Vulnerabilities > CVE-2024-42131 - Integer Overflow or Wraparound vulnerability in Linux Kernel
Summary
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 PAGE_SIZE 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 dirty_bytes / dirty_background_bytes interfaces we can just refuse to set so large limits. For dirty_ratio / dirty_background_ratio 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 UINT_MAX. This is root-only triggerable problem which occurs when the operator sets dirty limits to >16 TB.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Forced Integer Overflow This attack forces an integer variable to go out of range. The integer variable is often used as an offset such as size of memory allocation or similarly. The attacker would typically control the value of such variable and try to get it out of range. For instance the integer in question is incremented past the maximum possible value, it may wrap to become a very small, or negative number, therefore providing a very incorrect value which can lead to unexpected behavior. At worst the attacker can execute arbitrary code.
References
- https://git.kernel.org/stable/c/7a49389771ae7666f4dc3426e2a4594bf23ae290
- https://git.kernel.org/stable/c/a25e8536184516b55ef89ab91dd2eea429de28d2
- https://git.kernel.org/stable/c/c83ed422c24f0d4b264f89291d4fabe285f80dbc
- https://git.kernel.org/stable/c/bd16a7ee339aef3ee4c90cb23902afb6af379ea0
- https://git.kernel.org/stable/c/8e0b5e7f2895eccef5c2a0018b589266f90c4805
- https://git.kernel.org/stable/c/385d838df280eba6c8680f9777bfa0d0bfe7e8b2
- https://git.kernel.org/stable/c/2b2d2b8766db028bd827af34075f221ae9e9efff
- https://git.kernel.org/stable/c/4d3817b64eda07491bdd86a234629fe0764fb42a