CVE-2026-31784 Linux内核drm/xe/pxp逻辑错误漏洞

/* * Conceptual Proof of Concept (PoC) for CVE-2026-31784 * This C code demonstrates the logical flaw present in the Linux Kernel's drm/xe/pxp module. * The vulnerable function fails to clear a restart flag after jumping back, * causing an infinite loop. */ #include <stdio.h> #include <stdbool.h> void simulated_vulnerable_function() { bool restart_flag = false; int counter = 0; start: printf("Function started. Counter: %d\n", counter); // Simulate some internal logic if (counter > 0) { printf("Checking restart flag...\n"); // VULNERABILITY: In the actual CVE, the code path that leads to 'start' // does not reset 'restart_flag'. If it remains true, we loop forever. if (restart_flag) { printf("Restart flag is still TRUE. Jumping back...\n"); goto start; } } // Simulate a condition that triggers a restart (e.g., initialization retry) if (counter == 0) { restart_flag = true; // Set the flag counter++; printf("Condition met. Setting restart flag and jumping...\n"); goto start; // EXPLOIT: The jump happens, but the flag remains true for the next iteration. } printf("Function finished normally.\n"); } int main() { printf("Starting PoC simulation for CVE-2026-31784...\n"); simulated_vulnerable_function(); return 0; }