From 0661bf23a5be32973682e17afed4a2f23a8214ba Mon Sep 17 00:00:00 2001 From: Chris Liddell Date: Sat, 29 Sep 2018 15:34:55 +0100 Subject: [PATCH 2/5] Bug 699816: Improve hiding of security critical custom operators Make procedures that use .forceput/.forcedef/.forceundef into operators. The result of this is that errors get reported against the "top" operator, rather than the "called" operator within the procedure. For example: /myproc { myop } bind def If 'myop' throws an error, the error handler will be passed the 'myop' operator. Promoting 'myproc' to a operator means the error handler will be passed 'myproc'. CVE: CVE-2018-17961 Upstream-Status: Backport [git://git.ghostscript.com/ghostpdl.git] Signed-off-by: Hongxu Jia --- Resource/Init/gs_diskn.ps | 2 +- Resource/Init/gs_dps.ps | 2 +- Resource/Init/gs_fntem.ps | 2 +- Resource/Init/gs_fonts.ps | 10 +++++----- Resource/Init/gs_lev2.ps | 13 +++++++++---- Resource/Init/gs_pdfwr.ps | 2 +- Resource/Init/gs_setpd.ps | 25 +++++++++++++++++-------- Resource/Init/gs_typ32.ps | 14 +++++++++----- Resource/Init/gs_type1.ps | 2 +- Resource/Init/pdf_base.ps | 2 +- Resource/Init/pdf_draw.ps | 10 +++++----- Resource/Init/pdf_font.ps | 8 ++++---- Resource/Init/pdf_main.ps | 4 ++-- Resource/Init/pdf_ops.ps | 8 ++++---- 14 files changed, 61 insertions(+), 43 deletions(-) diff --git a/Resource/Init/gs_diskn.ps b/Resource/Init/gs_diskn.ps index 5540715..26ec0b5 100644 --- a/Resource/Init/gs_diskn.ps +++ b/Resource/Init/gs_diskn.ps @@ -53,7 +53,7 @@ systemdict begin exch .setglobal } if -} .bind executeonly def % must be bound and hidden for .forceput +} .bind executeonly odef % must be bound and hidden for .forceput % Modify .putdevparams to force regeneration of .searchabledevs list /.putdevparams { diff --git a/Resource/Init/gs_dps.ps b/Resource/Init/gs_dps.ps index cad7056..daf7b0f 100644 --- a/Resource/Init/gs_dps.ps +++ b/Resource/Init/gs_dps.ps @@ -70,7 +70,7 @@ % Save a copy of the initial gstate. //systemdict /savedinitialgstate gstate readonly .forceput .setglobal -} .bind executeonly def % must be bound and hidden for .forceput +} .bind executeonly odef % must be bound and hidden for .forceput % Initialize local dictionaries and gstate when creating a new context. % Note that until this completes, we are in the anomalous situation of diff --git a/Resource/Init/gs_fntem.ps b/Resource/Init/gs_fntem.ps index 3ceee18..c1f7651 100644 --- a/Resource/Init/gs_fntem.ps +++ b/Resource/Init/gs_fntem.ps @@ -408,7 +408,7 @@ currentdict end def exit } loop exch setglobal -} .bind executeonly def % must be bound and hidden for .forceput +} .bind executeonly odef % must be bound and hidden for .forceput currentdict end /ProcSet defineresource pop diff --git a/Resource/Init/gs_fonts.ps b/Resource/Init/gs_fonts.ps index 45b6613..89c3ab7 100644 --- a/Resource/Init/gs_fonts.ps +++ b/Resource/Init/gs_fonts.ps @@ -377,8 +377,8 @@ FONTPATH length 0 eq { (%END FONTPATH) .skipeof } if } {pop} ifelse -} .bind executeonly def -systemdict /NONATIVEFONTMAP known //.setnativefontmapbuilt exec +} .bind executeonly odef +systemdict /NONATIVEFONTMAP known .setnativefontmapbuilt /.buildnativefontmap { % - .buildnativefontmap systemdict /.nativefontmapbuilt .knownget not { //false} if @@ -419,7 +419,7 @@ systemdict /NONATIVEFONTMAP known //.setnativefontmapbuilt exec } forall } if % record that we've been run - //true //.setnativefontmapbuilt exec + //true .setnativefontmapbuilt } ifelse } bind def currentdict /.setnativefontmapbuilt .forceundef @@ -1103,7 +1103,7 @@ $error /SubstituteFont { } put % Check to make sure the font was actually loaded. dup 3 index .fontknownget - { dup /PathLoad 4 index //.putgstringcopy exec + { dup /PathLoad 4 index .putgstringcopy 4 1 roll pop pop pop //true exit } if @@ -1115,7 +1115,7 @@ $error /SubstituteFont { } put { % Stack: origfontname fontdirectory path filefontname 2 index 1 index .fontknownget { % Yes. Stack: origfontname fontdirectory path filefontname fontdict - dup 4 -1 roll /PathLoad exch //.putgstringcopy exec + dup 4 -1 roll /PathLoad exch .putgstringcopy % Stack: origfontname fontdirectory filefontname fontdict 3 -1 roll pop % Stack: origfontname filefontname fontdict diff --git a/Resource/Init/gs_lev2.ps b/Resource/Init/gs_lev2.ps index eee0b9f..a8ed892 100644 --- a/Resource/Init/gs_lev2.ps +++ b/Resource/Init/gs_lev2.ps @@ -163,10 +163,11 @@ end % Set them again to the new values. From here on, we are safe, % since a context switch will consult userparams. .setuserparams -} .bind executeonly def % must be bound and hidden for .forceput +} .bind executeonly odef % must be bound and hidden for .forceput /setuserparams { % setuserparams - - .setuserparams2 + {.setuserparams2} stopped + {/setuserparams load $error /errorname get signalerror} if } .bind odef % Initialize user parameters managed here. /JobName () .definepsuserparam @@ -415,7 +416,9 @@ psuserparams /ProcessDSCComment {.checkprocesscomment} put % VMReclaim and VMThreshold are user parameters. /setvmthreshold { % setvmthreshold - - mark /VMThreshold 2 .argindex .dicttomark .setuserparams2 pop + mark /VMThreshold 2 .argindex .dicttomark {.setuserparams2} stopped + {pop /setvmthreshold load $error /errorname get signalerror} + {pop} ifelse } odef /vmreclaim { % vmreclaim - dup 0 gt { @@ -427,7 +430,9 @@ psuserparams /ProcessDSCComment {.checkprocesscomment} put ifelse } { % VMReclaim userparam controls enable/disable GC - mark /VMReclaim 2 index .dicttomark .setuserparams2 pop + mark /VMReclaim 2 index .dicttomark {.setuserparams2} stopped + {pop /vmreclaim load $error /errorname get signalerror} + {pop} ifelse } ifelse } odef -1 setvmthreshold diff --git a/Resource/Init/gs_pdfwr.ps b/Resource/Init/gs_pdfwr.ps index fb1c419..58e75d3 100644 --- a/Resource/Init/gs_pdfwr.ps +++ b/Resource/Init/gs_pdfwr.ps @@ -660,7 +660,7 @@ currentdict /.pdfmarkparams .undef { pop } ifelse -} .bind executeonly def % must be bound and hidden for .forceput +} .bind executeonly odef % must be bound and hidden for .forceput % Use the DSC processing hook to pass DSC comments to the driver. % We use a pseudo-parameter named DSC whose value is an array: diff --git a/Resource/Init/gs_setpd.ps b/Resource/Init/gs_setpd.ps index 8fa7c51..afb4ffa 100644 --- a/Resource/Init/gs_setpd.ps +++ b/Resource/Init/gs_setpd.ps @@ -608,6 +608,20 @@ NOMEDIAATTRS { % in the dictionary with the policy value, % and we replace the key in the dictionary with its prior value % (or remove it if it had no prior value). + +% Making this an operator means we can properly hide +% the contents - specifically .forceput +/1Policy +{ + % Roll back the failed request to its previous status. + SETPDDEBUG { (Rolling back.) = pstack flush } if + 3 index 2 index 3 -1 roll .forceput + 4 index 1 index .knownget + { 4 index 3 1 roll .forceput } + { 3 index exch .undef } + ifelse +} bind executeonly