Fix MapBuffer OOB read vulnerability in release builds - #55296
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Summary: ## Changelog: [Internal] [Fixed] - Fix MapBuffer OOB read vulnerability in release builds This fixes a security vulnerability where MapBuffer accessors could leak memory or crash when handling missing keys in release builds. **Problem:** The `react_native_assert` macro is defined as `((void)0)` when `REACT_NATIVE_DEBUG` is not defined (production builds). This means the assertions in `getInt`, `getLong`, and `getDouble` are completely stripped out in release builds. When `getKeyBucket` returns -1 (key not found), the code proceeds to read from an invalid offset, causing: - Out-of-bounds memory reads - Information disclosure (leaking sensitive data) - Potential crashes **Solution:** Added runtime checks that work in release builds (debug build will abort at react_native_assert). This approach will not trigger more crash in release build. **Affected methods:** - `MapBuffer::getInt()` - `MapBuffer::getLong()` - `MapBuffer::getDouble()` Note: `getBool()` and `getString()` are protected because they call `getInt()` internally. [Session trajectory link](https://www.internalfb.com/intern/devai/devmate/inspector/?id=T247828667-0acc36ee-5abf-4f89-a444-3f8e1c959b51) Reviewed By: javache Differential Revision: D91478548
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Summary:
Changelog:
[Internal] [Fixed] - Fix MapBuffer OOB read vulnerability in release builds
This fixes a security vulnerability where MapBuffer accessors could leak memory or crash when handling missing keys in release builds.
Problem:
The
react_native_assertmacro is defined as((void)0)whenREACT_NATIVE_DEBUGis not defined (production builds). This means the assertions ingetInt,getLong, andgetDoubleare completely stripped out in release builds. WhengetKeyBucketreturns -1 (key not found), the code proceeds to read from an invalid offset, causing:Solution:
Added runtime checks that work in release builds (debug build will abort at react_native_assert). This approach will not trigger more crash in release build.
Affected methods:
MapBuffer::getInt()MapBuffer::getLong()MapBuffer::getDouble()Note:
getBool()andgetString()are protected because they callgetInt()internally.Session trajectory link
Differential Revision: D91478548