CVE-2024-57945: Linux Kernel
High severity, CVSS 7.1. EPSS: 0.2% chance of exploitation in the next 30 days.
In the Linux kernel, the following vulnerability has been resolved: riscv: mm: Fix the out of bound issue of vmemmap address In sparse vmemmap model, the virtual address of vmemmap is calculated as: ((struct page *)VMEMMAP_START - (phys_ram_base >> PAGE_SHIFT)). And the struct page's va can be calculated with an offset: (vmemmap + (pfn)). However, when initializing struct pages, kernel actually starts from the first page from the same section that phys_ram_base belongs to. If the first page's physical address is not (phys_ram_base >> PAGE_SHIFT), then we get an va below VMEMMAP_START when calculating va for it's struct page. For example, if phys_ram_base starts from 0x82000000 with pfn 0x82000, the first page in the same section is actually pfn 0x80000. During init_unavailable_range(), we will initialize struct page for pfn 0x80000 with virtual address ((struct page *)VMEMMAP_START - 0x2000), which is below VMEMMAP_START as well as PCI_IO_END. This commit fixes this bug by introducing a new variable 'vmemmap_start_pfn' which is aligned with memory section size and using it to calculate vmemmap address instead of phys_ram_base.
Affected products
- Linux Linux Kernel: from 5.10.212, before 5.11 (fixed in 5.11); from 5.15.151, before 5.16 (fixed in 5.16); from 6.1.81, before 6.1.140 (fixed in 6.1.140); from 6.6.21, before 6.6.72 (fixed in 6.6.72); from 6.7.9, before 6.8 (fixed in 6.8); from 6.8.1, before 6.12.10 (fixed in 6.12.10); …
Published 2025-01-21. Last modified 2026-08-04.