CVE-2026-31436: Linux内核IDXD驱动空指针引用漏洞

/* * Conceptual Proof of Concept for CVE-2026-31436 * This snippet demonstrates the logic error in llist_abort_desc(). * Triggering this requires access to the IDXD device interface. */ #include <linux/module.h> #include <linux/kernel.h> // Mock structures to represent the kernel code context struct desc { struct list_head node; int status; }; void complete_desc(struct desc *d) { // Function to complete a descriptor if (!d) { printk(KERN_ALERT "Triggering NULL pointer dereference!\n"); // panic("PoC Trigger"); } } // Vulnerable function logic reconstruction void llist_abort_desc_vulnerable(struct list_head *flist, struct desc *found) { struct desc *d, *tmp; // Simulate list traversal list_for_each_entry_safe(d, tmp, flist, node) { // ... logic processing ... /* * VULNERABILITY: The code completes 'found' instead of 'd'. * If 'found' is NULL (common in some error paths), this crashes the kernel. */ complete_desc(found); // Bug: Should be complete_desc(d); } } // Module initialization (for demonstration) int init_module(void) { printk(KERN_INFO "CVE-2026-31436 PoC Loaded\n"); return 0; } void cleanup_module(void) { printk(KERN_INFO "CVE-2026-31436 PoC Unloaded\n"); } MODULE_LICENSE("GPL");