= Solution
The first three terms are the renormalized kinetic, mass, and quartic interaction terms. The remaining three are <counterterms>: $\delta Z$ gives <wave-function renormalization>, $\delta m^2$ renormalizes the mass, and $\delta\lambda$ renormalizes the four-point coupling. With all momenta entering a vertex, the momentum-space <Feynman rules> are
$$
\text{propagator: }\frac{i}{p^2-m^2+i0},
\qquad
\phi^4\text{ vertex: }-i\lambda,
$$
$$
\text{two-point counterterm: }i(\delta Z,p^2-\delta m^2),
\qquad
\text{four-point counterterm: }-i\delta\lambda,
$$
together with momentum conservation at every vertex and an integral $\int d^dp/(2\pi)^d$ for each independent <loop momentum>.
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