Log telemetry for IOUserClient lookups

• Component: WebKit Misc.
• Status: RESOLVED FIXED

[Brent Fulgham]

We should use telemetry to make sure that every instance of an IOKit class we allow in our sandbox is actually needed by something for valid purposes.

Ideally, we would move as many of these out of the WebContent process as possible.

This telemetry will be a good first step in seeing if there is any low-hanging fruit.

[Brent Fulgham]

<rdar://problem/57987372>

[Brent Fulgham]

Created attachment 386127 [details]
Patch

[Per Arne Vollan]

Comment on attachment 386127 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=386127&action=review

R=me.

> Source/WebKit/Resources/SandboxProfiles/ios/com.apple.WebKit.WebContent.sb:451
>          (iokit-user-client-class "AppleJPEGDriverUserClient")
>          (iokit-user-client-class "IOSurfaceAcceleratorClient")

No telemetry for these?

> Source/WebKit/WebProcess/com.apple.WebProcess.sb.in:564
>      (iokit-user-client-class "AppleMultitouchDeviceUserClient")
>      (iokit-user-client-class "AppleUpstreamUserClient")

Ditto.

[Brent Fulgham]

Comment on attachment 386127 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=386127&action=review

>> Source/WebKit/Resources/SandboxProfiles/ios/com.apple.WebKit.WebContent.sb:451
>>          (iokit-user-client-class "IOSurfaceAcceleratorClient")
> 
> No telemetry for these?

I think we expect to be using these, so telemetry won't be that useful (everyone will always have these). But if we move these features to the GPU Process we should add telemetry, too, and consider removing them.

>> Source/WebKit/WebProcess/com.apple.WebProcess.sb.in:564
>>      (iokit-user-client-class "AppleUpstreamUserClient")
> 
> Ditto.

Actually, I'm not sure if we use these. I'll add them.

[Brent Fulgham]

Committed r253798: <https://trac.webkit.org/changeset/253798>