  We introduce and analyse an efficient decoder for the quantum Tanner codes of
that can correct adversarial errors of linear weight. Previous decoders for
quantum low-density parity-check codes could only handle adversarial errors of
weight $O(\sqrt{n \log n})$. We also work on the link between quantum Tanner
codes and the Lifted Product codes of Panteleev and Kalachev, and show that our
decoder can be adapted to the latter. The decoding algorithm alternates between
sequential and parallel procedures and converges in linear time.
