All that is stated for linear exams is that a scaled score of 700 is required to pass.
From that you can infer that even if you have not answered all the questions, as long as you have enough correct answers from the questions you did complete then you can still pass the exam. It's certainly not stated anywhere you have to answer all questions or you automatically fail.
Managing your time in the exams is important though, and with linear exams you do have the ability to mark questions for review and go back to questions (although I am not a fan doing that), so try not to spend too much time on individual questions keeping the bigger picture of the whole exam in mind.
ISC2 linear exams tend to be 125 questions in 3 hours these days (not including the non-English CISSP exam), so that gives you an average of 86.4 seconds to spend on each question. Inevitably some questions will be longer / harder than others so you may be able to answer some very quickly giving you extra time to spend on the more difficult ones.