Both are correct because both "some" and "any" specify an amount of the object you are talking about. If you ask someone "do you want __ sugar" and use any or some, chances are they're gonna understand what you're talking about either way.

Here, we would probably ask "Would you like sugar?"

Ernestina is correct. To state it another way, you aren't offering a specific amount of sugar, you're merely offering the sugar.

Grammatically, "Do you want some sugar?" is correct. When you ask a question with an expectation of yes as an answer, then, you should use "some". It's rare that you ask a question but expect "No" as an answer. That's why I don't believe "Do you want any sugar?" is right. Though in speaking English, both may be accepted.