Vulnerability-Lookup

FKIE_CVE-2026-22980

Vulnerability from fkie_nvd - Published: 2026-01-23 16:15 - Updated: 2026-02-26 18:48

Severity ?

7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: nfsd: provide locking for v4_end_grace Writing to v4_end_grace can race with server shutdown and result in memory being accessed after it was freed - reclaim_str_hashtbl in particularly. We cannot hold nfsd_mutex across the nfsd4_end_grace() call as that is held while client_tracking_op->init() is called and that can wait for an upcall to nfsdcltrack which can write to v4_end_grace, resulting in a deadlock. nfsd4_end_grace() is also called by the landromat work queue and this doesn't require locking as server shutdown will stop the work and wait for it before freeing anything that nfsd4_end_grace() might access. However, we must be sure that writing to v4_end_grace doesn't restart the work item after shutdown has already waited for it. For this we add a new flag protected with nn->client_lock. It is set only while it is safe to make client tracking calls, and v4_end_grace only schedules work while the flag is set with the spinlock held. So this patch adds a nfsd_net field "client_tracking_active" which is set as described. Another field "grace_end_forced", is set when v4_end_grace is written. After this is set, and providing client_tracking_active is set, the laundromat is scheduled. This "grace_end_forced" field bypasses other checks for whether the grace period has finished. This resolves a race which can result in use-after-free.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/06600719d0f7a723811c45e4d51f5b742f345309	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/2857bd59feb63fcf40fe4baf55401baea6b4feb4	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/34eb22836e0cdba093baac66599d68c4cd245a9d	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/53f07d095e7e680c5e4569a55a019f2c0348cdc6	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ba4811c8b433bfa681729ca42cc62b6034f223b0	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ca97360860eb02e3ae4ba42c19b439a0fcecbf06	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e8bfa2401d4c51eca6e48e9b33c798828ca9df61	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	6.19
linux	linux_kernel	6.19
linux	linux_kernel	6.19
linux	linux_kernel	6.19

JSON

To clipboard

{
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    }
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  "id": "CVE-2026-22980",
  "lastModified": "2026-02-26T18:48:11.530",
  "metrics": {
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          "attackVector": "LOCAL",
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          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
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        "impactScore": 5.9,
        "source": "nvd@nist.gov",
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      "source": "nvd@nist.gov",
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CVE-2026-22980 (GCVE-0-2026-22980)

Vulnerability from cvelistv5 – Published: 2026-01-23 15:24 – Updated: 2026-02-09 08:36

Title

nfsd: provide locking for v4_end_grace

Summary

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/ca97360860eb02e3a…
	https://git.kernel.org/stable/c/e8bfa2401d4c51eca…
	https://git.kernel.org/stable/c/34eb22836e0cdba09…
	https://git.kernel.org/stable/c/06600719d0f7a7238…
	https://git.kernel.org/stable/c/ba4811c8b433bfa68…
	https://git.kernel.org/stable/c/53f07d095e7e680c5…
	https://git.kernel.org/stable/c/2857bd59feb63fcf4…

Impacted products

Vendor

Product

Version

Linux

Affected: 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 , < ca97360860eb02e3ae4ba42c19b439a0fcecbf06 (git)
Affected: 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 , < e8bfa2401d4c51eca6e48e9b33c798828ca9df61 (git)
Affected: 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 , < 34eb22836e0cdba093baac66599d68c4cd245a9d (git)
Affected: 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 , < 06600719d0f7a723811c45e4d51f5b742f345309 (git)
Affected: 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 , < ba4811c8b433bfa681729ca42cc62b6034f223b0 (git)
Affected: 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 , < 53f07d095e7e680c5e4569a55a019f2c0348cdc6 (git)
Affected: 7f5ef2e900d9462bf9cffaf6bb246ed87a20a6d6 , < 2857bd59feb63fcf40fe4baf55401baea6b4feb4 (git)

Linux

Affected: 3.18
Unaffected: 0 , < 3.18 (semver)
Unaffected: 5.10.248 , ≤ 5.10.* (semver)
Unaffected: 5.15.198 , ≤ 5.15.* (semver)
Unaffected: 6.1.161 , ≤ 6.1.* (semver)
Unaffected: 6.6.121 , ≤ 6.6.* (semver)
Unaffected: 6.12.66 , ≤ 6.12.* (semver)
Unaffected: 6.18.6 , ≤ 6.18.* (semver)
Unaffected: 6.19 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
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      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/netns.h",
            "fs/nfsd/nfs4state.c",
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            "fs/nfsd/state.h"
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          "url": "https://git.kernel.org/stable/c/2857bd59feb63fcf40fe4baf55401baea6b4feb4"
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      "title": "nfsd: provide locking for v4_end_grace",
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  "cveMetadata": {
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-22980",
    "datePublished": "2026-01-23T15:24:02.924Z",
    "dateReserved": "2026-01-13T15:37:45.936Z",
    "dateUpdated": "2026-02-09T08:36:30.307Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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.

Action not permitted

FKIE_CVE-2026-22980

CVE-2026-22980 (GCVE-0-2026-22980)

Tags

Sightings

Nomenclature