life: 1. update_vf() decreases cl->cl_nactive, so we can check whether it is non-zero before calling it. 2. eltree_remove() always removes RB node cl->el_node, but we can use RB_EMPTY_NODE() + RB_CLEAR_NODE() to make it safe.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
4.14
References 8
git.kernel.org
- stable/c/9a5fd5c2f4d4afdd5e405083ee53e0789ce76956
- stable/c/72c61ffbeeb8c50f6d4d70c65d3283aa1bac57a7
- stable/c/a5efc95a33bd4fcb879250852828cc58c7862970
- stable/c/0475c85426b18eccdcb7f9fb58d8f8e9c6c58c87
- stable/c/9030a91235ae4845ec71902c3e0cecfc9ed1f2df
- stable/c/d06476714d2819b550e0cc39222347e2c8941c9d
- stable/c/c1175c4ad01dbc9c979d099861fa90a754f72059
- stable/c/51eb3b65544c9efd6a1026889ee5fb5aa62da3bb