CVE-2026-31767 Linux内核i915驱动除零拒绝服务漏洞

/* * PoC Simulation for CVE-2026-31767 * This code simulates the logic error leading to a division by zero. * Trigger: Loading the i915 driver on affected hardware (e.g., Huawei Matebook E) * in command mode. */ #include <stdio.h> #include <stdlib.h> // Simulated structure for display timings struct display_timing { int htotal; int pixel_clock; // in kHz }; // Vulnerable function logic simulation void calculate_vtotal(struct display_timing *timing) { // Simulate DSC adjustment in command mode (the bug) // In command mode, this adjustment makes htotal extremely small printf("[+] Applying DSC timing adjustment in Command Mode...\n"); timing->htotal = 10; // Abnormally small value due to bug printf("[+] Adjusted htotal: %d\n", timing->htotal); // Calculate line time in microseconds // Logic: (htotal * 1000) / pixel_clock // If htotal is too small, integer division might result in 0 unsigned int line_time_us = (timing->htotal * 1000) / timing->pixel_clock; printf("[+] Calculated line_time_us: %u\n", line_time_us); // The crash happens here when determining vtotal // vtotal calculation typically involves dividing by line_time_us if (line_time_us == 0) { printf("[!] EXPLOIT TRIGGERED: Division by zero! Kernel Panic.\n"); // int vtotal = 1000000 / line_time_us; // This would crash the kernel } else { int vtotal = 1000000 / line_time_us; printf("[-] Safe execution. vtotal: %d\n", vtotal); } } int main() { printf("CVE-2026-31767 PoC Simulation\n"); printf("-------------------------------\n"); struct display_timing timing; timing.pixel_clock = 150000; // Typical pixel clock // Scenario: System enters command mode calculate_vtotal(&timing); return 0; }