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* Never crash: decompression bombs can't exhaust the renderer's memory The renderer's parser (vendored hayro-syntax) decoded Flate, LZW and RunLength streams with no output limit. A 2 MB page whose content stream inflates to 2 GB, or whose 8 x 8 image does, took `pdfcraft-cli render` and `text` past 3 GB in under a second, and a few more MB of file scale it further. On the desktop that is the first-page render of an emailed PDF, and the allocation-failure abort takes every open document with it. Our own layers already bound single streams (lopdf's load-time decoding at 256 MiB, cos at 1 GiB), so `info` stays at a few MB; the renderer path didn't. Random mutation almost never makes a high-ratio stream, so `cargo xtask fuzz` doesn't find this; found by hand while triaging the fuzz run. Vendored hayro-syntax patch (6): - `decode_limit` gives each filter an output limit, and Flate (both flate2 and the fallback inflater), LZW and RunLength never write past it (the buffer can still grow to under twice it): `MAX_DECODED_STREAM`, 256 MiB, lopdf's figure; or, for the last filter of an image whose size, bits per component and components are known, twice its pixel bytes (a PNG predictor tag byte per byte at most), capped at 1 GiB. Earlier filters in a chain produce compressed data and get the general limit. - `Stream::decoded_within(max)` for callers that budget. - A page's `/Contents` array shares one `MAX_DECODED_STREAM` (naming one bomb twenty times decoded 5 GB), reserving exactly what it appends. Vendored hayro-interpret patch (18): - The content a page holds at once (its contents, and the forms, tiling patterns and Type 3 glyph procedures being painted) stays within `MAX_PAGE_CONTENT`, 512 MiB, reset per page like the existing paint budget. Forms nest fifty deep and each level kept its content while the next ran: a form painting itself around a 256 MiB stream would have held over 12 GB. Each level gives its bytes back when it is dropped, so content painted again and again keeps drawing, and a stream without filters (borrowed from the file) costs nothing. - Type 0 sampled functions read every sample into a 4-byte value and then a table entry: 256 MiB of 1-bit samples asked for over 8 GB. They now take at most 2^21 table points and 2^23 values (the largest real tables, DeviceN tint transforms such as 33^4 points x 3 outputs, are 1.2 million and 3.6 million), counted with checked arithmetic, and read no further than `/Size` asks. `/Size 0` no longer underflows building the default `/Encode`. Three rounds of independent review found the aggregate cases, buffer doubling past the limit, a chain/predictor shape the first image limit would have truncated, the Type 0 amplifier, and a first, cumulative budget that would have dropped legitimately repeated content, and a first Type 0 cap low enough to refuse real tint transforms; all fixed here. Measured in a release build (render; OS peak commit): - content stream inflating to 2 GB: 389 MB, 0.3 s - 8 x 8 image inflating to 2 GB: 4 MB, 0.2 s - /Contents naming it twenty times: 516 MB, 0.3 s - a form painting itself around it: 644 MB, 0.4 s Synthetic regression tests in render (flate2 is a new dev-dependency there, already in the workspace): - `decompression_bombs_stop_at_the_stream_limit`: 288 MiB bombs through flate2, the fallback inflater (a stored block with a wrong length check, which flate2 refuses and the fallback accepts), LZW and RunLength each decode exactly 256 MiB, and at most 128 bytes as an 8 x 8 image. - `page_contents_and_nested_forms_share_one_budget`: three /Contents references decode one stream's worth; a self-painting form finishes. - `content_painted_again_and_again_keeps_drawing`: a 2 MiB form painted 300 times draws the 300th time. - `sampled_functions_with_billions_of_samples_are_refused`. Ten mutations each turn them red: no limit at all; no limit in flate2, the fallback, LZW, RunLength or for images; an unshared /Contents limit; no page budget; no refund on drop; no Type 0 sample cap. (Taking a form out of the budget no longer compiles: its content is the budget guard.) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * M2: normalize JPEG2000 samples without overflowing Use bounded integer sample scaling for 1-32-bit JPX images and reject empty dimensions before chunking. Cover public decoding and continued page rendering with synthetic regressions. Co-Authored-By: OpenAI Codex <codex@openai.com> * Never crash: decompression cut at its limit is logged, not silent; vendor README renumbered after #575 --------- Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com> Co-authored-by: Streetblock <github@streetblock.de> Co-authored-by: OpenAI Codex <codex@openai.com> Co-authored-by: Brandon Thomas <echelon@gmail.com>