Keflavik Airport's (the main airport in Iceland) website states this:
Examples of goods subject to an importation ban:
Narcotics and dangerous drugs
Chewing tobacco and snuff
Uncooked meat products
In general, the condition for importing meat products is that
they be fully cooked or tinned. Smoking, salting or drying without
cooking is not sufficient. For example, the import of bacon, sausages
(salami, meat sausages and all kinds of smoked, uncooked sausages),
smoked saddle of pork and poultry is prohibited.
Uncooked milk and raw eggs
Various types of weapons
If you're departing from Iceland with these canned goods, that should not be an issue. I went to Iceland this summer, and someone in the line next to me checked a styrofoam box of fish, which the agent didn't seem to have a problem with. I'm sure he had issues at US customs, though.