mDNS crash

[blampe]

Describe the bug

The library seems to crash on certain mDNS datagrams.

Error log

[5/27/2025, 3:06:23 AM] [Apple TV Enhanced] [E] Platform: Error: Unable to execute request G: exception during data handling
Traceback (most recent call last):
  File "/var/lib/homebridge/appletv-enhanced/.venv/lib/python3.12/site-packages/pyatv/core/mdns.py", line 306, in datagram_received
    delegate.datagram_received(data, addr)
  File "/var/lib/homebridge/appletv-enhanced/.venv/lib/python3.12/site-packages/pyatv/core/mdns.py", line 432, in datagram_received
    decoded_msg = DnsMessage().unpack(data)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/homebridge/appletv-enhanced/.venv/lib/python3.12/site-packages/pyatv/support/dns.py", line 377, in unpack
    header = DnsHeader.unpack_read(buffer)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/homebridge/appletv-enhanced/.venv/lib/python3.12/site-packages/pyatv/support/dns.py", line 298, in unpack_read
    return cls._make(unpack_stream(">6H", buffer))
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/homebridge/appletv-enhanced/.venv/lib/python3.12/site-packages/pyatv/support/dns.py", line 25, in unpack_stream
    return struct.unpack(fmt, buffer.read(size))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
struct.error: unpack requires a buffer of 12 bytes

How to reproduce the bug?

I'm not sure which DNS entry this is. I've enabled verbose logging and hopefully it will include some more information.

What is expected behavior?

Shouldn't crash.

Operating System

Linux

Python

3.9

pyatv

0.16.0

Device

ATV HD 4th gen tvOS 18

Additional context

Using as part of homebridge-appletv-enhanced.