SMB2_query_info_init(struct cifs_tcon *tcon, struct smb_rqst *rqst,
		     u64 persistent_fid, u64 volatile_fid,
		     u8 info_class, u8 info_type, u32 additional_info,
		     size_t output_len, size_t input_len, void *input)
{
	struct smb2_query_info_req *req;
	struct kvec *iov = rqst->rq_iov;
	unsigned int total_len;
	int rc;

	rc = smb2_plain_req_init(SMB2_QUERY_INFO, tcon, (void **) &req,
			     &total_len);
	if (rc)
		return rc;

	req->InfoType = info_type;
	req->FileInfoClass = info_class;
	req->PersistentFileId = persistent_fid;
	req->VolatileFileId = volatile_fid;
	req->AdditionalInformation = cpu_to_le32(additional_info);

	req->OutputBufferLength = cpu_to_le32(output_len);
	if (input_len) {
		req->InputBufferLength = cpu_to_le32(input_len);
		/* total_len for smb query request never close to le16 max */
		req->InputBufferOffset = cpu_to_le16(total_len - 1);
		memcpy(req->Buffer, input, input_len);
	}

	iov[0].iov_base = (char *)req;
	/* 1 for Buffer */
	iov[0].iov_len = total_len - 1 + input_len;
	return 0;
}

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.