CVE-2026-89685

Source
https://cve.org/CVERecord?id=CVE-2026-89685
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89685.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-89685
Downstream
Published
2026-09-11T19:46:07Z
Modified
2026-09-13T03:47:20Z
Summary
nfsd: fix clock domain mismatch in clients_still_reclaiming()
Details

In the Linux kernel, the following vulnerability has been resolved:

nfsd: fix clock domain mismatch in clients_still_reclaiming()

clients_still_reclaiming() computes a deadline from nn->boot_time (CLOCK_REALTIME, ~1.7 billion) but compares it against ktime_get_boottime_seconds() (CLOCK_BOOTTIME, seconds since boot). The comparison is always false — it would take ~54 years of uptime for BOOTTIME to exceed the REALTIME-derived deadline.

This means any client can hold the server in grace indefinitely by sending CLAIM_PREVIOUS OPEN requests, blocking all non-reclaim operations for all other clients.

Add boot_time_bt (CLOCK_BOOTTIME) alongside the existing boot_time and use it for the deadline computation. boot_time (CLOCK_REALTIME) is preserved for its cl_boot clientid-nonce role.

Database specific
{
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89685.json"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
20b7d86f29d39e8ae19bb29c24ffee70dc385ddf
Fixed
f9cec313efb2fd18d962aad738a4892bce806016
Fixed
9843649196221152b6e5d138a3ce859bdaae1d96
Fixed
09ea3eb9a518565f5bca386e81b993ed8825f5e8

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89685.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
5.6.0
Fixed
6.18.51
Type
ECOSYSTEM
Events
Introduced
6.19.0
Fixed
7.2.4

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89685.json"