CVE-2026-89663

CVE CVE-2026-89663EUVD EUVD-2026-76575Veröffentlicht 2026-09-11T19:45:50.000ZZuletzt geändert 2026-09-14T12:01:53.000ZCVSS 8.8

Was das Advisory beschreibt

In the Linux kernel, the following vulnerability has been resolved: nfsd: revoke copy-notify stateids before dropping their reference Copy-notify stateids live in the s2s_cp_stateids IDR and on their parent stid's sc_cp_list, pinned by a single membership reference. _free_cpntf_state_locked() only unlinks an entry once its refcount reaches zero, so any revoke path that runs while a concurrent find_cpntf_state()/manage_cpntf_state() holder has elevated cs_count drops the reference without unlinking, leaving the entry discoverable with its membership reference already consumed. A second revoke or a laundromat tick then frees it while the reader still holds the pointer -- a KASAN-detectable use-after-free at the reader's nfs4_put_cpntf_state(). This affected all three revoke paths: - The parent-stid drain (nfs4_free_cpntf_statelist()) repeatedly called _free_cpntf_state_locked() on the first list entry; a holder that had bumped cs_count made it return early, so the next iteration re-decremented and burned the holder's reference. - OFFLOAD_CANCEL (manage_cpntf_state()) and laundromat expiry likewise used _free_cpntf_state_locked() and could drop 2->1 without unlinking. Add revoke_cpntf_state_locked(), which unhashes the entry from the IDR and sc_cp_list first (deferring the final free to any holder), and use it from all three revoke paths. The drain now walks with list_for_each_entry_safe() and revokes each entry unconditionally, so it terminates in one pass per entry regardless of cs_count. The unhash is gated on !list_empty(&cps->cp_list); the idr_remove() gate matters because idr_alloc_cyclic() may have recycled the so_id by then. Keep _free_cpntf_state_locked() for the reference-holder put path only, where a concurrent revoke may already have unlinked the entry (its list_del_init() then a no-op).

Quelle: EUVD (ENISA), im Wortlaut der Meldung.

Produkte, die das Advisory nennt

Diese Angaben stammen aus der Meldung selbst, nicht aus einer Prüfung durch uns.

• Linux — Linux 624322f1adc58acd0b69f77a6ddc764207e97241 <6b8149448cdcb476fba4559d1ecc247efee9971b; patch: 5.10.270; patch: 5.15.221; 624322f1adc58acd0b69f77a6ddc764207e97241 <5f00e0ab4de45d4f9e4bd0883cf2517acf63fc0d; 624322f1adc58acd0b69f77a6ddc764207e97241 <06a62f6dbc60791f4229c6950b1eec6b18df9af1; patch: 6.6.157; 624322f1adc58acd0b69f77a6ddc764207e97241 <3b0c3595db99bb4bebd7c8aa8a36f3c50e411bb7; 624322f1adc58acd0b69f77a6ddc764207e97241 <b56d2c5f01cddbeca7d11cce81d97db4ec9a464f; patch: 7.3-rc1; 624322f1adc58acd0b69f77a6ddc764207e97241 <caddbeffab1eaba1d2bcf5ceda35547863466705; patch: 7.2.4; 624322f1adc58acd0b69f77a6ddc764207e97241 <ff8a3cff02b92b2a82f1a9876038fcf953ae9c25; patch: 6.1.188; patch: 0; 5.6; patch: 6.18.50; patch: 6.12.109; 624322f1adc58acd0b69f77a6ddc764207e97241 <a1fca0f7bbb7b100a39c7ba8dd7922c87c4237a3

Die genannten Versionen sind die Angabe der Meldung. Patchlage vergleicht keine Versionsnummern und leitet aus ihnen keine Aussage ab — welche Version installiert ist, muss ein Mensch nachsehen.

Im Produktkatalog geführt

Für diese Produkte kann ein Bestand in Patchlage erfasst werden. Ein Advisory dazu erscheint am Morgen danach im Lagebericht.

• Linux — Linux

Patchlage meldet Treffer und Verdachtsfälle. Zu allem anderen sagt dieses System nichts — weder diese Seite noch der Lagebericht behauptet je, dass ein Bestand sicher ist.