On generation of ultra-high-energy cosmic rays in gamma-ray bursts

Solution of the problem of proton acceleration in Gamma-Ray Bursts is suggested. The acceleration occurs in the relativistic shocks via the surfatron mechanism (surfing). It is shown that the proton acceleration up to 1014 – 1017 eV is possible in the case of a spherical shock (fireball); the flat shock accelerates up to 1016 – 1020 eV.