validate_ntransact(char *buf, char **ppparm, char **ppdata,
		   __u32 *pparmlen, __u32 *pdatalen)
{
	char *end_of_smb;
	__u32 data_count, data_offset, parm_count, parm_offset;
	struct smb_com_ntransact_rsp *pSMBr;
	u16 bcc;

	*pdatalen = 0;
	*pparmlen = 0;

	if (buf == NULL)
		return -EINVAL;

	pSMBr = (struct smb_com_ntransact_rsp *)buf;

	bcc = get_bcc(&pSMBr->hdr);
	end_of_smb = 2 /* sizeof byte count */ + bcc +
			(char *)&pSMBr->ByteCount;

	data_offset = le32_to_cpu(pSMBr->DataOffset);
	data_count = le32_to_cpu(pSMBr->DataCount);
	parm_offset = le32_to_cpu(pSMBr->ParameterOffset);
	parm_count = le32_to_cpu(pSMBr->ParameterCount);

	*ppparm = (char *)&pSMBr->hdr.Protocol + parm_offset;
	*ppdata = (char *)&pSMBr->hdr.Protocol + data_offset;

	/* should we also check that parm and data areas do not overlap? */
	if (*ppparm > end_of_smb) {
		cFYI(1, "parms start after end of smb");
		return -EINVAL;
	} else if (parm_count + *ppparm > end_of_smb) {
		cFYI(1, "parm end after end of smb");
		return -EINVAL;
	} else if (*ppdata > end_of_smb) {
		cFYI(1, "data starts after end of smb");
		return -EINVAL;
	} else if (data_count + *ppdata > end_of_smb) {
		cFYI(1, "data %p + count %d (%p) past smb end %p start %p",
			*ppdata, data_count, (data_count + *ppdata),
			end_of_smb, pSMBr);
		return -EINVAL;
	} else if (parm_count + data_count > bcc) {
		cFYI(1, "parm count and data count larger than SMB");
		return -EINVAL;
	}
	*pdatalen = data_count;
	*pparmlen = parm_count;
	return 0;
}

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.