I present a broad overview of the current cosmic-ray (CR) transport modeling, and discuss several recent results obtained with the DRAGON code. Several anomalies in the measured CR spectra and gamma-ray data are discussed with particular focus on: the positron excess, the hint of an antiproton excess, the proton and helium spectral breaks, the gamma-ray GeV excess, which may point to either new classes of sources, non-standard propagation models, or new physics. I remark the crucial role of gamma-ray data in this field, as a unique probe of the CR transport properties in different regions in the Galaxy. In the last part I present a recent, detailed analysis of the gamma-ray data in the Galactic ridge in a wide energy range, and discuss whether the H.E.S.S. data can actually point to a PeVatron in the center of the Galaxy.