CVE-2025-37890 (GCVE-0-2025-37890)

Vulnerability from cvelistv5 – Published: 2025-05-16 13:01 – Updated: 2025-11-03 19:57
VLAI?
Title
net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc
Summary
In the Linux kernel, the following vulnerability has been resolved: net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc As described in Gerrard's report [1], we have a UAF case when an hfsc class has a netem child qdisc. The crux of the issue is that hfsc is assuming that checking for cl->qdisc->q.qlen == 0 guarantees that it hasn't inserted the class in the vttree or eltree (which is not true for the netem duplicate case). This patch checks the n_active class variable to make sure that the code won't insert the class in the vttree or eltree twice, catering for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea , < 273bbcfa53541cde38b2003ad88a59b770306421 (git)
Affected: 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea , < e0cf8ee23e1915431f262a7b2dee0c7a7d699af0 (git)
Affected: 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea , < e3e949a39a91d1f829a4890e7dfe9417ac72e4d0 (git)
Affected: 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea , < 8df7d37d626430035b413b97cee18396b3450bef (git)
Affected: 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea , < 6082a87af4c52f58150d40dec1716011d871ac21 (git)
Affected: 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea , < 2e7093c7a8aba5d4f8809f271488e5babe75e202 (git)
Affected: 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea , < ac39fd4a757584d78ed062d4f6fd913f83bd98b5 (git)
Affected: 37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea , < 141d34391abbb315d68556b7c67ad97885407547 (git)
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    Linux Linux Affected: 5.0
Unaffected: 0 , < 5.0 (semver)
Unaffected: 5.4.294 , ≤ 5.4.* (semver)
Unaffected: 5.10.238 , ≤ 5.10.* (semver)
Unaffected: 5.15.182 , ≤ 5.15.* (semver)
Unaffected: 6.1.138 , ≤ 6.1.* (semver)
Unaffected: 6.6.90 , ≤ 6.6.* (semver)
Unaffected: 6.12.28 , ≤ 6.12.* (semver)
Unaffected: 6.14.6 , ≤ 6.14.* (semver)
Unaffected: 6.15 , ≤ * (original_commit_for_fix)
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