1. Memory overrun have been fixed.
2. Server failure on assertion has been fixed.


storage/archive/azio.c:
  Fixed bug #31036.
  The ha_archive::rnd_pos function has been modified to take
  into account the result of the azseek function and
  to return HA_ERR_CRASHED_ON_USAGE in case of seek error.
storage/archive/ha_archive.cc:
  Fixed bug #31036.
  1. Memory overrun has been fixed: maximal sizes of azio_stream::inbuf
     and azio_stream::outbuf was mixed.
  2. Zero value of the output parameter of the azread function was
     incorrectly interpreted by the azseek function: after the first
     successful read attempt the execution of the azseek loop was
     interrupted and negative value was returned.
     (See ha_archive::rnd_pos: that negative value was silently ignored,
     and an incomplete data was used, for example, as a size of a packed
     record, and server failed with the assertion:
     "row_len <= record_buffer->length".)
mysql-test/t/archive.test:
  Added test case for bug #31036.
mysql-test/r/archive.result:
  Added test case for bug #31036.