Bug 141934 – [Mac][WK2] ASSERTION FAILED: m_sendPort in IPC::Connection::open()

• Component: WebKit2
• Status: RESOLVED FIXED

[Chris Dumez]

I recently hit the following assertion while navigating:

ASSERTION FAILED: m_sendPort
/Volumes/Data/cdumez/WebKit/OpenSource/Source/WebKit2/Platform/IPC/mac/ConnectionMac.mm(182) : bool IPC::Connection::open()
1   0x115764cb0 WTFCrash
2   0x111f263ba IPC::Connection::open()
3   0x111ef2344 WebKit::ChildProcess::initialize(WebKit::ChildProcessInitializationParameters const&)
4   0x11240ead9 void WebKit::XPCServiceInitializer<WebKit::WebProcess, WebKit::XPCServiceInitializerDelegate>(WTF::OSObjectPtr<_xpc_connection_s*>, void*)
5   0x11240e8a1 WebContentServiceInitializer
6   0x10ad6868d invocation function for block in WebKit::XPCServiceEventHandler(NSObject<OS_xpc_object>*)
7   0x7fff8a388d51 _xpc_connection_call_event_handler
8   0x7fff8a3888cf _xpc_connection_mach_event
9   0x7fff90dd20f8 _dispatch_client_callout4
10  0x7fff90dd31a3 _dispatch_mach_msg_invoke
11  0x7fff90dd0154 _dispatch_queue_drain
12  0x7fff90dd1a10 _dispatch_mach_invoke
13  0x7fff90dd8b02 _dispatch_main_queue_callback_4CF
14  0x7fff8f93d939 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__
15  0x7fff8f8f8d8f __CFRunLoopRun
16  0x7fff8f8f82d8 CFRunLoopRunSpecific
17  0x7fff8b23663f RunCurrentEventLoopInMode
18  0x7fff8b2363ba ReceiveNextEventCommon
19  0x7fff8b2361fb _BlockUntilNextEventMatchingListInModeWithFilter
20  0x7fff864abe3d _DPSNextEvent
21  0x7fff864ab440 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:]
22  0x7fff864a1133 -[NSApplication run]
23  0x7fff8641d814 NSApplicationMain
24  0x7fff8a398958 _xpc_objc_main
25  0x7fff8a39a060 _parse_sysctl_once
26  0x10ad68185 main
27  0x7fff8f4495c9 start

I had a very quick look and the culprit might be XPCServiceInitializerDelegate::getConnectionIdentifier() which returns true unconditionally although xpc_dictionary_copy_mach_send() can return MACH_PORT_NULL. I am not familiar with this code though.

[Chris Dumez]

Created attachment 247166 [details]
Patch

[WebKit Commit Bot]

Comment on attachment 247166 [details]
Patch

Clearing flags on attachment: 247166

Committed r180606: <http://trac.webkit.org/changeset/180606>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Alexey Proskuryakov]

Doesn't this make IPC problems harder to detect? Instead of an assertion, we now just get a mysterious exit with no diagnostics at all.