Method for updating stored information and apparatus

A method for updating stored information and an apparatus. A controller performs error correction code (ECC) decoding on stored data information based on the stored data information and stored ECC check information to generate an error-corrected codeword, where the error-corrected codeword includes error-corrected data information. The controller generates candidate to-be-written data information based on the error-corrected data information and a data update indication. The controller performs a mask operation on the candidate to-be-written data information based on the stored data information, and writes unmasked content in the candidate to-be-written data information into a memory.