Brazil boss Manolo Menezes has included defender Silva, 27, as one of his over-age players, while striker Pato, 23, is fully eligible.
The Rossoneri announced the news on their official website.
The calls are not entirely unexpected as the Serie A season does not start until September.
The Olympic football tournament takes place at venues all over Britain and runs from July 26 to August 11.
Brazil have been drawn in Group C with Egypt, Belarus and New Zealand.
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