[bug #42782] Crash when loading a gorm file

[Yavor Doganov]

Follow-up Comment #11, bug #42782 (project gnustep):

Yes, I used Gorm 1.2.20 + your latest changes.  Most probably it is not an
issue with Gorm at all.

I'd really wish to provide more information...  Perhaps I could put
breakpoints at some places and step through from there, this would at least
give you some clue, as blurry as that may be.  As Gorm is a fairly complex
program, I'm trying Vindaloo first.  I already figured out that Vindaloo
crashes in -[Document -makeWindowControllers], right after [self
addWindowController: ctrl]; ctrl is initalized properly with
-initWithWindowNibName: with [self windowNibName] as argument (which returns
@"Document").  Stepping from there:

(gdb) n
-[NSDocumentController openDocumentWithContentsOfURL:display:error:] (
    self=0x840c0a8, _cmd=0xb7f73648 <_OBJC_SELECTOR_TABLE+520>, url=0x840ae20,

    flag=1 ' 01', err=0xbffff4cc) at NSDocumentController.m:708
708           [self noteNewRecentDocument: document];
(gdb) n
710           if (flag && [self shouldCreateUI])
(gdb) n
712               [document showWindows];
(gdb) 

Program received signal SIGSEGV, Segmentation fault.
0xbfffef8a in ?? ()


Putting breakpoints further:

Breakpoint 2, -[NSDocument showWindows] (self=0x82a1268, 
    _cmd=0xb7edd828 <_OBJC_SELECTOR_TABLE+488>) at NSDocument.m:415
415     {
(gdb) po _window_controllers 
("<Controller: 0x83e54f8>")
(gdb) n
417                                           withObject: self];
(gdb) n
416       [_window_controllers makeObjectsPerformSelector: 
@selector(showWindow:)
(gdb) n
417                                           withObject: self];
(gdb) n

Program received signal SIGSEGV, Segmentation fault.
0xbfffef8a in ?? ()
....
Breakpoint 3, -[NSWindowController showWindow:] (
    self=0xb7edb1b8 <_OBJC_SELECTOR_TABLE+504>, 
    _cmd=0xb7edb1b8 <_OBJC_SELECTOR_TABLE+504>, sender=0x81fdb90)
    at NSWindowController.m:394
394     {
(gdb) n
395       NSWindow *window = [self window];
(gdb) po self
<Controller: 0x83e73e8>
(gdb) po [self window]

Program received signal SIGSEGV, Segmentation fault.
0xbfffef6a in ?? ()
....
Breakpoint 4, -[NSWindowController window] (self=0x83ea168, 
    _cmd=0xb7f680f0 <_OBJC_SELECTOR_TABLE+176>) at NSWindowController.m:297
297     {
(gdb) n
298       if (_window == nil && ![self isWindowLoaded])
(gdb) n
308           [self windowWillLoad];
(gdb) p _window
$5 = (struct NSWindow *) 0x0
(gdb) n
309           if (_owner != self &&
(gdb) po self
<Controller: 0x83ea168>
(gdb) po _owner
<Controller: 0x83ea168>
(gdb) n
315           [self loadWindow];
(gdb) n

Program received signal SIGSEGV, Segmentation fault.
....
Breakpoint 5, -[NSWindowController loadWindow] (self=0x83e5340, 
    _cmd=0xb7f68170 <_OBJC_SELECTOR_TABLE+304>) at NSWindowController.m:476
476     {
(gdb) n
479       if ([self isWindowLoaded]) 
(gdb) n
484       table = [NSDictionary dictionaryWithObject: _owner forKey: 
NSNibOwner];
(gdb) po table
value has been optimized out
(gdb) n
485       if ([NSBundle loadNibFile: [self windowNibPath]
(gdb) po self
<Controller: 0x83e5340>
(gdb) po [self windowNibPath]
/home/yavor/scratch/viewpdf.app-0.2dfsg1/ViewPDF.app/Resources/English.lproj/Document.gorm
(gdb) po _owner
<Controller: 0x83e5340>
(gdb) n
487                     withZone: [_owner zone]])
(gdb) n
485       if ([NSBundle loadNibFile: [self windowNibPath]
(gdb) n
487                     withZone: [_owner zone]])
(gdb) n

Program received signal SIGSEGV, Segmentation fault.
0xbfffef8a in ?? ()
....
Breakpoint 6, +[NSBundle(NSBundleAdditions)
loadNibFile:externalNameTable:withZone:] (self=0xb79d43e0
<_OBJC_Class_NSBundle>, 
    _cmd=0xb7f68250 <_OBJC_SELECTOR_TABLE+528>, fileName=0x8268c18, 
    context=0x8267fe0, zone=0xb7a3f0c0 <default_zone>)
    at NSBundleAdditions.m:234
234     {
(gdb) n
235       NSNib *nib = [[NSNib alloc] initWithContentsOfURL: [NSURL
fileURLWithPath: fileName]];
(gdb) po fileName
/home/yavor/scratch/viewpdf.app-0.2dfsg1/ViewPDF.app/Resources/English.lproj/Document.gorm
(gdb) po [NSURL fileURLWithPath: fileName]
file://localhost/home/yavor/scratch/viewpdf.app-0.2dfsg1/ViewPDF.app/Resources/English.lproj/Document.gorm/
(gdb) po context
{NSOwner = "<Controller: 0x83e5568>"; }
(gdb) n
237                                                     withZone: zone];
(gdb) po nib
value has been optimized out
(gdb) n
235       NSNib *nib = [[NSNib alloc] initWithContentsOfURL: [NSURL
fileURLWithPath: fileName]];
(gdb) n
239       RELEASE(nib);
(gdb) n
235       NSNib *nib = [[NSNib alloc] initWithContentsOfURL: [NSURL
fileURLWithPath: fileName]];
(gdb) n
237                                                     withZone: zone];
(gdb) n
236       BOOL loaded = [nib instantiateNibWithExternalNameTable: context
(gdb) n

