I think it's something on the order of 250 and held for a certain length of time. Usually a pressure cooking scenario for commercial and home canning. Also depends on the acidity. But garlic and oil is a recurring source as so many people do it.
Jeff Smith used to advocate a similar method to yours on his cooking shows. Reader's Digest printed a similar recipe once then issued a mass retraction.
Helen Witty who mostly writes pantry cookbooks goes over this in her books. Her recommended solution is to roast the garlic, mash into a paste, then freeze it. Then mix up SMALL amounts of garlic and oil intended to be quickly used up, always stored refrigerated. Refrigeration does buy you some protection as that retards bacterial growth.
There is also a risk with herb infused oils. Again, a wet ingredient covered in oil creating an anaerobic environment. Do it in small batches you'll use quickly. Herb vinegars are fine. They're oxygenated and acidic enough to prevent botulism. Except maybe rice vinegar at 1.5%? Not sure about the rice vinegar.
There were three threads on this topic when Harold McGee had a brief guest appearance here.ChefTalk Cooking Forums - Search Results
So how do the commercial makers produce garlic oil? With industrial methods to guarantee safety, extractives and other pasteurization type processes.