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().

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/8b671fe1a879923ecfb72dda6caf01460dd885ef	Patch
https://git.kernel.org/stable/c/8de7bf77f21068a5f602bb1e59adbc5ab533509d	Patch
https://git.kernel.org/stable/c/a39e38be632f0e1c908d70d1c9cd071c03faf895	Patch
https://git.kernel.org/stable/c/d6510f234c7d117790397f9bb150816b0a954a04	Patch

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

No history.

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

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