Program received signal SIGSEGV, Segmentation fault.
0xbfffef8a in ?? ()
....
Breakpoint 7, -[NSNib instantiateNibWithExternalNameTable:withZone:] (
    self=0x8411090, _cmd=0xb7ebc0d0 <_OBJC_SELECTOR_TABLE+208>, 
    externalNameTable=0x8410c28, zone=0xb7a3f0c0 <default_zone>) at
NSNib.m:152
152     {
(gdb) n
155                       withZone: zone];
(gdb) po _loader
<GSGormLoader: 0x84116c0>
(gdb) po _nibData
<474e5573 74657020 61726368 69766530 30303032 6166393a 30303030 30303135
3a303030 30303032 303a3030 30303030 30303a30 01310100 0e47534e 6962436f
6e746169 6e657200 00000131 0200084e 534f626a 65637400 00000000 30023103
00134e53 4d757461 626c6544 69637469 6f6e6172 79000000 00310400 ...(skipped)>
(gdb) po externalNameTable 
{NSOwner = "<Controller: 0x83e55c8>"; }
(gdb) n
153       return [_loader loadModelData: _nibData 
(gdb) n
155                       withZone: zone];
(gdb) n
153       return [_loader loadModelData: _nibData 
(gdb) n

Program received signal SIGSEGV, Segmentation fault.
0xbfffef8a in ?? ()
....
Breakpoint 8, -[GSGormLoader loadModelData:externalNameTable:withZone:] (
    self=0x83df480, _cmd=0xb7f09cb0 <_OBJC_SELECTOR_TABLE+112>, 
    data=0x83dfbc8, context=0x83de9d0, zone=0xb7a3f0c0 <default_zone>)
    at GSGormLoader.m:98
98      {
(gdb) n
104           if (data != nil)
(gdb) n
106               unarchiver = [[NSUnarchiver alloc] 
(gdb) n
107                              initForReadingWithData: data];
(gdb) n
106               unarchiver = [[NSUnarchiver alloc] 
(gdb) n
107                              initForReadingWithData: data];
(gdb) n
106               unarchiver = [[NSUnarchiver alloc] 
(gdb) 
108               if (unarchiver != nil)
(gdb) 
106               unarchiver = [[NSUnarchiver alloc] 
(gdb) 
108               if (unarchiver != nil)
108               if (unarchiver != nil)
(gdb) 
112                   NSDebugLog(@"Invoking unarchiver");
(gdb) 
113                   [unarchiver setObjectZone: zone];
(gdb) 
114                   obj = [unarchiver decodeObject];
(gdb) 
113                   [unarchiver setObjectZone: zone];
(gdb) 
114                   obj = [unarchiver decodeObject];
(gdb) 

Program received signal SIGSEGV, Segmentation fault.
0xbfffef8a in ?? ()


I put a break on -[NSCoder decodeObject] here and there's a lot of stepping as
all the objects get decoded.  Then,

-[GSWindowTemplate initWithCoder:] (self=0x83e7bc0, 
    _cmd=0xb7a29268 <_OBJC_SELECTOR_TABLE+232>, coder=0x84118f8)
    at GSGormLoading.m:879
879       if (obj != nil)
(gdb) 
878       id obj = [super initWithCoder: coder];
(gdb) 
879       if (obj != nil)
(gdb) 
881           int version = [coder versionForClassName: @"GSWindowTemplate"];
(gdb) 
883           if (version == GSWINDOWT_VERSION)
(gdb) 
890           else if (version == 0)
(gdb) 
893               [coder decodeValueOfObjCType: @encode(BOOL) at: &_deferFlag]; 
     
(gdb) 
894               _autoPositionMask = GSWindowAutoPositionNone;
(gdb) 
895               _screenRect = [[_object screen] frame];
(gdb) 

Program received signal SIGSEGV, Segmentation fault.
0xbfffef8a in ?? ()


I restart the program putting another break here.  Trying to dereference
_object results in "No symbol "_object" in current context" so sending a
message to _object expectedly ends with a crash at runtime level.  FYI the
value of obj there is "<DocumentWindow: 0x83e9ab8>Number: 6 Title: Window".

This is with GUI 0.24.0 + your change from bug#42717 cherry-picked; built with
--disable-imagemagick and default optimization (-O2) on i386 (x86).  GCC
4.9.1, GCC runtime.

    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/bugs/?42782>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.gnu.org/