kicad-developers team mailing list archive

[Andrew Zonenberg <azonenberg@xxxxxxxxxxxxxxx>]

I was investigating some memory corruption segfaults with Valgrind and
found that the netlist-import code in pcbnew is calling
wxString::Printf() with a char* using the %s format specifier.

While this may look right, the _() macro (through many levels of
indirection) converts %s to %ls, which expects a wide character string.

The end result is that wcslen() gets called with a char* string, fails
to stop at the 1-byte null character, and keeps on reading off the end
causing garbage to be strewn through memory and sometimes crash pcbnew.
This can be fixed by forcibly converting the incoming UTF-8 string to
wchar_t* before passing it to wxString::Printf().

The attached patch was tested on wx 2.8 on Debian 7 64-bit. I'm not sure
if it breaks anything on Windows or wx 3.0 so please test carefully :)

-- 
Andrew Zonenberg
PhD student, security group
Computer Science Department
Rensselaer Polytechnic Institute
http://colossus.cs.rpi.edu/~azonenberg/

=== modified file 'pcbnew/netlist.cpp'
--- pcbnew/netlist.cpp	2014-06-05 07:54:47 +0000
+++ pcbnew/netlist.cpp	2014-08-13 06:18:06 +0000
@@ -242,8 +242,8 @@
             {
                 msg.Printf( _( "* Warning: component '%s' has footprint '%s' and should be '%s'\n" ),
                             GetChars( component->GetReference() ),
-                            fpOnBoard->GetFPID().GetFootprintName().c_str(),
-                            component->GetFPID().GetFootprintName().c_str() );
+                            wxString( fpOnBoard->GetFPID().GetFootprintName() ).wc_str(),
+                            wxString( component->GetFPID().GetFootprintName() ).wc_str() );
                 aReporter->Report( msg );
             }
 
@@ -272,7 +272,7 @@
                     msg.Printf( _( "*** Warning: Component '%s' footprint ID '%s' is not "
                                    "valid. ***\n" ),
                                 GetChars( component->GetReference() ),
-                                component->GetFPID().GetFootprintName().c_str() );
+                                wxString( component->GetFPID().GetFootprintName() ).wc_str() );
                     aReporter->Report( msg );
                 }
 
@@ -294,7 +294,7 @@
                     msg.Printf( _( "*** Warning: component '%s' footprint '%s' was not found in "
                                    "any libraries in the footprint library table. ***\n" ),
                                 GetChars( component->GetReference() ),
-                                component->GetFPID().GetFootprintName().c_str() );
+                                wxString( component->GetFPID().GetFootprintName() ).wc_str() );
                     aReporter->Report( msg );
                 }

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