The Secretary of Housing and Urban Development may sue and be sued only with respect to its functions under the United States Housing Act of 1937, as amended [42 U.S.C. 1437 et seq.], and title II of Public Law 671, Seventy-sixth Congress, approved June 28, 1940, as amended [42 U.S.C. 1501 et seq.]. Funds made available for carrying out the functions, powers, and duties of the Secretary of Housing and Urban Development (including appropriations therefor, which are authorized) shall be available, in such amounts as may from year to year be authorized by the Congress, for the administrative expenses of the Secretary of Housing and Urban Development. Notwithstanding any other provisions of law except provisions of law enacted after August 10, 1948 expressly in limitation hereof, the Secretary of Housing and Urban Development, or any State or local public agency administering a low-rent housing project assisted pursuant to the United States Housing Act of 1937 or title II of Public Law 671, Seventy-sixth Congress, approved June 28, 1940, shall continue to have the right to maintain an action or proceeding to recover possession of any housing accommodations operated by it where such action is authorized by the statute or regulations under which such housing accommodations are administered, and, in determining net income for the purposes of tenant eligibility with respect to low-rent housing projects assisted pursuant to said Acts, the Secretary of Housing and Urban Development is authorized, where it finds such action equitable and in the public interest, to exclude amounts or portions thereof paid by the United States Government for disability or death occurring in connection with military service.