I'm analyzing a protocol that, during one of the steps, sends a blinded secret. Let's denote the secret $x \in \mathbb Z_p^*$ (for $p$ prime) and the blinded secret $y$, so that $y = r\cdot x \bmod p$, where $r$ is a blinding factor randomly sampled from $\mathbb Z_p^*$. We can assume that the blinding factors won't repeat.
Several runs of the protocol would produce several $y_i$ values, with the same fixed secret $x$:
$$y_1 = r_1 \cdot x \bmod p$$ $$y_2 = r_2 \cdot x \bmod p$$ $$...$$ $$y_n = r_n \cdot x \bmod p$$
Knowing only the $y_i$ values, what would be the best algorithm to retrieve $x$?