nfsd: revoke copy-notify stateids before dropping their reference
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
CVE-2026-89663
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-89663
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "624322f1adc58acd0b69f77a6ddc764207e97241",
"lessThan": "5f00e0ab4de45d4f9e4bd0883cf2517acf63fc0d",
"versionType": "git"
},
{
"status": "affected",
"version": "624322f1adc58acd0b69f77a6ddc764207e97241",
"lessThan": "06a62f6dbc60791f4229c6950b1eec6b18df9af1",
"versionType": "git"
},
{
"status": "affected",
"version": "624322f1adc58acd0b69f77a6ddc764207e97241",
"lessThan": "a1fca0f7bbb7b100a39c7ba8dd7922c87c4237a3",
"versionType": "git"
},
{
"status": "affected",
"version": "624322f1adc58acd0b69f77a6ddc764207e97241",
"lessThan": "caddbeffab1eaba1d2bcf5ceda35547863466705",
"versionType": "git"
},
{
"status": "affected",
"version": "624322f1adc58acd0b69f77a6ddc764207e97241",
"lessThan": "6b8149448cdcb476fba4559d1ecc247efee9971b",
"versionType": "git"
},
{
"status": "affected",
"version": "624322f1adc58acd0b69f77a6ddc764207e97241",
"lessThan": "b56d2c5f01cddbeca7d11cce81d97db4ec9a464f",
"versionType": "git"
},
{
"status": "affected",
"version": "624322f1adc58acd0b69f77a6ddc764207e97241",
"lessThan": "ff8a3cff02b92b2a82f1a9876038fcf953ae9c25",
"versionType": "git"
},
{
"status": "affected",
"version": "624322f1adc58acd0b69f77a6ddc764207e97241",
"lessThan": "3b0c3595db99bb4bebd7c8aa8a36f3c50e411bb7",
"versionType": "git"
}
],
"programFiles": [
"fs/nfsd/nfs4state.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.6"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.6",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.270",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.221",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.109",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/nfsd/nfs4state.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89663
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #35154 · Revision 1
- Added to Heist Feed
- Publisher date