Fix Memory Leak

[mstdokumaci]

Added error handling for cleanup of parse stack. Will prevent a special type of DoS attack.

[gemini-code-assist]

Summary of Changes

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This pull request addresses a potential memory leak by enhancing error handling within the message pack parsing logic. It ensures that critical resources are correctly deallocated even when unexpected errors occur, improving the robustness and stability of the parsing process.

Highlights

• Memory Leak Fix: Implemented errdefer to ensure proper cleanup of the parse stack in the PackWithLimits function, preventing potential memory leaks during error conditions.

Changelog

• src/msgpack.zig
  • Added errdefer to ensure cleanupParseStack is called on error.

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[gemini-code-assist]

Code Review

This change introduces an errdefer to call cleanupParseStack within the readComplex function. This ensures cleanup is performed on error paths, addressing a potential memory leak. The explicit calls to cleanupParseStack before return statements elsewhere in the same function are now redundant and could be removed to simplify the code.

[mstdokumaci]

Code Review

This change introduces an errdefer to call cleanupParseStack within the readComplex function. This ensures cleanup is performed on error paths, addressing a potential memory leak. The explicit calls to cleanupParseStack before return statements elsewhere in the same function are now redundant and could be removed to simplify the code.

Removed the explicit calls to cleanupParseStack and added a test to demonstrate the benefit of errdefer. Please review again.

[jinzhongjia]

Thx for your pr, I will review the code as soon as quickly

[jinzhongjia]

The overall modification to LGTM, replacing manual cleanup with errdefer, is the correct approach.

A minor issue: There is an unused writer variable (var writer = std.Io.Writer.fixed(&buffer);) in test "PackerIO: truncated array cleanup". It is not needed for the read test and should be removed.