Is it permissible to lend money to a friend for investment, on condition that he returns the exact amount without increase or decrease, while the friend keeps all the profit?

Dealing with the shares of the aforementioned bank depends on the permissibility of investing in it. If investing in its shares is permissible, then there is no objection to entrusting money to it as Mudarabah (profit-sharing) or a loan. However, if its shares are impermissible, then it is not permissible to invest in them, nor is it permissible to give money to someone who intends to invest it in them, as that would be a cooperation in sin.