Attorney and freelance writer Dina M. Di Maio tells you about using song lyrics in your book:
I want to quote lyrics from a popular song in my novel? Must I get permission to do so?
Published works, including song lyrics, copyrighted before 1923 are in the public domain, which means they are no longer copyright-protected and you may use them freely in your work without permission.
However, most writers want to use contemporary song lyrics in their work. For these songs, you must get permission from the copyright owner.
. . . .
But what if I only want to use a few lines?
A song or poem warrants the same protection as a novel. Since a song or poem is much shorter, taking a few lines from a song could be like using 60% of the work. Isn’t it fair use just to quote a few lines from the song? A popular misconception of fair use is that it means it is fair for you to use copyrighted material because you are only using a little bit of it.
Link to the rest at New York Book Woman
Passive Guy will add that you’ll run into similar issues using poems that are still under copyright. Many are so short that even a couple of lines will be the equivalent of someone copying 25 pages from your novel.