CVE-2024-26924

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_pipapo: do not free live element Pablo reports a crash with large batches of elements with a back-to-back add/remove pattern. Quoting Pablo: add_elem("00000000") timeout 100 ms ... add_elem("0000000X") timeout 100 ms del_elem("0000000X") <---------------- delete one that was just added ... add_elem("00005000") timeout 100 ms 1) nft_pipapo_remove() removes element 0000000X Then, KASAN shows a splat. Looking at the remove function there is a chance that we will drop a rule that maps to a non-deactivated element. Removal happens in two steps, first we do a lookup for key k and return the to-be-removed element and mark it as inactive in the next generation. Then, in a second step, the element gets removed from the set/map. The _remove function does not work correctly if we have more than one element that share the same key. This can happen if we insert an element into a set when the set already holds an element with same key, but the element mapping to the existing key has timed out or is not active in the next generation. In such case its possible that removal will unmap the wrong element. If this happens, we will leak the non-deactivated element, it becomes unreachable. The element that got deactivated (and will be freed later) will remain reachable in the set data structure, this can result in a crash when such an element is retrieved during lookup (stale pointer). Add a check that the fully matching key does in fact map to the element that we have marked as inactive in the deactivation step. If not, we need to continue searching. Add a bug/warn trap at the end of the function as well, the remove function must not ever be called with an invisible/unreachable/non-existent element. v2: avoid uneeded temporary variable (Stefano)
Configurations

No configuration.

History

21 Nov 2024, 09:03

Type Values Removed Values Added
References
  • () https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html -
References () https://git.kernel.org/stable/c/14b001ba221136c15f894577253e8db535b99487 - () https://git.kernel.org/stable/c/14b001ba221136c15f894577253e8db535b99487 -
References () https://git.kernel.org/stable/c/3cfc9ec039af60dbd8965ae085b2c2ccdcfbe1cc - () https://git.kernel.org/stable/c/3cfc9ec039af60dbd8965ae085b2c2ccdcfbe1cc -
References () https://git.kernel.org/stable/c/41d8fdf3afaff312e17466e4ab732937738d5644 - () https://git.kernel.org/stable/c/41d8fdf3afaff312e17466e4ab732937738d5644 -
References () https://git.kernel.org/stable/c/7a1679e2d9bfa3b5f8755c2c7113e54b7d42bd46 - () https://git.kernel.org/stable/c/7a1679e2d9bfa3b5f8755c2c7113e54b7d42bd46 -
References () https://git.kernel.org/stable/c/e3b887a9c11caf8357a821260e095f2a694a34f2 - () https://git.kernel.org/stable/c/e3b887a9c11caf8357a821260e095f2a694a34f2 -
References () https://git.kernel.org/stable/c/ebf7c9746f073035ee26209e38c3a1170f7b349a - () https://git.kernel.org/stable/c/ebf7c9746f073035ee26209e38c3a1170f7b349a -

05 Nov 2024, 10:16

Type Values Removed Values Added
References
  • {'url': 'https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html', 'source': '416baaa9-dc9f-4396-8d5f-8c081fb06d67'}

03 Jul 2024, 01:50

Type Values Removed Values Added
CWE CWE-476
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.9

25 Jun 2024, 22:15

Type Values Removed Values Added
References
  • () https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html -

03 May 2024, 06:15

Type Values Removed Values Added
References
  • {'url': 'https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4EZ6PJW7VOZ224TD7N4JZNU6KV32ZJ53/', 'source': '416baaa9-dc9f-4396-8d5f-8c081fb06d67'}
  • {'url': 'https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DAMSOZXJEPUOXW33WZYWCVAY7Z5S7OOY/', 'source': '416baaa9-dc9f-4396-8d5f-8c081fb06d67'}
  • {'url': 'https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GCBZZEC7L7KTWWAS2NLJK6SO3IZIL4WW/', 'source': '416baaa9-dc9f-4396-8d5f-8c081fb06d67'}
  • () https://git.kernel.org/stable/c/e3b887a9c11caf8357a821260e095f2a694a34f2 -

03 May 2024, 03:16

Type Values Removed Values Added
References
  • () https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4EZ6PJW7VOZ224TD7N4JZNU6KV32ZJ53/ -
  • () https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DAMSOZXJEPUOXW33WZYWCVAY7Z5S7OOY/ -
  • () https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GCBZZEC7L7KTWWAS2NLJK6SO3IZIL4WW/ -

28 Apr 2024, 12:15

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/14b001ba221136c15f894577253e8db535b99487 -
  • () https://git.kernel.org/stable/c/41d8fdf3afaff312e17466e4ab732937738d5644 -
  • () https://git.kernel.org/stable/c/7a1679e2d9bfa3b5f8755c2c7113e54b7d42bd46 -
  • () https://git.kernel.org/stable/c/ebf7c9746f073035ee26209e38c3a1170f7b349a -

25 Apr 2024, 13:18

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: nft_set_pipapo: no liberar elemento activo Pablo informa un bloqueo con grandes lotes de elementos con un patrón de agregar/eliminar consecutivos. Citando a Pablo: add_elem("00000000") timeout 100 ms ... add_elem("0000000X") timeout 100 ms del_elem("0000000X") &lt;---------------- elimina uno que se acaba de agregar... add_elem("00005000") tiempo de espera 100 ms 1) nft_pipapo_remove() elimina el elemento 0000000X Luego, KASAN muestra un símbolo. Al observar la función de eliminación, existe la posibilidad de que eliminemos una regla que se asigne a un elemento no desactivado. La eliminación se realiza en dos pasos: primero buscamos la clave k, devolvemos el elemento que se va a eliminar y lo marcamos como inactivo en la próxima generación. Luego, en un segundo paso, el elemento se elimina del conjunto/mapa. La función _remove no funciona correctamente si tenemos más de un elemento que comparte la misma clave. Esto puede suceder si insertamos un elemento en un conjunto cuando el conjunto ya contiene un elemento con la misma clave, pero la asignación del elemento a la clave existente ha expirado o no está activa en la próxima generación. En tal caso, es posible que la eliminación desasigne el elemento incorrecto. Si esto sucede, filtraremos el elemento no desactivado, se vuelve inalcanzable. El elemento que se desactivó (y se liberará más adelante) permanecerá accesible en la estructura de datos establecida, lo que puede provocar un bloqueo cuando dicho elemento se recupere durante la búsqueda (puntero obsoleto). Agregue una verificación de que la clave que coincide completamente de hecho se asigna al elemento que hemos marcado como inactivo en el paso de desactivación. Si no, debemos seguir buscando. Agregue también una trampa de error/advertencia al final de la función; la función de eliminación nunca debe llamarse con un elemento invisible/inalcanzable/inexistente. v2: evitar variables temporales innecesarias (Stefano)

25 Apr 2024, 06:15

Type Values Removed Values Added
New CVE

Information

Published : 2024-04-25 06:15

Updated : 2024-11-21 09:03


NVD link : CVE-2024-26924

Mitre link : CVE-2024-26924

CVE.ORG link : CVE-2024-26924


JSON object : View

Products Affected

No product.

CWE
CWE-476

NULL Pointer Dereference