The imaging build decodes the full pixel buffer from the header-declared
dimensions before the existing MaxInputWidth/MaxInputHeight guard runs, so a
tiny crafted file whose header declares huge dimensions forces a multi-GB
allocation and can OOM the worker. Read the header with DecodeConfig and reject
oversized sources before the decode allocates, in both the imaging and vips
builds, and thread the limit through the audio cover-art and geogebra decoders
that decode a second attacker-controlled image.
