CVE-2024-42316

In the Linux kernel, the following vulnerability has been resolved: mm/mglru: fix div-by-zero in vmpressure_calc_level() evict_folios() uses a second pass to reclaim folios that have gone through page writeback and become clean before it finishes the first pass, since folio_rotate_reclaimable() cannot handle those folios due to the isolation. The second pass tries to avoid potential double counting by deducting scan_control->nr_scanned. However, this can result in underflow of nr_scanned, under a condition where shrink_folio_list() does not increment nr_scanned, i.e., when folio_trylock() fails. The underflow can cause the divisor, i.e., scale=scanned+reclaimed in vmpressure_calc_level(), to become zero, resulting in the following crash: [exception RIP: vmpressure_work_fn+101] process_one_work at ffffffffa3313f2b Since scan_control->nr_scanned has no established semantics, the potential double counting has minimal risks. Therefore, fix the problem by not deducting scan_control->nr_scanned in evict_folios().
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

22 Aug 2024, 15:52

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5
First Time Linux
Linux linux Kernel
References () https://git.kernel.org/stable/c/8b671fe1a879923ecfb72dda6caf01460dd885ef - () https://git.kernel.org/stable/c/8b671fe1a879923ecfb72dda6caf01460dd885ef - Patch
References () https://git.kernel.org/stable/c/8de7bf77f21068a5f602bb1e59adbc5ab533509d - () https://git.kernel.org/stable/c/8de7bf77f21068a5f602bb1e59adbc5ab533509d - Patch
References () https://git.kernel.org/stable/c/a39e38be632f0e1c908d70d1c9cd071c03faf895 - () https://git.kernel.org/stable/c/a39e38be632f0e1c908d70d1c9cd071c03faf895 - Patch
References () https://git.kernel.org/stable/c/d6510f234c7d117790397f9bb150816b0a954a04 - () https://git.kernel.org/stable/c/d6510f234c7d117790397f9bb150816b0a954a04 - Patch
CWE CWE-369
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

19 Aug 2024, 12:59

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm/mglru: corrige div-by-zero en vmpression_calc_level() evict_folios() utiliza una segunda pasada para recuperar las publicaciones que han pasado por la reescritura de páginas y quedan limpias antes de finalizar el primer pase, ya que folio_rotate_reclaimable() no puede manejar esos folios debido al aislamiento. El segundo paso intenta evitar un posible doble conteo deduciendo scan_control->nr_scanned. Sin embargo, esto puede resultar en un desbordamiento insuficiente de nr_scanned, bajo una condición en la que Shrink_folio_list() no incrementa nr_scanned, es decir, cuando falla folio_trylock(). El desbordamiento insuficiente puede causar que el divisor, es decir, escala=escaneado+reclamado en vmpression_calc_level(), se convierta en cero, lo que resulta en el siguiente bloqueo: [excepción RIP: vmpression_work_fn+101] Process_one_work en ffffffffa3313f2b Dado que scan_control->nr_scanned no tiene una semántica establecida, la posible doble contabilización tiene riesgos mínimos. Por lo tanto, solucione el problema no deduciendo scan_control->nr_scanned en evict_folios().

17 Aug 2024, 09:15

Type Values Removed Values Added
New CVE

Information

Published : 2024-08-17 09:15

Updated : 2024-08-22 15:52


NVD link : CVE-2024-42316

Mitre link : CVE-2024-42316

CVE.ORG link : CVE-2024-42316


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-369

Divide By Zero