CVE-2026-90248net/sched: cls_api: fix teardown of an adopted proto on insert-race loss
- —Not scoredno CVSS score yet
- 0.21%Exploitation in 30 daysEPSS · top 89% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_api: fix teardown of an adopted proto on insert-race loss In tc_new_tfilter() the create branch sets tp_created = 1 before calling tcf_chain_tp_insert_unique(). When the caller loses the race (another request inserted a proto at the same chain/prio first), insert_unique() destroys the caller's own tp_new and returns the winner's proto with an extra reference. tp_created was never cleared, so the loser's errout path treated the winner's live proto as its own and called tcf_chain_tp_delete_empty() on it, silently unlinking an active classifier that the winning request already advertised via RTM_NEWTFILTER. Track the outcome of the insert step in a single tri-state variable so each errout path reacts correctly: - TP_NOT_CREATED: no proto created; pursue the old path. - TP_CREATED: proto inserted successfully; same code path as before. - TP_NOT_OWNED: New - lost the insert race; tp is another request's proto (chain ref already released by tp_new's destroy) Both errout reactions are single expressions derived from the state. This fix is motivated by the Sashiko's automated review of Patch (net/sched: cls_api: Always acquire rtnl_lock when destroying locked classifiers) [1][2]. The review identified the silent-unlink behaviour of an adopted proto's teardown when a request loses the tcf_chain_tp_insert_unique() race. [1] https://sashiko.dev/#/patchset/20260801125632.360365-1-jhs%40mojatatu.com [2] https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260801125632.360365-1-jhs%40mojatatu.com
Timeline
ID reserved
By Linux
- 6 days later
· 6 days later
Published
- 32 days later
· 32 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.21% · top 89% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected 8b64678e0af8f4d62a40149baedebe78503a5255 – < a68e664ddf16ecae6d769d6a2eb356f8abab75c9
- affected 8b64678e0af8f4d62a40149baedebe78503a5255 – < df02b6dc136af45e92ee4c86f4aa6c9a60790b1e
- affected 8b64678e0af8f4d62a40149baedebe78503a5255 – < bee2208276c8e0e40a249ffdcf6e5434a79a847c
- affected 8b64678e0af8f4d62a40149baedebe78503a5255 – < 219c87aeefdcc8c1caf28cc99e9b361ce7393d3a
- affected 8b64678e0af8f4d62a40149baedebe78503a5255 – < bbe2fd6d77df630356185406a97317f6aa6a92cf
- affected 8b64678e0af8f4d62a40149baedebe78503a5255 – < dc8b33b819cb02a75936940c120aa669ad89942d
- affected 8b64678e0af8f4d62a40149baedebe78503a5255 – < d4e359b3608a0e184bbe8d61a5c3b50d0831c44a
- affected 5.1
- unaffected < 5.1
- unaffected 5.15.221 – ≤ 5.15.*
- unaffected 6.1.188 – ≤ 6.1.*
- unaffected 6.6.157 – ≤ 6.6.*
- unaffected 6.12.110 – ≤ 6.12.*
- unaffected 6.18.52 – ≤ 6.18.*
- unaffected 7.2.6 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References7
- https://git.kernel.org/stable/c/a68e664ddf16ecae6d769d6a2eb356f8abab75c9 (opens in a new tab)
- https://git.kernel.org/stable/c/df02b6dc136af45e92ee4c86f4aa6c9a60790b1e (opens in a new tab)
- https://git.kernel.org/stable/c/bee2208276c8e0e40a249ffdcf6e5434a79a847c (opens in a new tab)
- https://git.kernel.org/stable/c/219c87aeefdcc8c1caf28cc99e9b361ce7393d3a (opens in a new tab)
- https://git.kernel.org/stable/c/bbe2fd6d77df630356185406a97317f6aa6a92cf (opens in a new tab)
- https://git.kernel.org/stable/c/dc8b33b819cb02a75936940c120aa669ad89942d (opens in a new tab)
- https://git.kernel.org/stable/c/d4e359b3608a0e184bbe8d61a5c3b50d0831c44a (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-81841 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://cveledger.app/cve/CVE-2026-90248)Record last updated .