galore is from Irish Gaelic go leór "enough", which is from the particle go plus leór "enough". leór is from Old Irish lour, an alternation of roar, from the Proto-Celtic compound *ro-wero- "sufficiency". This is formed from the intensive prefix *ro- (from PIE *per-) and *wero- from PIE *wērh₂-o- "true, trustworthy".
*wērh₂-o- in Proto-Germanic became *wēra, then Old English wǣr "covenant, pledge". warlock is from Old English wǣrloga, the loga being related to Old English lēoȝan "to lie, deceive" (from PIE *leugʱ- "to lie"). So the etymological meaning of this word is "pledge-breaker". The Middle English warlow(e) was replaced by the Scots variant warlo(c)k.
*wērh₂-o- also became Latin vērus "true", and very.