Town boss Mick McCarthy hopes to make McGoldrick's move a permanent one in the summer, and he hopes the double deal will help lift them away from their position five points above the relegation zone.
He was looking for attacking options in the wake of DJ Campbell's return to QPR and identified McGoldrick, who scored 17 times in 26 appearances for League One side Coventry.
"David dropped down a level to play for Coventry on loan over the first half of the season and did really well," McCarthy said.
"He was the leading scorer in League One with 16 goals so we are signing a player at the top of his form. He's a good player who we have been watching and it's deal that we are looking to lead to a permanent one."
McLean has found goals and playing time harder to come by, scoring three times in 16 outings, but McCarthy feels he will also prove a valuable addition.
"I tried to sign him for Wolves a long time ago so I know about his qualities," the Town boss added.
"He will bring pace, power and athleticism to the side and I'm delighted that we have managed to get both of them."