Spring Boot redirect to current page after successful login

You could use custom AuthenticationSuccessHandler and set useReferer to true.

@Bean
public AuthenticationSuccessHandler successHandler() {
    SimpleUrlAuthenticationSuccessHandler handler = new SimpleUrlAuthenticationSuccessHandler();
    handler.setUseReferer(true);
    return handler;
}

And in your configure method:

http
    .formLogin()
        .loginPage("/login")
        .successHandler(successHandler())
        .permitAll()
        .and()

Just to provide an alternative solution:

formLogin()
    .loginPage("/login")
    .defaultSuccessUrl("/")

defaultSuccessUrl is a shortcut to adding the custom SuccessHandler.