To remove stain of rust from clothes, rub a piece of tomato on the stained portion of the outfit. Then wash it as usual, the stain will disappear. If the stain is stubborn, repeat the process.

Alternate suggestion

Chemically, acids are the preferred way to remove rust stains. Believe it or not lemon juice (citric acid), or the "stronger" white vinegar (acetic acid) are mild ACIDS which may resolve the problem. In the corner of an affected area, I would test both acids to determine which one is most effective. Apply the acid with the clean sponge side of a white, nylon scrub pad backed sponge (available at supermarkets). Agitate with the scrub pad side. Rust stains are the result of oxidation. Rinse thoroughly afterwards and blot dry.

Test an inconspicuous spot first to make sure it doesn't fade the fabric. A user who had rust stains on a pair of white pants cleaned them using hand cleaner and a nail brush.