Invalid Command Line

[aleks-zer0]

Python version: 2.7.15 x64
BugID Version: 2018-10-17

When fuzzing EDGE on win10 x64 version 1803(build 17134.376), sometimes this happens:

Then it waits for user to press OK, and a few more minutes later, it restarts and start generating new .html tests. Btw, i'm using the setup described on the blog: https://bugid.skylined.nl/20181017001.html

[aleks-zer0]

Correction, the bug doesn't happen just sometimes, it happens in 8 out of 10 iterations. Something about UWP app debugging?

[aleks-zer0]

@SkyLined @j00sean

[j00sean]

it's a known issue caused by windbg. Discussed over here:
https://twitter.com/berendjanwever/status/1052469149430153216
@SkyLined is already aware of it.

[aleks-zer0]

Thanks. So as i can see on the thread, no solution is found yet :(

[SkyLined]

Yes: the problem is in Microsoft Debugging Tools for Windows AFAICT so I cannot fix it. I also do not know what causes it, nor do I know how to work around it.

I do have plans to allow BugId to work as a JIT debugger which should make this problem non-existent. Note that this would be a mayor code rewrite which will require quite some time to implement so don't hold your breath.

You can create a wrapper for EdgeHTML and use that; this will allow you to fuzz Edge's HTML rendering and JavaScript engines without actually using Edge. That should be faster and less error prone. I have plans to create and publish such a wrapper myself for this purpose.

[j00sean]

https://github.com/j00sean/SimpleWebView

[SkyLined]

I'll leave this open even if I cannot fix it as it has not been resolved and this bug might help others work around it.

[aleks-zer0]

Just figured out that on fresh win10 x64 v1703.15063.608 this is not an issue and works just fine, but after updating to 1803.17134.376 it starts happening again. It seems like EDGE is the actual problem, maybe they switched it to full-UWP app or something?

[j00sean]

yeah man, this annoying issue starts with April updates as i posted on other issue. Anyone has tested on 1809? I have no received the update and it's not available yet from free vms (https://developer.microsoft.com/en-us/microsoft-edge/tools/vms/). I read that this update was retired by MS. But it should be available now or very soon.

[SkyLined]

Work around: I confirmed the following allows you to use BugId with Edge:

1. Start Edge (either in BugId or manually)
2. Terminate browser_broker.exe once it is started.
3. Terminate Edge
4. Start Edge in BugId.

I'll see if I can add code to do this automatically.

[aleks-zer0]

Still not working for me, same message pops up. Also, immediately after killing browser_broker.exe, it spawns again :(
EDIT: After several tries, it suddenly works??? How? Will keep monitoring it to see for how long it will work.
EDIT2: Ok, it pops again :( i would really like to understand what is happening here and why it works in 1 out of 10 cases..

[SkyLined]

EDIT2: Ok, it pops again :( i would really like to understand what is happening here and why it works in 1 out of 10 cases..

Oh, we all do.... we all do... :'(

[SkyLined]

I think this issue no longer exists, please let me know if it does.