SMB2_QFS_attr(const unsigned int xid, struct cifs_tcon *tcon,
	      u64 persistent_fid, u64 volatile_fid, int level)
{
	struct smb_rqst rqst;
	struct smb2_query_info_rsp *rsp = NULL;
	struct kvec iov;
	struct kvec rsp_iov;
	int rc = 0;
	int resp_buftype, max_len, min_len;
	struct cifs_ses *ses = tcon->ses;
	unsigned int rsp_len, offset;
	int flags = 0;

	if (level == FS_DEVICE_INFORMATION) {
		max_len = sizeof(FILE_SYSTEM_DEVICE_INFO);
		min_len = sizeof(FILE_SYSTEM_DEVICE_INFO);
	} else if (level == FS_ATTRIBUTE_INFORMATION) {
		max_len = sizeof(FILE_SYSTEM_ATTRIBUTE_INFO);
		min_len = MIN_FS_ATTR_INFO_SIZE;
	} else if (level == FS_SECTOR_SIZE_INFORMATION) {
		max_len = sizeof(struct smb3_fs_ss_info);
		min_len = sizeof(struct smb3_fs_ss_info);
	} else if (level == FS_VOLUME_INFORMATION) {
		max_len = sizeof(struct smb3_fs_vol_info) + MAX_VOL_LABEL_LEN;
		min_len = sizeof(struct smb3_fs_vol_info);
	} else {
		cifs_dbg(FYI, "Invalid qfsinfo level %d\n", level);
		return -EINVAL;
	}

	rc = build_qfs_info_req(&iov, tcon, level, max_len,
				persistent_fid, volatile_fid);
	if (rc)
		return rc;

	if (smb3_encryption_required(tcon))
		flags |= CIFS_TRANSFORM_REQ;

	memset(&rqst, 0, sizeof(struct smb_rqst));
	rqst.rq_iov = &iov;
	rqst.rq_nvec = 1;

	rc = cifs_send_recv(xid, ses, &rqst, &resp_buftype, flags, &rsp_iov);
	cifs_small_buf_release(iov.iov_base);
	if (rc) {
		cifs_stats_fail_inc(tcon, SMB2_QUERY_INFO_HE);
		goto qfsattr_exit;
	}
	rsp = (struct smb2_query_info_rsp *)rsp_iov.iov_base;

	rsp_len = le32_to_cpu(rsp->OutputBufferLength);
	offset = le16_to_cpu(rsp->OutputBufferOffset);
	rc = smb2_validate_iov(offset, rsp_len, &rsp_iov, min_len);
	if (rc)
		goto qfsattr_exit;

	if (level == FS_ATTRIBUTE_INFORMATION)
		memcpy(&tcon->fsAttrInfo, offset
			+ (char *)rsp, min_t(unsigned int,
			rsp_len, max_len));
	else if (level == FS_DEVICE_INFORMATION)
		memcpy(&tcon->fsDevInfo, offset
			+ (char *)rsp, sizeof(FILE_SYSTEM_DEVICE_INFO));
	else if (level == FS_SECTOR_SIZE_INFORMATION) {
		struct smb3_fs_ss_info *ss_info = (struct smb3_fs_ss_info *)
			(offset + (char *)rsp);
		tcon->ss_flags = le32_to_cpu(ss_info->Flags);
		tcon->perf_sector_size =
			le32_to_cpu(ss_info->PhysicalBytesPerSectorForPerf);
	} else if (level == FS_VOLUME_INFORMATION) {
		struct smb3_fs_vol_info *vol_info = (struct smb3_fs_vol_info *)
			(offset + (char *)rsp);
		tcon->vol_serial_number = vol_info->VolumeSerialNumber;
		tcon->vol_create_time = vol_info->VolumeCreationTime;
	}

qfsattr_exit:
	free_rsp_buf(resp_buftype, rsp_iov.iov_base);
	return rc;
}

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.