CVE-2025-39819

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: fs/smb: Fix inconsistent refcnt update A possible inconsistent update of refcount was identified in `smb2_compound_op`. Such inconsistent update could lead to possible resource leaks. Why it is a possible bug: 1. In the comment section of the function, it clearly states that the reference to `cfile` should be dropped after calling this function. 2. Every control flow path would check and drop the reference to `cfile`, except the patched one. 3. Existing callers would not handle refcount update of `cfile` if -ENOMEM is returned. To fix the bug, an extra goto label "out" is added, to make sure that the cleanup logic would always be respected. As the problem is caused by the allocation failure of `vars`, the cleanup logic between label "finished" and "out" can be safely ignored. According to the definition of function `is_replayable_error`, the error code of "-ENOMEM" is not recoverable. Therefore, the replay logic also gets ignored.

Severity

MEDIUM

CVSS score

5.5 (v3.1)

Vulnerability status

Modified

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2025-09-16 13:15:58.260000

Last modified

2026-10-19 21:10:00.160000

View original CVE JSON

{
  "id": "CVE-2025-39819",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2025-09-16T13:15:58.260",
  "lastModified": "2026-10-19T21:10:00.160",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs/smb: Fix inconsistent refcnt update\n\nA possible inconsistent update of refcount was identified in `smb2_compound_op`.\nSuch inconsistent update could lead to possible resource leaks.\n\nWhy it is a possible bug:\n1. In the comment section of the function, it clearly states that the\nreference to `cfile` should be dropped after calling this function.\n2. Every control flow path would check and drop the reference to\n`cfile`, except the patched one.\n3. Existing callers would not handle refcount update of `cfile` if\n-ENOMEM is returned.\n\nTo fix the bug, an extra goto label \"out\" is added, to make sure that the\ncleanup logic would always be respected. As the problem is caused by the\nallocation failure of `vars`, the cleanup logic between label \"finished\"\nand \"out\" can be safely ignored. According to the definition of function\n`is_replayable_error`, the error code of \"-ENOMEM\" is not recoverable.\nTherefore, the replay logic also gets ignored."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nfs/smb: Corrección de actualización inconsistente de refcnt\n\nSe identificó una posible actualización inconsistente de refcount en 'smb2_compound_op'.\nDicha actualización inconsistente podría llevar a posibles fugas de recursos.\n\nPor qué es un posible error:\n1. En la sección de comentarios de la función, se indica claramente que la referencia a 'cfile' debería liberarse después de llamar a esta función.\n2. Cada ruta de flujo de control verificaría y liberaría la referencia a 'cfile', excepto la parcheada.\n3. Los llamadores existentes no manejarían la actualización de refcount de 'cfile' si se devuelve -ENOMEM.\n\nPara corregir el error, se añade una etiqueta 'goto' adicional 'out', para asegurar que la lógica de limpieza siempre se respetaría. Como el problema es causado por el fallo de asignación de 'vars', la lógica de limpieza entre la etiqueta 'finished' y 'out' puede ignorarse de forma segura. Según la definición de la función 'is_replayable_error', el código de error '-ENOMEM' no es recuperable. Por lo tanto, la lógica de reintento también se ignora."
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          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
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  "weaknesses": [
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      "description": [
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