Perhaps i can clear the air here.
In Sabah, if both of your parents are Chinese origin, then u r not a bumiputera, If one of your parents are Kadazan/Dusun, and mix with other non bumi races, i.e. Chinese, then u r considered a Sino Kadazan, who is also grouped as bumiputera. The bottom line is either one of the parents or grandparents need to be a Native. Most of the SIno Kadazan has Chinese Name, usually "sijil anaka negeri" is the evidence to prove them as bumiputera.
In the case of Sarawak, both parents need to be Native then only classified as Bumiputera. Few years ago, we have one case, Father Iban with Chinese Mother, the dotter was rejected to enter Uitm, and getting JPA scholarship becoz one of the parents are not a bumi. It is stated in the Constituition, Perlembagaan Akta 163.
For the case of Semenanjung. It is like Sabah. As long as one of your parents/grandparents are Bumi, then the children are Bumi (In the PNB's context), i have come accross in some states, like in Melaka & in Penang, they do not recognise Orang Asli/ Kadazan/Iban as bumi when they purchase the properties in these states. Thus they do not qualified for bumi discount. On the other hand, if u r a converted muslim, say Chi Muslim, Indian Muslim, then u r eligible for bumi disocunt.
In shiort, there are still many grey areas in the classiification of bumiputera, some states follow root of family origin, some states follow religion.