In A and the editions – except for one – there are no naturals before the 1st octave in this bar (nor a cautionary 
before c2 in the middle of the bar). The harmonic context clearly indicates Chopin's oversight, which is confirmed by his entry in FES. The mistake was overlooked by the revisers until GE5.
Compare the passage in the sources »
category imprint: Differences between sources
issues: GE revisions, Omission of current key accidentals, Last key signature sign
notation: Pitch