CVE-2024-42131: mm: avoid overflows in dirty throttling logic
In the Linux kernel, the following vulnerability has been resolved:
mm: avoid overflows in dirty throttling logic
The dirty throttling logic is interspersed with assumptions that dirty limits in PAGESIZE units fit into 32-bit (so that various multiplications fit into 64-bits). If limits end up being larger, we will hit overflows, possible divisions by 0 etc. Fix these problems by never allowing so large dirty limits as they have dubious practical value anyway. For dirtybytes / dirtybackgroundbytes interfaces we can just refuse to set so large limits. For dirtyratio / dirtybackgroundratio it isn't so simple as the dirty limit is computed from the amount of available memory which can change due to memory hotplug etc. So when converting dirty limits from ratios to numbers of pages, we just don't allow the result to exceed UINTMAX.
This is root-only triggerable problem which occurs when the operator sets dirty limits to >16 TB.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-42131?
The severity of CVE-2024-42131 is classified as medium.
How do I fix CVE-2024-42131?
You can fix CVE-2024-42131 by upgrading to kernel versions 5.10.222 or later, 5.15.163 or later, 6.1.98 or later, or 6.6.39 or later.
What systems are affected by CVE-2024-42131?
CVE-2024-42131 affects various versions of the Linux kernel from versions prior to 5.10.222 up to 6.10.
Is CVE-2024-42131 being actively exploited?
As of now, there are no publicly reported exploits associated with CVE-2024-42131.
What are the potential impacts of CVE-2024-42131 if left unpatched?
If left unpatched, CVE-2024-42131 could potentially lead to system instability or performance issues due to flaws in the dirty throttling logic.