Looking at Russia's official naval logistics force wouldn't give you the idea that Russia could supply their Syria war effort:
Dozens of Russian warships, auxiliary naval cargo ships and sometimes even submarines have passed through the Bosphorus Strait, northbound and southbound. Every month since Russia stepped up operations inside Syria last year, according to maritime experts. ...
Mikhail Voitenko, Russian maritime expert and editor of the Maritime Bulletin website, said that the supplies delivered via the Bosphorus were a "lifeline" for the Syria campaign.
"Without the Syrian Express, the Syrian campaign would choke in days or weeks."
The auxiliary naval cargo ships are the interesting part:
In a move reminiscent of early 1942 in the Pacific, when American officers were ordered to buy or charter any ocean going shipping they could find to aid in mobilizing forces to halt the Japanese advance, Russia carried out a similar program along the Black Sea coast starting in April 2015. Without any publicity the Russian government told ship brokers to buy up any seaworthy shipping they could find and turn them over to Russian “shipping companies” where the ships were given new names, Russian crews and plenty of work moving military cargo from Russia to Syria.
Which is why I don't assume, as so many still do today, that China--with a massive civilian shipping fleet--can't invade Taiwan just because China doesn't have a large force of dedicated amphibious warfare ships.