REGRESSION: ( r240978-r240985 ) [ iOS Release ] Layout Test imported/w3c/web-platform-tests/xhr/send-redirect-post-upload.htm is crashing

[Truitt Savell]

The following layout test is failing on iOS Release

imported/w3c/web-platform-tests/xhr/send-redirect-post-upload.htm

Probable cause:

Test began crashing constantly on iOS release. I was able to reproduce locally but there is a gap in usable builds between r240978-r240985. the test passes on 240978 and crashes on r240985. There is no stderr for the crash. The test is already a constant failure. 

Flakiness Dashboard:

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=imported%2Fw3c%2Fweb-platform-tests%2Fxhr%2Fsend-redirect-post-upload.htm

Crash:
https://build.webkit.org/results/Apple%20iOS%2012%20Simulator%20Release%20WK2%20(Tests)/r241280%20(2553)/imported/w3c/web-platform-tests/xhr/send-redirect-post-upload-crash-log.txt

[Alex Christensen]

This is a CFNetwork bug.  This won't be fixed by an open source change.

[Alexey Proskuryakov]

> This is a CFNetwork bug.  This won't be fixed by an open source change.

Alex, are you saying that this is not a regression in fact, and the bisection was wrong?

Otherwise, we must have done something to start triggering this bug, so we should undo that something.

[Alex Christensen]

I'll look into whether this was caused by https://trac.webkit.org/changeset/240984/webkit

[Alex Christensen]

Created attachment 362085 [details]
Patch

[Geoffrey Garen]

Comment on attachment 362085 [details]
Patch

> FormCreationContext* formContext = static_cast<FormCreationContext*>(context);

If you use adoptRef here, you can avoid the manual delete below.

auto formContext = adoptRef(...);
...
callOnMainThread([formContext]) { };

[Alex Christensen]

FormCreationContext is not refcounted.  I could call the std::unique_ptr constructor, but that would be less symmetric than this new/delete use which mirrors another new/delete pair in this file.

[Alex Christensen]

http://trac.webkit.org/r241594

[Radar WebKit Bug Importer]

<rdar://problem/48116418>

[Alex Christensen]

See rdar://problem/28233746

[Alex Christensen]

Reopening to attach new patch.

[Alex Christensen]

Created attachment 362434 [details]
Patch

[Alex Christensen]

rdar://problem/48211292

[Alex Christensen]

http://trac.webkit.org/r242367

[Shawn Roberts]

Test is still crashing or is a flaky failure on Peace iOS simulator

Dashboard :

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=imported%2Fw3c%2Fweb-platform-tests%2Fxhr%2Fsend-redirect-post-upload.htm

Reproduced with:

run-webkit-tests imported/w3c/web-platform-tests/xhr/send-redirect-post-upload.htm --iterations 20 -f --ios-simulator

Crash Log :

https://build.webkit.org/results/Apple%20iOS%2012%20Simulator%20Release%20WK2%20(Tests)/r242534%20(2989)/imported/w3c/web-platform-tests/xhr/send-redirect-post-upload-crash-log.txt

Process:               com.apple.WebKit.Networking.Development [21918]
Path:                  /Volumes/VOLUME/*/WebKit.framework/XPCServices/com.apple.WebKit.Networking.xpc/com.apple.WebKit.Networking.Development
Identifier:            com.apple.WebKit.Networking.Development
Version:               608+ (608.1.6+)
Code Type:             X86-64 (Native)
Parent Process:        launchd_sim [16059]
Responsible:           com.apple.WebKit.Networking.Development [21918]
User ID:               501

Date/Time:             2019-03-06 04:16:11.319 -0800
OS Version:            Mac OS X 10.13.6 (17G65)
Report Version:        12
Anonymous UUID:        08BAA9A8-3D60-DCF9-81D2-FF44C6DAE18D


Time Awake Since Boot: 650000 seconds

System Integrity Protection: disabled

Crashed Thread:        9  Dispatch queue: com.apple.CFNetwork.Connection

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_INVALID_ADDRESS at 0x0000000000000058
Exception Note:        EXC_CORPSE_NOTIFY

Termination Signal:    Segmentation fault: 11
Termination Reason:    Namespace SIGNAL, Code 0xb
Terminating Process:   exc handler [0]

VM Regions Near 0x58:
--> 
    __TEXT                 000000010b840000-000000010b841000 [    4K] r-x/rwx SM=COW  /Volumes/VOLUME/*/WebKit.framework/XPCServices/com.apple.WebKit.Networking.xpc/com.apple.WebKit.Networking.Development

Application Specific Information:
CoreSimulator 581.2 - Device: Managed 6 - Runtime: iOS 12.1 (16B91) - DeviceType: iPhone SE

Thread 0:: Dispatch queue: com.apple.main-thread
0   libsystem_kernel.dylib        	0x000000010f6cf20a mach_msg_trap + 10
1   libsystem_kernel.dylib        	0x000000010f6ce724 mach_msg + 60
2   com.apple.CoreFoundation      	0x000000010df071b4 __CFRunLoopServiceMachPort + 212
3   com.apple.CoreFoundation      	0x000000010df017e9 __CFRunLoopRun + 1689

[Alex Christensen]

Reopening to attach new patch.

[Alex Christensen]

Created attachment 364041 [details]
Patch

[WebKit Commit Bot]

Comment on attachment 364041 [details]
Patch

Clearing flags on attachment: 364041

Committed r242723: <https://trac.webkit.org/changeset/242723>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.