odef + /.policyprocs mark % These procedures are called with the following on the stack: % @@ -631,14 +645,7 @@ NOMEDIAATTRS { /setpagedevice .systemvar /configurationerror signalerror } ifelse } bind - 1 { % Roll back the failed request to its previous status. -SETPDDEBUG { (Rolling back.) = pstack flush } if - 3 index 2 index 3 -1 roll .forceput - 4 index 1 index .knownget - { 4 index 3 1 roll .forceput } - { 3 index exch .undef } - ifelse - } .bind executeonly % must be bound and hidden for .forceput + 1 /1Policy load 7 { % For PageSize only, just impose the request. 1 index /PageSize eq { pop pop 1 index /PageSize 7 put } @@ -646,6 +653,8 @@ SETPDDEBUG { (Rolling back.) = pstack flush } if ifelse } bind .dicttomark readonly def +currentdict /1Policy undef + /.applypolicies % .applypolicies % { 1 index /Policies get 1 index diff --git a/Resource/Init/gs_typ32.ps b/Resource/Init/gs_typ32.ps index b6600b0..9150f71 100644 --- a/Resource/Init/gs_typ32.ps +++ b/Resource/Init/gs_typ32.ps @@ -79,15 +79,19 @@ systemdict /.removeglyphs .undef .dicttomark /ProcSet defineresource pop /.cidfonttypes where { pop } { /.cidfonttypes 6 dict def } ifelse -.cidfonttypes begin - -4 % CIDFontType 4 = FontType 32 -{ dup /FontType 32 .forceput +/CIDFontType4 +{ + dup /FontType 32 .forceput dup /CharStrings 20 dict .forceput 1 index exch .buildfont32 exch pop -} .bind executeonly def % must be bound and hidden for .forceput +} .bind executeonly odef +.cidfonttypes begin + + +4 /CIDFontType4 load def % CIDFontType 4 = FontType 32 end % .cidfonttypes +currentdict /CIDFontType4 .forceundef % Define the BuildGlyph procedure. % Since Type 32 fonts are indexed by CID, there is no BuildChar procedure. diff --git a/Resource/Init/gs_type1.ps b/Resource/Init/gs_type1.ps index efdae48..2935d9c 100644 --- a/Resource/Init/gs_type1.ps +++ b/Resource/Init/gs_type1.ps @@ -283,7 +283,7 @@ currentdict /closesourcedict .undef } if 2 copy /WeightVector exch .forceput .setweightvector -} .bind executeonly def +} .bind executeonly odef end % Register the font types for definefont. diff --git a/Resource/Init/pdf_base.ps b/Resource/Init/pdf_base.ps index a82a2a3..7ccd4cd 100644 --- a/Resource/Init/pdf_base.ps +++ b/Resource/Init/pdf_base.ps @@ -218,7 +218,7 @@ currentdict /num-chars-dict .undef } ifelse } ifelse } ifelse -} bind executeonly def +} bind executeonly odef /PDFScanRules_true << /PDFScanRules //true >> def /PDFScanRules_null << /PDFScanRules //null >> def /.pdfrun { % .pdfrun - diff --git a/Resource/Init/pdf_draw.ps b/Resource/Init/pdf_draw.ps index d1b6ac9..c239daf 100644 --- a/Resource/Init/pdf_draw.ps +++ b/Resource/Init/pdf_draw.ps @@ -1158,7 +1158,7 @@ currentdict end readonly def Q PDFDEBUG { pdfdict /PDFSTEPcount .knownget { 1 le } { //true } ifelse { (%End PaintProc) print dup === flush } if } if PDFfile exch setfileposition -} bind executeonly def +} bind executeonly odef /.pdfpaintproc { %% Get the /m from pdfopdict (must be present) @@ -1189,7 +1189,7 @@ currentdict end readonly def { switch_to_text_marking_ops } if -}bind executeonly def +}bind executeonly odef /resolvepattern { % resolvepattern % Don't do the resolvestream now: just capture the data @@ -2353,7 +2353,7 @@ currentdict /last-ditch-bpc-csp undef }{ pdfdict /AppearanceNumber 0 .forceput } ifelse -}bind executeonly def +}bind executeonly odef /MakeAppearanceName { pdfdict /AppearanceNumber get @@ -2382,7 +2382,7 @@ currentdict /last-ditch-bpc-csp undef DoForm pdfdict /.PreservePDFForm 3 -1 roll .forceput grestore -} bind executeonly def +} bind executeonly odef /DoForm { %% save the current value, if its true we will set it to false later, in order @@ -2541,7 +2541,7 @@ currentdict /last-ditch-bpc-csp undef end } if pdfdict /.PreservePDFForm 3 -1 roll .forceput -} bind executeonly def +} bind executeonly odef /_dops_save 1 array def diff --git a/Resource/Init/pdf_font.ps b/Resource/Init/pdf_font.ps index feaf0d0..535b14a 100644 --- a/Resource/Init/pdf_font.ps +++ b/Resource/Init/pdf_font.ps @@ -718,7 +718,7 @@ currentdict end readonly def {pop pop pop} ifelse -} bind executeonly def +} bind executeonly odef currentdict /.DoToUnicode? .forceundef @@ -1241,7 +1241,7 @@ currentdict /eexec_pdf_param_dict .undef } bdef dup currentdict Encoding .processToUnicode currentdict end .completefont exch pop -} bind executeonly def +} bind executeonly odef /.adjustcharwidth { % .adjustcharwidth % Enforce the metrics, in glyph space, to the values found in the PDF Font object % - force wy == 0 (assumed, and not stored in the PDF font) @@ -2026,7 +2026,7 @@ currentdict /CMap_read_dict undef } if /findresource cvx /undefined signalerror } loop -} bind executeonly def +} bind executeonly odef /buildCIDType0 { % buildCIDType0 dup /BaseFont get findCIDFont exch pop @@ -2211,7 +2211,7 @@ currentdict /CMap_read_dict undef /Type0 //buildType0 /Type1 //buildType1 /MMType1 //buildType1 - /Type3 //buildType3 + /Type3 /buildType3 load /TrueType //buildTrueType /CIDFontType0 //buildCIDType0 /CIDFontType2 //buildCIDType2 diff --git a/Resource/Init/pdf_main.ps b/Resource/Init/pdf_main.ps index 09f8735..c823e69 100644 --- a/Resource/Init/pdf_main.ps +++ b/Resource/Init/pdf_main.ps @@ -660,7 +660,7 @@ currentdict /runpdfstring .undef } forall pop } ifelse -} bind executeonly def +} bind executeonly odef currentdict /pdf_collection_files .undef @@ -2715,7 +2715,7 @@ currentdict /PDF2PS_matrix_key undef .setglobal /RepairedAnError exch def /Repaired exch def -} bind executeonly def +} bind executeonly odef % Display the contents of a page (including annotations). /showpagecontents { % showpagecontents - diff --git a/Resource/Init/pdf_ops.ps b/Resource/Init/pdf_ops.ps index c45fc51..8672d61 100644 --- a/Resource/Init/pdf_ops.ps +++ b/Resource/Init/pdf_ops.ps @@ -193,7 +193,7 @@ currentdict /gput_always_allow .undef pdfformaterror } ifelse } if -} bind executeonly def +} bind executeonly odef % Save PDF gstate /qstate { % - qstate @@ -451,7 +451,7 @@ currentdict /gput_always_allow .undef %% a gsave, so we haven't copied it to /self, if we don't do that here %% then transparent annotations cause an invalid access error. currentdict //nodict eq {/self dup load end 5 dict begin def} if -} bind executeonly def +} bind executeonly odef /AIS { .setalphaisshape } bind executeonly def /BM { /.setblendmode where { @@ -1077,7 +1077,7 @@ end readonly def pdfopdict /v {inside_text_v} bind .forceput pdfopdict /y {inside_text_y} bind .forceput pdfopdict /re {inside_text_re} bind .forceput -} bind executeonly def +} bind executeonly odef /switch_to_normal_marking_ops { pdfopdict /m {normal_m} bind .forceput @@ -1086,7 +1086,7 @@ end readonly def pdfopdict /v {normal_v} bind .forceput pdfopdict /y {normal_y} bind .forceput pdfopdict /re {normal_re} bind .forceput -} bind executeonly def +} bind executeonly odef /BT { currentdict /TextSaveMatrix known { -- 2.7.4