If you've landed on m.odnoklassniki.ru, you're being sent to OK.ru, the current home of the Odnoklassniki social network. This isn't a scam or a fake: the domain has been around for 16 years and carries all the security markings you'd expect from a major platform. It's simply an old mobile address that the company retired after rebranding.
For a social media site, the key question is whether you'll end up somewhere legitimate. Here, the redirect is transparent and the destination is clearly OK.ru. That said, always check the address bar after any redirect, because phishing sites sometimes mimic this pattern. But in this case, everything checks out: clean blacklists, a valid certificate, and a hosting setup that matches the VK group that runs OK.ru.
In short, m.odnoklassniki.ru is a safe stepping stone, not a destination. If you're looking for Odnoklassniki, this will get you there without risk.