CVE-2026-31564: Linux内核LoongArch KVM地址计算漏洞

/* * PoC Concept for CVE-2026-31564 * This simulates the logic error in address calculation. * Vulnerable kernel code performs arithmetic on u64 before casting. */ #include <stdio.h> #include <stdint.h> // Simulate the vulnerable logic void vulnerable_access(uint64_t base, uint64_t offset) { // Vulnerable: u64 arithmetic addition (context dependent) // If 'offset' is treated as byte offset, this might be fine, // but if the logic expects pointer alignment or specific casting, it fails. uint64_t bad_addr_val = base + offset; void *bad_ptr = (void *)bad_addr_val; printf("[VULN] Calculated Address: %p\n", bad_ptr); } // Simulate the fixed logic void fixed_access(uint64_t base, uint64_t offset) { // Fix: Cast to void* first, then add offset (pointer arithmetic) void *good_ptr = (void *)base + offset; printf("[FIX] Calculated Address: %p\n", good_ptr); } int main() { uint64_t base = 0x80000000; uint64_t offset = 0x100; vulnerable_access(base, offset); fixed_access(base, offset); return 0; }