The Mein Kampf is a perennial best seller in the Arab world mostly due to its anti-Semitism, which obviously became very popular in said market after the establishment of Israel. And it's not like the Soviets are going to let ideology get in the way of a very nice geopolitical arrangement.
The Soviet-Arab alliance was in many ways a simple "the enemy of my enemy is my friend." The Arabs opposed Israel. The West supported Israel, so the Arabs were opposed to the West. Soviets and the Arabs were opposed to the West, and seeing as how the Soviets were not only opposed to the West, but both the foremost proponents of decolonization and were a nuclear power, it was a nice deal for the Arabs.