Function check_list_size 

pub(crate) fn check_list_size(
    remaining: Option<usize>,
    size: usize,
) -> Result<()>

Reject a declared list size that cannot fit the remaining input. Each list element is at least one byte on the wire, so a size past the remaining bytes is a malformed header; bounding it before reserving stops a huge allocation. remaining is None when the protocol is not backed by a finite buffer, in which case there is nothing to check against.