CVE-2025-21795 (GCVE-0-2025-21795)

Vulnerability from cvelistv5 – Published: 2025-02-27 02:18 – Updated: 2026-05-12 12:03
VLAI?
Title
NFSD: fix hang in nfsd4_shutdown_callback
Summary
In the Linux kernel, the following vulnerability has been resolved: NFSD: fix hang in nfsd4_shutdown_callback If nfs4_client is in courtesy state then there is no point to send the callback. This causes nfsd4_shutdown_callback to hang since cl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP notifies NFSD that the connection was dropped. This patch modifies nfsd4_run_cb_work to skip the RPC call if nfs4_client is in courtesy state.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 67ef9e5fd737eab2495f2586df7e9ea30caa1b77 , < abed68027ea3ab893ac85cc46a00e2e64a324239 (git)
Affected: 26540b8940a2e21582afa61a6fb8af87310bac72 , < efa8a261c575f816c7e79a87aeb3ef8a0bd6b221 (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < 38d345f612503b850c2973e5a879f88e441b34d7 (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < 23ad7797c74cd8f7f90617f1e59a8703e2b43908 (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < cedfbb92cf97a6bff3d25633001d9c44442ee854 (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < e88d2451cd42e025465d6b51fd716a47b0b3800d (git)
Affected: 66af25799940b26efd41ea6e648f75c41a48a2c2 , < 036ac2778f7b28885814c6fbc07e156ad1624d03 (git)
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Linux Linux Affected: 5.19
Unaffected: 0 , < 5.19 (semver)
Unaffected: 5.10.235 , ≤ 5.10.* (semver)
Unaffected: 5.15.179 , ≤ 5.15.* (semver)
Unaffected: 6.1.129 , ≤ 6.1.* (semver)
Unaffected: 6.6.79 , ≤ 6.6.* (semver)
Unaffected: 6.12.16 , ≤ 6.12.* (semver)
Unaffected: 6.13.4 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.