[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#941074: ghostscript: ps2pdf SAFER and transparency interference



Control: tags -1 wontfix

Quoting Markus Demleitner (2019-09-24 11:36:09)
> ps2pdf14 as delivered in buster will only produce PDF transparency 
> when run with -dNOSAFER.  This deviates from previous releases (I'm 
> quite sure about jessie), when transparency was produced without 
> further configuration.  Although I *might* see some relationship to 
> accepting pdfmarks, the connection between SAFER and transparent 
> colours frankly strikes me as just a little non-intuitive (but that 
> may be because I don't know what's going on when producing 
> transparency in PDFs).
> 
> Because of this, I'd suggest that if turning off PDF transparency 
> without -dNOSAFER is intentional, that should be documented in the 
> NEWS, even more so as I couldn't make out that fact in the upstream 
> Use.htm that the current 9.28~~rc1~dfsg-1 NEWS item refers to.  
> Perhaps that particular item could be amended with saying something 
> like "Note that that has some rather unexpected consequences (e.g., 
> PDF transparency is now lost without -dNOSAFER)."

At https://bugs.ghostscript.com/show_bug.cgi?id=701624#c1 upstream 
explains that the operators to apply transparency is non-standard when 
applied to Postscript code.

Upstream has since relaxed to permit these non-standard operators in 
SAFER mode, a change which is (not certain but) likely to appear in next 
upstream release: http://git.ghostscript.com/?p=ghostpdl.git;h=d1eac80

I prefer to not mess with this security-related code to try cherry-pick 
for older relases, and therefore flag this bug as wontfix.

Thanks for reporting,

 - Jonas

-- 
 * Jonas Smedegaard - idealist & Internet-arkitekt
 * Tlf.: +45 40843136  Website: http://dr.jones.dk/

 [x] quote me freely  [ ] ask before reusing  [ ] keep private

Attachment: signature.asc
Description: signature


Reply to: