OpenSystemsDevelopment / qpdf

Throw damagedFile if max_warnings is exceeded. Change qpdf_fuzzer warnings limit to
limit to 500.

Tighten page tree checks

Add further sanity checks to QPDF::reconstruct_xref

Run getAllPages as sanity check and throw an exception if too many
warnings are generated or no pages are found.

Add further sanity check to QPDF::reconstruct_xref

Try a  limit of 50MB. For very large limits processing time before
damage is encountered may exceed oss-fuzz limits.
Add further test cases.

If reconstruct_xref generates more than 1000 warnings give up because the
file is so severely damaged that there is very little point continuing.

Add extra sanity check on pages tree

Reject non-dictionary Page and Pages objects.

Also add additional qpdf_fuzzer test cases.

Add additional xref reconstruction sanity checks and fuzz test cases

If throw_on_corrupt is set, use a custom implementation of libjeg's
emit_message procedure to throw an exception when the first corrupt data
warning is encountered.

Add test case for oss-fuzz 15471 and 69977a

Check that xref table is not empty after recovery. Empty xref tables
disable other sanity checks.

Fix Pl_DCT memory limit

Add qpdf_fuzzer test case

In QPDF::processXRefIndex check number of objects in subsection is > 0

Fixes oss-fuzz 70055

Alternative clean dct fuzz changes

Previous test case was lost in #1221. Test file was created from
object-stream.pdf by adding a reference to itself into object stream 1 0.

As a rule, we should avoid conditional compilation is it always causes
code paths that are sometimes not even seen lexically by the compiler.
Also, we want the actual code being fuzzed to be as close as possible
to the real code. Conditional compilation is suitable to handle
underlying system differences.

Instead, favor configuration using callbacks or other methods that can
be triggered in the places where they need to be exercised.

Add further sanity and loop detection checks

Invalid entries are created when objects in the stream do not have
an existing xref entry.

Ensure objects with impossibly large ids are ignored.

Add extra fuzz test case and amend memory limit for Pl_DCT.

Refine #1225

In QPDFOutlineObjectHelper detect loops in direct children

Also, add diagnostic messages in qpdf_fuzzer and additional fuzz test case.