Affected versions of this crate passes an uninitialized buffer to a user-provided
Read implementations can read from the uninitialized buffer (memory exposure)
and also can return incorrect number of bytes written to the buffer.
Reading from uninitialized memory produces undefined values that can quickly invoke
Note: there is only UB in the case where a user provides a struct whose
implementation inspects the buffer passed to
read_exact before writing to it.
This is an unidiomatic (albeit possible)
See https://github.com/MaterializeInc/materialize/issues/8669 for details.