nvd-json-data-feeds/CVE-2024/CVE-2024-267xx/CVE-2024-26720.json

{
  "id": "CVE-2024-26720",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2024-04-03T15:15:53.993",
  "lastModified": "2024-07-18T12:15:02.847",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again\n\n(struct dirty_throttle_control *)->thresh is an unsigned long, but is\npassed as the u32 divisor argument to div_u64().  On architectures where\nunsigned long is 64 bytes, the argument will be implicitly truncated.\n\nUse div64_u64() instead of div_u64() so that the value used in the \"is\nthis a safe division\" check is the same as the divisor.\n\nAlso, remove redundant cast of the numerator to u64, as that should happen\nimplicitly.\n\nThis would be difficult to exploit in memcg domain, given the ratio-based\narithmetic domain_drity_limits() uses, but is much easier in global\nwriteback domain with a BDI_CAP_STRICTLIMIT-backing device, using e.g. \nvm.dirty_bytes=(1<<32)*PAGE_SIZE so that dtc->thresh == (1<<32)"
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: mm/writeback: corrige la posible divisi\u00f3n por cero en wb_dirty_limits(), nuevamente (struct dirty_throttle_control *)-&gt;thresh es un largo sin firmar, pero se pasa como argumento del divisor u32 a div_u64(). En arquitecturas donde la longitud sin firmar es de 64 bytes, el argumento se truncar\u00e1 impl\u00edcitamente. Utilice div64_u64() en lugar de div_u64() para que el valor utilizado en la comprobaci\u00f3n \"\u00bfEs esta una divisi\u00f3n segura\" sea el mismo que el divisor? Adem\u00e1s, elimine la conversi\u00f3n redundante del numerador a u64, ya que eso deber\u00eda suceder impl\u00edcitamente. Esto ser\u00eda dif\u00edcil de explotar en el dominio memcg, dado el uso de la aritm\u00e9tica basada en proporciones domain_drity_limits(), pero es mucho m\u00e1s f\u00e1cil en el dominio de reescritura global con un dispositivo de respaldo BDI_CAP_STRICTLIMIT, usando, por ejemplo, vm.dirty_bytes=(1&lt;&lt;32)*PAGE_SIZE de modo que dtc-&gt;thresh == (1&lt;&lt;32)"
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/000099d71648504fb9c7a4616f92c2b70c3e44ec",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/145faa3d03688cbb7bbaaecbd84c01539852942c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/16b1025eaa8fc223ab4273ece20d1c3a4211a95d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/1f12e4b3284d6c863f272eb2de0d4248ed211cf4",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/23a28f5f3f6ca1e4184bd0e9631cd0944cf1c807",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/253f9ea7e8e53a5176bd80ceb174907b10724c1a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2820005edae13b140f2d54267d1bd6bb23915f59",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5099871b370335809c0fd1abad74d9c7c205d43f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/65977bed167a92e87085e757fffa5798f7314c9f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/81e7d2530d458548b90a5c5e76b77ad5e5d1c0df",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9319b647902cbd5cc884ac08a8a6d54ce111fc78",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c593d26fb5d577ef31b6e49a31e08ae3ebc1bc1e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cbbe17a324437c0ff99881a3ee453da45b228a00",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ec18ec230301583395576915d274b407743d8f6c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f6620df12cb6bdcad671d269debbb23573502f9d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}