RSA Crypto reconstructing m by knowing (m mod p)

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Let $c = m^e \mod N$ be a RSA-ciphertext with $N = pq$.

Let $m_p = m \mod p$ be known

Knowing this, how can i reconstruct $m$ in polynomial time with respect to $log N$ and $log e$ ?

I suspect it might have to do with chinese remainder theorem, but i am not entirely sure. I know we need to find m, such that

$gcd(m - m_p, N) = p$, but i dont quite see, how we can do that in polynomial time