A text field with the Password flag kept its typed value in /V, so Save, a full
rewrite, Reduce File Size and the recovery snapshots all wrote it in plain text.
ISO 32000-2 §12.7.5.3, Table 231 (note to the Password flag): PDF processors
should never store the value in the PDF file. Each of those paths now writes a
copy without the values; the open document keeps them in memory, and the masked
appearance is kept.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
fix(xfdf, sign, preflight, engine, forms, measure, annot): bound repeated work in form exchange, preflight and export, and check what imports and time stamps claim
Extraction walked the name tree again with a fresh key budget, so keys
the listing had left out could fill it and a listed embedded file came
back as not found. The lookup compares each key with the one wanted and
keeps none, so it needs no budget; a key object or /Names array that
several places reference is converted once.
A kept web address or attachment text spent only its converted length,
so a long raw value that trimmed short was converted in full for every
entry sharing it. A kept conversion now spends the longer of its raw
and converted lengths.
The embedded-files name tree copied every key, and an attachment
without a file name copied its key again as the name, so many entries
sharing one long key string multiplied it. Keys, and a key kept again
as the name, now spend the 16 MiB link and attachment text budget; an
embedded file whose key does not fit is not listed.
An annotation attachment's /Contents was read and charged to the text
budget before the file specification's /UF or /F, which then named the
attachment, so the discarded text could leave a later web address
unlisted. /Contents is now read only when neither name is there.
A web address or attachment text that converted to more than the budget
left spent nothing, so every link or attachment sharing it converted it
again. A conversion that comes out too long now spends the raw length,
and so does attachment text that trims to nothing.
The fixture's image stream held six bytes under /Length 4, and the test
only checked that the picture was missing at a zero budget, which a
picture that could not be prepared also passes. The stream is four
bytes, and the picture is first shown to export at a 1 MiB budget.
The link and attachment listings copied a link's web address and an
attachment's name and description for every annotation or name-tree
entry, so many entries sharing one long string multiplied it in
memory. Together they keep at most 16 MiB of that text, and a string
past what is left is not converted. A link past it lists as a URI
action without its address, an attachment under its generic name
without a description.
The annotation listing skipped a repeated /Annots entry by its raw
reference, so an indirect object holding only a reference to a link
listed that link a second time. Entries and page arrays are now told
apart by the object their reference chain ends at. The lopdf reader
reported the first object of a chain, because lopdf's get_object
already follows it; it now reports the last, as the lazy reader does.
A /Kids array listing one widget many times, or shared by several fields,
built a Widget for every listing, so a small file expanded into fields times
listings widgets. A widget now belongs to the first field that lists it, and a
page widget already owned is not adopted again.
The tests each branch appends to the audit, edit and organize test files are
kept side by side; prune.rs merges cleanly, with the form memo on top of the
budgeted page content.
The JPEG decoder re-sorts and rescans every pending Extended XMP chunk after
each marker, so a file of many small chunks cost time quadratic in their
number before any pixel limit applied. Turning a photo upright now counts
the chunks first and leaves a JPEG with more than 1024 as it is.
A one-pixel GIF on a huge logical screen decodes to a canvas that size,
which the conversion then copied before splitting it into colour and alpha,
so a few bytes could hold over a gigabyte. Screens past 16 Mpx are refused
before decoding, and the decoded canvas is converted without a copy.
A TIFF's pages were each capped at 2 GiB but all kept in memory until
embedded, so many small directories sharing one compressed strip could ask
for many times that; embedding one image also decoded every page. The pages
of one TIFF are now refused past 4 GiB together, and image_xobject reads
only the first page.
The redaction audit read each page's text through text_lines, which walked
the whole page tree again for every page (quadratic in the page count) and
let /ActualText replace the glyphs, so an empty or substitute ActualText hid
covered text from the audit. Edit gains glyph_text_lines, which reads the
page dictionary it is given and ignores ActualText; the audit uses it.
Text extraction copies a ToUnicode destination for every glyph showing its
code, and the page's total text was not bounded, so a small page could expand
into gigabytes. One page's extraction (its forms included) stops with an error
past 16 MiB of text.
Past the marked-content depth budget the number of open sequences is unknown,
and the mark on top was appended with none of them closed, so the page's own
optional-content scopes (possibly hidden) could hide a redaction box, a
header or a watermark. Placing on top of such a page is now refused before
anything changes; behind it is still possible.
Removing flattened widgets from the field tree recursed into every /Kids
entry with only a depth limit, so a node listing its child twice per level
(or itself) made the walk exponential. Each node's answer is now remembered;
a node met again while it is still being visited survives, as it did when
the depth limit stopped a cycle.
Writing an added text item re-wrapped the whole text inside the loop over its
lines to learn the line count, so multiline text cost time and temporary
memory quadratic in its length. The wrapped lines are computed once.
Each candidate attribute match searched the whole packet before it for the
last < and >, so a long text node repeating the attribute name cost time
quadratic in the packet size (up to the 16 MiB decode cap). The scan now
keeps the last < and > as it moves forward.
