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CVE-2025-21810 (GCVE-0-2025-21810)

Vulnerability from cvelistv5 – Published: 2025-02-27 20:01 – Updated: 2026-08-05 11:54
VLAI
Title
driver core: class: Fix wild pointer dereferences in API class_dev_iter_next()
Summary
In the Linux kernel, the following vulnerability has been resolved: driver core: class: Fix wild pointer dereferences in API class_dev_iter_next() There are a potential wild pointer dereferences issue regarding APIs class_dev_iter_(init|next|exit)(), as explained by below typical usage: // All members of @iter are wild pointers. struct class_dev_iter iter; // class_dev_iter_init(@iter, @class, ...) checks parameter @class for // potential class_to_subsys() error, and it returns void type and does // not initialize its output parameter @iter, so caller can not detect // the error and continues to invoke class_dev_iter_next(@iter) even if // @iter still contains wild pointers. class_dev_iter_init(&iter, ...); // Dereference these wild pointers in @iter here once suffer the error. while (dev = class_dev_iter_next(&iter)) { ... }; // Also dereference these wild pointers here. class_dev_iter_exit(&iter); Actually, all callers of these APIs have such usage pattern in kernel tree. Fix by: - Initialize output parameter @iter by memset() in class_dev_iter_init() and give callers prompt by pr_crit() for the error. - Check if @iter is valid in class_dev_iter_next().
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 7b884b7f24b42fa25e92ed724ad82f137610afaf , < f4b9bc823b0cfdebfed479c0e87d6939c7562e87 (git)
Affected: 7b884b7f24b42fa25e92ed724ad82f137610afaf , < 1614e75d1a1b63db6421c7a4bf37004720c7376c (git)
Affected: 7b884b7f24b42fa25e92ed724ad82f137610afaf , < 5c504e9767b947cf7d4e29b811c0c8b3c53242b7 (git)
Affected: 7b884b7f24b42fa25e92ed724ad82f137610afaf , < e128f82f7006991c99a58114f70ef61e937b1ac1 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.4
Unaffected: 0 , < 6.4 (semver)
Unaffected: 6.6.76 , ≤ 6.6.* (semver)
Unaffected: 6.12.13 , ≤ 6.12.* (semver)
Unaffected: 6.13.2 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndriver core: class: Fix wild pointer dereferences in API class_dev_iter_next()\n\nThere are a potential wild pointer dereferences issue regarding APIs\nclass_dev_iter_(init|next|exit)(), as explained by below typical usage:\n\n// All members of @iter are wild pointers.\nstruct class_dev_iter iter;\n\n// class_dev_iter_init(@iter, @class, ...) checks parameter @class for\n// potential class_to_subsys() error, and it returns void type and does\n// not initialize its output parameter @iter, so caller can not detect\n// the error and continues to invoke class_dev_iter_next(@iter) even if\n// @iter still contains wild pointers.\nclass_dev_iter_init(\u0026iter, ...);\n\n// Dereference these wild pointers in @iter here once suffer the error.\nwhile (dev = class_dev_iter_next(\u0026iter)) { ... };\n\n// Also dereference these wild pointers here.\nclass_dev_iter_exit(\u0026iter);\n\nActually, all callers of these APIs have such usage pattern in kernel tree.\nFix by:\n- Initialize output parameter @iter by memset() in class_dev_iter_init()\n  and give callers prompt by pr_crit() for the error.\n- Check if @iter is valid in class_dev_iter_next()."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: n\u00facleo del controlador: clase: Arreglar desreferencias de punteros salvajes en la API class_dev_iter_next() Hay un posible problema de desreferencias de punteros salvajes con respecto a las API class_dev_iter_(init|next|exit()), como se explica a continuaci\u00f3n en el uso t\u00edpico: // Todos los miembros de @iter son punteros salvajes. struct class_dev_iter iter; // class_dev_iter_init(@iter, @class, ...) comprueba el par\u00e1metro @class en busca de un posible error class_to_subsys(), y devuelve el tipo void y no inicializa su par\u00e1metro de salida @iter, por lo que el llamador no puede detectar el error y contin\u00faa invocando class_dev_iter_next(@iter) incluso si @iter todav\u00eda contiene punteros salvajes. class_dev_iter_init(\u0026amp;iter, ...); // Desreferencia estos punteros salvajes en @iter aqu\u00ed una vez que sufre el error. mientras (dev = class_dev_iter_next(\u0026amp;iter)) { ... }; // Tambi\u00e9n desreferencia estos punteros salvajes aqu\u00ed. class_dev_iter_exit(\u0026amp;iter); En realidad, todos los que llaman a estas API tienen ese patr\u00f3n de uso en el \u00e1rbol del kernel. Solucione esto: - Inicialice el par\u00e1metro de salida @iter con memset() en class_dev_iter_init() y d\u00e9 a los que llaman un aviso con pr_crit() para el error. - Verifique si @iter es v\u00e1lido en class_dev_iter_next()."
          }
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                "lang": "en",
                "value": "CWE-476"
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    "redhat_vex": {
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      "current_release_date": "2026-07-30T10:13:28+00:00",
      "cve": "CVE-2025-21810",
      "id": "CVE-2025-21810",
      "initial_release_date": "2025-02-27T00:00:00+00:00",
      "product_status:known_affected": "226",
      "product_status:known_not_affected": "48",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: driver core: class: Fix wild pointer dereferences in API class_dev_iter_next()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-21810.json",
      "version": "3"
    }
  }
}



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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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