Safari Content Blocker Crash (OOM) when passing 6MB of data

Number:rdar://51064465 Date Originated:May 23 2019
Status:Open Resolved:
Product:iOS Safari Services Product Version:12.3
Classification: Reproducible:
Starting iOS 12.3 Safari Content Blocker extension cannot handle input of large amounts of JSON data.
The same code didn't crash in iOS 11 – 12.2

Steps to Reproduce:
Pass any data of 6MB or more to NSExtensionContext completeRequest method in Safari Content Blocker extension request handler

Expected Results:
Extension does not crash

Actual Results:
Extension exceeds 12MB memory limit and crashes

iOS 12.3


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