ISUID
((DIP(dp, di_mode) & (ISGID | ISUID)) == 0 &&
ip->i_e2fs_mode &= ~(ISUID | ISGID);
ip->i_e2fs_mode &= ~ISUID;
DIP_ASSIGN(ip, mode, DIP(ip, mode) & ~(ISUID | ISGID));
DIP_AND(ip, mode, ~ISUID);