1529502 - Certain characters in pdfs do not display correctly

Status: RESOLVED FIXED

(Firefox :: PDF Viewer, defect, P1)

Description

[Jonas Jenwald [:Snuffleupagus]]

See https://bugzilla.mozilla.org/show_bug.cgi?id=1524888#c14, and for what it's worth I don't agree with closing than one when the underlying font conversion bug still isn't fixed.

---

+++ This bug was initially created as a clone of Bug #1524888 +++

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:65.0) Gecko/20100101 Firefox/65.0

Steps to reproduce:

1. Go to this pdf file: https://1password.com/files/1Password%20for%20Teams%20White%20Paper.pdf

2. The first occurence of this issue appears on page 10.

Actual results:

The character is displayed incorrectly. See the attached screenshot.

Expected results:

The characters "18000" should be displayed.

Comment 1

[Brendan Dahl [:bdahl]]

Notes for when I (or someone else) get time to look into this:

The font "VENLVK+FiraMath-Regular" fail to run through the open type sanitizer:
ERROR at ../src/cff_type2_charstring.cc:388 (ExecuteType2CharStringOperator)
ERROR at ../src/cff_type2_charstring.cc:793 (ExecuteType2CharString)
ERROR at ../src/cff_type2_charstring.cc:901 (ValidateType2CharStringIndex)
ERROR: CFF : Failed validating charstring set 0
ERROR at ../src/ots.cc:698 (ProcessGeneric)
ERROR: CFF : Failed to parse table
Failed to sanitize file!

The charstring 24 (or 25 in pdf.js) is the glyph that fails because it starts with:
"71 cntrmask" and appears to have no stem hints before that.

From the spec:
"The hint operators cntrmask and/or hintmask must not occur if the charstring has no stem hints."

Comment 2

[Brendan Dahl [:bdahl]]

Attachment: bug152488_reduced.pdf

Reduced test case.

Comment 3

[Brendan Dahl [:bdahl]]

Removing the regression flag, since we have the work around and don't need to track this across releases.

Comment 4

[Kenan]

Works for me / it was fixed 2019-02-13 to 2019-02-14 (mozregression)

The test case looks identically on FF (nightly) and Adobe Acrobat
FF with Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:97.0) Gecko/20100101 Firefox/97.0

but console shows:
Warning: Failed to load font 'g_d0_f2': 'SyntaxError: An invalid or illegal string was specified'. pdf.js:925:13
downloadable font: CFF : Failed validating CharStrings INDEX (font-family: "g_d0_f2" style:normal weight:400 stretch:100 src index:0) source: (invalid URI)
downloadable font: CFF : Failed to parse table (font-family: "g_d0_f2" style:normal weight:400 stretch:100 src index:0) source: (invalid URI)
downloadable font: rejected by sanitizer (font-family: "g_d0_f2" style:normal weight:400 stretch:100 src index:0) source: (invalid URI)
downloadable font: font load failed (font-family: "g_d0_f2" style:normal weight:400 stretch:100 src index:0) source: (invalid URI)

mozregression:
app_name: firefox
build_date: 2019-02-15
build_url: https://archive.mozilla.org/pub/firefox/nightly/2019/02/2019-02-15-18-40-35-mozilla-central/firefox-67.0a1.en-US.win64.zip
changeset: 8961019ee4c6fe27e6319d9cf9ea6867b4f3c7bb
pushlog_url: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=08f794a4928eed47fe7a0f9a0c818b8f2a7fa11a&tochange=8961019ee4c6fe27e6319d9cf9ea6867b4f3c7bb
repo_name: mozilla-central
repo_url: https://hg.mozilla.org/mozilla-central

Comment 5

[Ryan VanderMeulen [:RyanVM]]

Bug 1527714 is in that range, and one change looks relevant:
#10539 [api-minor] Fallback to the built-in font renderer when font loading fails

Comment 6

[Jonas Jenwald [:Snuffleupagus]]

(In reply to Kenan from comment #4)

but console shows:
Warning: Failed to load font 'g_d0_f2': 'SyntaxError: An invalid or illegal string was specified'. pdf.js:925:13
downloadable font: CFF : Failed validating CharStrings INDEX (font-family: "g_d0_f2" style:normal weight:400 stretch:100 src index:0) source: (invalid URI)
downloadable font: CFF : Failed to parse table (font-family: "g_d0_f2" style:normal weight:400 stretch:100 src index:0) source: (invalid URI)
downloadable font: rejected by sanitizer (font-family: "g_d0_f2" style:normal weight:400 stretch:100 src index:0) source: (invalid URI)
downloadable font: font load failed (font-family: "g_d0_f2" style:normal weight:400 stretch:100 src index:0) source: (invalid URI)

This bug was opened specifically to fix the underlying font conversion bug, which is still present (according to the quote above).

Yes, a work-around exists; but it'd still be a good idea to fix the actual bug here such that the font isn't rejected by OTS.

Comment 7

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee is inactive on Bugzilla, so the assignee is being reset.

Comment 8

[BMO Github Automation]

Attachment: [mozilla/pdf.js] [OTS] Remove cntrmask instruction with no stem in charstring (bug 1529502) (#16483)