CVE-2026-89685 (GCVE-0-2026-89685)
Vulnerability from cvelistv5
Published
2026-09-11 19:46
Modified
2026-10-21 12:48
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
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
Impacted products
Vendor Product Version
Linux Linux Version: 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf
Version: 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf
Version: 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf
Version: 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf
Version: 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf
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