Foreign executives in China are upset at a new rule that allows authorities to hold passports for up to 15 working days when processing and renewing residency permits, saying it could disrupt essential business travel within China and abroad. The changes are evidence to those who argue China is becoming a harder place to do business, especially following a wave of antitrust investigations that some executives contend have singled out foreign firms. The increased processing time from five working days had prompted a “flood” of complaints from the expatriate community, said Gary Chodorow, a Beijing-based immigration lawyer at Hong Law Offices. The new rules took effect on July 1. Chinese officials have said they aim to deal with the rising flow of foreigners coming to China and to protect national security and social order.