{
  "id": "CVE-2024-39276",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2024-06-25T15:15:13.903",
  "lastModified": "2024-11-21T09:27:23.107",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix mb_cache_entry's e_refcnt leak in ext4_xattr_block_cache_find()\n\nSyzbot reports a warning as follows:\n\n============================================\nWARNING: CPU: 0 PID: 5075 at fs/mbcache.c:419 mb_cache_destroy+0x224/0x290\nModules linked in:\nCPU: 0 PID: 5075 Comm: syz-executor199 Not tainted 6.9.0-rc6-gb947cc5bf6d7\nRIP: 0010:mb_cache_destroy+0x224/0x290 fs/mbcache.c:419\nCall Trace:\n <TASK>\n ext4_put_super+0x6d4/0xcd0 fs/ext4/super.c:1375\n generic_shutdown_super+0x136/0x2d0 fs/super.c:641\n kill_block_super+0x44/0x90 fs/super.c:1675\n ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7327\n[...]\n============================================\n\nThis is because when finding an entry in ext4_xattr_block_cache_find(), if\next4_sb_bread() returns -ENOMEM, the ce's e_refcnt, which has already grown\nin the __entry_find(), won't be put away, and eventually trigger the above\nissue in mb_cache_destroy() due to reference count leakage.\n\nSo call mb_cache_entry_put() on the -ENOMEM error branch as a quick fix."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: soluciona la fuga de e_refcnt de mb_cache_entry en ext4_xattr_block_cache_find() Syzbot informa una advertencia de la siguiente manera: ======================= ======================= ADVERTENCIA: CPU: 0 PID: 5075 en fs/mbcache.c:419 mb_cache_destroy+0x224/0x290 M\u00f3dulos vinculados en: CPU: 0 PID: 5075 Comm: syz-executor199 No contaminado 6.9.0-rc6-gb947cc5bf6d7 RIP: 0010:mb_cache_destroy+0x224/0x290 fs/mbcache.c:419 Seguimiento de llamadas:  ext4_put_super+0x6d4/0xcd0 fs/ext4/super .c:1375 generic_shutdown_super+0x136/0x2d0 fs/super.c:641 kill_block_super+0x44/0x90 fs/super.c:1675 ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7327 [...] === ========================================= Esto se debe a que al encontrar una entrada en ext4_xattr_block_cache_find (), si ext4_sb_bread() devuelve -ENOMEM, el e_refcnt del ce, que ya ha crecido en __entry_find(), no se guardar\u00e1 y, eventualmente, desencadenar\u00e1 el problema anterior en mb_cache_destroy() debido a una fuga del recuento de referencias. Entonces llame a mb_cache_entry_put() en la rama de error -ENOMEM como soluci\u00f3n r\u00e1pida."
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6
      }
    ]
  },
  "references": [
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