Bug 217733 – [iOS] Allow additional sysctl reads needed by image decoding

• Component: WebKit Misc.
• Status: RESOLVED FIXED

[Brent Fulgham]

Telemetry on iOS 14 shows that we are hitting some sandbox violations during image decoding:

    hw.byteorder
    hw.cachelinesize_compat
    hw.vectorunit

We also see that this is being read, but not used, so we can just silence the warning:

    hw.cpufrequency_compat

[Brent Fulgham]

<rdar://problem/68649171>

[Brent Fulgham]

Created attachment 411377 [details]
Patch

[Per Arne Vollan]

Comment on attachment 411377 [details]
Patch

R=me.

[Alexey Proskuryakov]

Comment on attachment 411377 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=411377&action=review

> Source/WebKit/Resources/SandboxProfiles/ios/com.apple.WebKit.WebContent.sb:647
> +          "hw.cpufrequency_compat"
> +          "sysctl.proc_native"))

It would be useful to have comments with radar numbers that track removing the need for these. It's not great to have deny-with-no-report rules. We add them for cases that we know is benign, but once they are in the profile, they start affecting all future scenarios, some of which can result in hard to diagnose bugs.

[EWS]

Committed r268507: <https://trac.webkit.org/changeset/268507>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 411377 [details].