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.
Advisories
Source ID Title
Debian DLA Debian DLA DLA-4102-1 linux-6.1 security update
Debian DLA Debian DLA DLA-4178-1 linux security update
EUVD EUVD EUVD-2025-5127 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.
Ubuntu USN Ubuntu USN USN-7510-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-4 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-5 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-6 Linux kernel (AWS FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-7 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-8 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7511-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7511-2 Linux kernel (GCP FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7511-3 Linux kernel (GKE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7512-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7521-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7521-2 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7521-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7593-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7602-1 Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7703-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7703-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7703-3 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-7703-4 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7719-1 Linux kernel (Raspberry Pi Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7737-1 Linux kernel (Azure) vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 28 Oct 2025 20:45:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel

Wed, 30 Apr 2025 15:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-99

Thu, 13 Mar 2025 12:30:00 +0000


Fri, 28 Feb 2025 02:00:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Thu, 27 Feb 2025 02:45:00 +0000

Type Values Removed Values Added
Description 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.
Title NFSD: fix hang in nfsd4_shutdown_callback
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T07:21:23.769Z

Reserved: 2024-12-29T08:45:45.767Z

Link: CVE-2025-21795

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2025-02-27T03:15:20.390

Modified: 2025-10-28T20:39:50.750

Link: CVE-2025-21795

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-02-27T00:00:00Z

Links: CVE-2025-21795 - Bugzilla

cve-icon OpenCVE Enrichment

No data.