CVE-2024-57881

Summary

In the Linux kernel, the following vulnerability has been resolved:

mm/page_alloc: don't call pfn_to_page() on possibly non-existent PFN in split_large_buddy()

In split_large_buddy(), we might call pfn_to_page() on a PFN that might not exist. In corner cases, such as when freeing the highest pageblock in the last memory section, this could result with CONFIG_SPARSEMEM && !CONFIG_SPARSEMEM_EXTREME in __pfn_to_section() returning NULL and and __section_mem_map_addr() dereferencing that NULL pointer.

Let's fix it, and avoid doing a pfn_to_page() call for the first iteration, where we already have the page.

So far this was found by code inspection, but let's just CC stable as the fix is easy.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxfd919a85cd55be5d00a6a7372071f44c8eafb825 < 4234ca9884bcae9e48ed38652d91696ad5cd591daffected
LinuxLinuxfd919a85cd55be5d00a6a7372071f44c8eafb825 < faeec8e23c10bd30e8aa759a2eb3018dae00f924affected
LinuxLinux6.10affected
LinuxLinux0 < 6.10unaffected
LinuxLinux6.12.7 <= 6.12.*unaffected
LinuxLinux6.13 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References