The term "campus novel" became common in the 1950s and generally refers to a novel that takes place primarily in university settings. Campus novel's protagonists are part of a university community—usually professors.
The novel The Paper Men by William Golding is a borderline case. The main character, Wilfred Barclay, is a novelist who does not work on a campus and is not by profession an academic. Much of the plot, however, revolves around the conflict between Barclay and his antagonist, an American academic, Rick L. Tucker, who wants to become Barclay's official biographer.
Although the antagonist in the novel is a professor, the protagonist is not and the story is not really set in an academic environment. It is primarily concerned with the life of a writer with only an indirect connection to academic life. Therefore, I would argue it is not a campus novel.