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GHSA-J642-RP5Q-W8W9

Vulnerability from github – Published: 2024-03-15 21:30 – Updated: 2025-01-14 15:30

Details

In the Linux kernel, the following vulnerability has been resolved:

io_uring: fix ltout double free on completion race

Always remove linked timeout on io_link_timeout_fn() from the master request link list, otherwise we may get use-after-free when first io_link_timeout_fn() puts linked timeout in the fail path, and then will be found and put on master's free.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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  "aliases": [
    "CVE-2021-47123"
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    "severity": "HIGH"
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  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: fix ltout double free on completion race\n\nAlways remove linked timeout on io_link_timeout_fn() from the master\nrequest link list, otherwise we may get use-after-free when first\nio_link_timeout_fn() puts linked timeout in the fail path, and then\nwill be found and put on master\u0027s free.",
  "id": "GHSA-j642-rp5q-w8w9",
  "modified": "2025-01-14T15:30:48Z",
  "published": "2024-03-15T21:30:44Z",
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CVE-2021-47123 (GCVE-0-2021-47123)

Vulnerability from cvelistv5 – Published: 2024-03-15 20:14 – Updated: 2026-08-05 08:46

Title

io_uring: fix ltout double free on completion race

Summary

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix ltout double free on completion race Always remove linked timeout on io_link_timeout_fn() from the master request link list, otherwise we may get use-after-free when first io_link_timeout_fn() puts linked timeout in the fail path, and then will be found and put on master's free.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-09-10 15:55 UTC

Assigner

Linux mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/1f64f5e903b9d1d15…
https://git.kernel.org/stable/c/447c19f3b5074409c…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 90cd7e424969d29aff653333b4dcb4e2e199d791 , < 1f64f5e903b9d1d157875721e02adadc9d6f0a5d (git) Affected: 90cd7e424969d29aff653333b4dcb4e2e199d791 , < 447c19f3b5074409c794b350b10306e1da1ef4ba (git)
Linux	Linux	Affected: 5.11 Unaffected: 0 , < 5.11 (semver) Unaffected: 5.12.10 , ≤ 5.12.* (semver) Unaffected: 5.13 , ≤ * (original_commit_for_fix)

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JSON

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Sightings

Author	Source	Type	Date	Other

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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GHSA-J642-RP5Q-W8W9

CVE-2021-47123 (GCVE-0-2021-47123)

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