fkie_cve-2024-50199
Vulnerability from fkie_nvd
Published
2024-11-08 06:15
Modified
2024-11-08 19:01
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: mm/swapfile: skip HugeTLB pages for unuse_vma I got a bad pud error and lost a 1GB HugeTLB when calling swapoff. The problem can be reproduced by the following steps: 1. Allocate an anonymous 1GB HugeTLB and some other anonymous memory. 2. Swapout the above anonymous memory. 3. run swapoff and we will get a bad pud error in kernel message: mm/pgtable-generic.c:42: bad pud 00000000743d215d(84000001400000e7) We can tell that pud_clear_bad is called by pud_none_or_clear_bad in unuse_pud_range() by ftrace. And therefore the HugeTLB pages will never be freed because we lost it from page table. We can skip HugeTLB pages for unuse_vma to fix it.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/417d5838ca73c6331ae2fe692fab6c25c00d9a0b
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6ec0fe3756f941f42f8c57156b8bdf2877b2ebaf
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7528c4fb1237512ee18049f852f014eba80bbe8d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ba7f982cdb37ff5a7739dec85d7325ea66fc1496
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/bed2b9037806c62166a0ef9a559a1e7e3e1275b8
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e41710f5a61aca9d6baaa8f53908a927dd9e7aa7
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/eb66a833cdd2f7302ee05d05e0fa12a2ca32eb87
Impacted products
Vendor Product Version


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{
   cveTags: [],
   descriptions: [
      {
         lang: "en",
         value: "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/swapfile: skip HugeTLB pages for unuse_vma\n\nI got a bad pud error and lost a 1GB HugeTLB when calling swapoff.  The\nproblem can be reproduced by the following steps:\n\n 1. Allocate an anonymous 1GB HugeTLB and some other anonymous memory.\n 2. Swapout the above anonymous memory.\n 3. run swapoff and we will get a bad pud error in kernel message:\n\n  mm/pgtable-generic.c:42: bad pud 00000000743d215d(84000001400000e7)\n\nWe can tell that pud_clear_bad is called by pud_none_or_clear_bad in\nunuse_pud_range() by ftrace.  And therefore the HugeTLB pages will never\nbe freed because we lost it from page table.  We can skip HugeTLB pages\nfor unuse_vma to fix it.",
      },
      {
         lang: "es",
         value: "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm/swapfile: omitir páginas HugeTLB para unuse_vma Obtuve un error pud incorrecto y perdí un HugeTLB de 1 GB al llamar a swapoff. El problema se puede reproducir mediante los siguientes pasos: 1. Asignar un HugeTLB anónimo de 1 GB y otra memoria anónima. 2. Intercambiar la memoria anónima anterior. 3. Ejecutar swapoff y obtendremos un error pud incorrecto en el mensaje del kernel: mm/pgtable-generic.c:42: bad pud 00000000743d215d(84000001400000e7) Podemos decir que pud_clear_bad es llamado por pud_none_or_clear_bad en unuse_pud_range() por ftrace. Y por lo tanto, las páginas HugeTLB nunca se liberarán porque las perdimos de la tabla de páginas. Podemos omitir las páginas HugeTLB para unuse_vma para solucionarlo.",
      },
   ],
   id: "CVE-2024-50199",
   lastModified: "2024-11-08T19:01:03.880",
   metrics: {},
   published: "2024-11-08T06:15:16.527",
   references: [
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         url: "https://git.kernel.org/stable/c/417d5838ca73c6331ae2fe692fab6c25c00d9a0b",
      },
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         url: "https://git.kernel.org/stable/c/6ec0fe3756f941f42f8c57156b8bdf2877b2ebaf",
      },
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         url: "https://git.kernel.org/stable/c/7528c4fb1237512ee18049f852f014eba80bbe8d",
      },
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         url: "https://git.kernel.org/stable/c/ba7f982cdb37ff5a7739dec85d7325ea66fc1496",
      },
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         url: "https://git.kernel.org/stable/c/bed2b9037806c62166a0ef9a559a1e7e3e1275b8",
      },
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         url: "https://git.kernel.org/stable/c/e41710f5a61aca9d6baaa8f53908a927dd9e7aa7",
      },
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         url: "https://git.kernel.org/stable/c/eb66a833cdd2f7302ee05d05e0fa12a2ca32eb87",
      },
   ],
   sourceIdentifier: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
   vulnStatus: "Awaiting Analysis",
}


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