Bug 157830 – AX: Crash when backspacing in number field with spin button

• Component: Accessibility
• Status: RESOLVED FIXED

[chris fleizach]

Backspacing repeatedly with VoiceOver on in an input type="number" will eventually crash

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   com.apple.WebCore             	0x00007fff94f6312a WebCore::AXObjectCache::platformGenerateAXID() const + 10
1   com.apple.WebCore             	0x00007fff94f62e3b WebCore::AXObjectCache::getOrCreate(WebCore::AccessibilityRole) + 363
2   com.apple.WebCore             	0x00007fff94f0a816 WebCore::AccessibilitySpinButton::addChildren() + 38
3   com.apple.WebCore             	0x00007fff94ef63c2 WebCore::AccessibilityObject::updateChildrenIfNecessary() + 66
4   com.apple.WebCore             	0x00007fff94ef084d WebCore::AccessibilityObject::updateBackingStore() + 77
5   com.apple.WebCore             	0x00007fff95ad83ed -[WebAccessibilityObjectWrapperBase updateObjectBackingStore] + 61
6   com.apple.WebCore             	0x00007fff95ae1f47 -[WebAccessibilityObjectWrapper accessibilityAttributeValue:] + 39
7   com.apple.AppKit              	0x00007fff8b33d164 NSAccessibilityGetObjectForAttributeUsingLegacyAPI + 392
8   com.apple.AppKit              	0x00007fff8b33b7d8 _NSAccessibilityEntryPointValueForAttribute + 1879
9   com.apple.AppKit              	0x00007fff8bc41ca4 -[NSObject(NSRemoteUIElementAccessibility) accessibilityPresenterProcessIdentifier] + 111
10  com.apple.AppKit              	0x00007fff8b468ef0 NSAccessibilityCreateAXUIElementRef + 883
11  com.apple.AppKit              	0x00007fff8b6d3659 ConvertOutgoingValue + 1733
12  com.apple.AppKit              	0x00007fff8b6d3052 ConvertOutgoingValue + 190
13  com.apple.AppKit              	0x00007fff8b6d4c12 CopyAttributeValues + 289
14  com.apple.HIServices          	0x00007fff89f86018 _AXXMIGCopyAttributeValues + 308
15  com.apple.HIServices          	0x00007fff89f8ee37 _XCopyAttributeValues + 512
16  com.apple.HIServices          	0x00007fff89f68dad mshMIGPerform + 199
17  com.apple.CoreFoundation      	0x00007fff83324839 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 41
18  com.apple.CoreFoundation      	0x00007fff833247a9 __CFRunLoopDoSource1 + 473
19  com.apple.CoreFoundation      	0x00007fff83315e1b __CFRunLoopRun + 2171
20  com.apple.CoreFoundation      	0x00007fff83315338 CFRunLoopRunSpecific + 296
21  com.apple.HIToolbox           	0x00007fff829f4935 RunCurrentEventLoopInMode + 235
22  com.apple.HIToolbox           	0x00007fff829f476f ReceiveNextEventCommon + 432
23  com.apple.HIToolbox           	0x00007fff829f45af _BlockUntilNextEventMatchingListInModeWithFilter + 71
24  com.apple.AppKit              	0x00007fff8b31f0ee _DPSNextEvent + 1067
25  com.apple.AppKit              	0x00007fff8b6eb943 -[NSApplication _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 454
26  com.apple.AppKit              	0x00007fff8b314fc8 -[NSApplication run] + 682
27  com.apple.AppKit              	0x00007fff8b297520 NSApplicationMain + 1176
28  libxpc.dylib                  	0x00007fff944aff6c _xpc_objc_main + 793
29  libxpc.dylib                  	0x00007fff944b16bb xpc_main + 494
30  com.apple.WebKit.WebContent   	0x0000000101d90b4a 0x101d90000 + 2890
31  libdyld.dylib                 	0x00007fff86b8c5ad start + 1




<rdar://problem/24458212>

[chris fleizach]

Created attachment 279225 [details]
Patch

[Build Bot]

Comment on attachment 279225 [details]
Patch

Attachment 279225 [details] did not pass mac-ews (mac):
Output: http://webkit-queues.webkit.org/results/1341494

New failing tests:
accessibility/mac/html5-input-number.html
accessibility/spinbutton-crash.html

[Build Bot]

Created attachment 279226 [details]
Archive of layout-test-results from ews102 for mac-yosemite

The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: ews102  Port: mac-yosemite  Platform: Mac OS X 10.10.5

[Build Bot]

Comment on attachment 279225 [details]
Patch

Attachment 279225 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.webkit.org/results/1341495

New failing tests:
accessibility/mac/html5-input-number.html
accessibility/spinbutton-crash.html

[Build Bot]

Created attachment 279228 [details]
Archive of layout-test-results from ews105 for mac-yosemite-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews105  Port: mac-yosemite-wk2  Platform: Mac OS X 10.10.5

[Build Bot]

Comment on attachment 279225 [details]
Patch

Attachment 279225 [details] did not pass mac-debug-ews (mac):
Output: http://webkit-queues.webkit.org/results/1341532

New failing tests:
accessibility/mac/html5-input-number.html
accessibility/spinbutton-crash.html

[Build Bot]

Created attachment 279230 [details]
Archive of layout-test-results from ews117 for mac-yosemite

The attached test failures were seen while running run-webkit-tests on the mac-debug-ews.
Bot: ews117  Port: mac-yosemite  Platform: Mac OS X 10.10.5

[Joanmarie Diggs]

Looks like your tests need some adjustment.

That said.... Sanity checks seem like a good idea, but if you don't mind my asking: Is backspacing over the contents of the input causing spin button parts to become detached? If so, that strikes me as odd and possibly worthy of a sentence in your ChangeLog.

Also, "safe guards" in this context is one word.

[chris fleizach]

(In reply to comment #8)
> Looks like your tests need some adjustment.
> 
> That said.... Sanity checks seem like a good idea, but if you don't mind my
> asking: Is backspacing over the contents of the input causing spin button
> parts to become detached? If so, that strikes me as odd and possibly worthy
> of a sentence in your ChangeLog.
> 

That is what it seems like. I can't figure out why one of these tests is failing now so this is requiring some more work sadly

> Also, "safe guards" in this context is one word.

Thanks

[Darin Adler]

Comment on attachment 279225 [details]
Patch

Setting review- since we don’t want to review this until after we resolve the crashing tests. Code changes look fine to me, by the way.

[Nan Wang]

Created attachment 283332 [details]
patch

It seems putting isDetachedFromParent() in updateObjectBackingStore will affect lots of stuff.

[WebKit Commit Bot]

Comment on attachment 283332 [details]
patch

Clearing flags on attachment: 283332

Committed r203083: <http://trac.webkit.org/changeset/203083>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.