nfsd: fix clock domain mismatch in clients_still_reclaiming() (Linux Linux)

CVE-2026-89685
HIGH 7.5

At a glance

Source
NVD
EPSS
EPSS 0.61 % · percentile 49 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Received

Description

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.

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HLinux
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

European references

CERT-FR advisories

Affected products

ProductVersions
Linux · Linuxaffected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf < 7ca44a63d9a554ba7ad05b06d88746eab08b760e ; affected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf < 2c9efc6b692a153643d0f204b3c3632cb6b5761e ; affected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf < a22ee3a2cadef44f2edeb909ae36bd72450a3a35 ; affected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf < 04c3e4456fe76e8d7c94171009df3165c3262c51 ; affected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf < e92e80c5b043108029bc729b30d12c37158fb9cb ; affected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf < f9cec313efb2fd18d962aad738a4892bce806016
Linux · Linuxaffected 5.6 ; unaffected 0 < 5.6 ; unaffected 5.10.273 ≤ 5.10.* ; unaffected 5.15.224 ≤ 5.15.* ; unaffected 6.1.191 ≤ 6.1.* ; unaffected 6.6.160 ≤ 6.6.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD