Is there any proof to these allegations? We all know how bad Soviets fucked up Afghanistan, but we should accept everything with proof, considering there was a constant propaganda battle between ISI, CIA and KGB regarding the war in Afghanistan. Does your allegations have anything to do with the fact that Pakistan and Soviets stood on the opposite sides?
About war crimes, for example I read, on a daily basis, about crimes of ISI regarding Baloochs and others, kidnappings, mass graves, tortures, I certainly don't believe them when I see them without proof, but one thing is for sure, most secret services in the world have made their hands pretty dirty.
Russians are no exceptions, we can conclude with confidence that if Soviets had not attacked Afghanistan, not only we would see another completely different Afghanistan today, but also a different Middle East. U.S and Soviets are the main culprits for the fucked up situation in region.
But, if Russians are killing ISIS and other terrorists for whatever reason, we shouldn't stop them, they are doing a good thing, regardless of their past.