fix/TS-7542-double-free

[cadem]

Description

Please briefly describe the code changes in this pull request.

Checklist

Please check the items in the checklist if applicable.

• Is the user manual updated?
• Are the test cases passed and automated?
• Is there no significant decrease in test coverage?

[gemini-code-assist]

Summary of Changes

Hello @cadem, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request resolves a critical memory management issue, specifically a double-free bug identified as TS-7542. The change targets the transport layer's message handling, ensuring that memory associated with RPC message content is not deallocated redundantly. This enhancement improves system stability and prevents potential crashes related to incorrect memory deallocation.

Highlights

• Double-Free Prevention: A potential double-free vulnerability (TS-7542) has been addressed by commenting out a conditional rpcFreeCont call within the tmsgSendSyncReq function. This prevents pMsg->pCont from being freed prematurely if the sendSyncReqFp operation fails, ensuring proper memory management.

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[gemini-code-assist]

Code Review

This pull request addresses a critical double-free vulnerability in tmsgSendSyncReq. The fix, which comments out the memory deallocation on error, is correct because the callee (defaultMsgCb.sendSyncReqFp) is responsible for freeing the message content. Freeing it again in tmsgSendSyncReq would cause a double free.

However, I have found the same critical vulnerability in another function in the same file:

• tmsgSendReq: This function has identical logic to the original tmsgSendSyncReq. Its callee (sendReqFp) also frees the message content on error, which will lead to a double-free.

Additionally, tmsgPutToQueue follows a similar pattern and should be investigated to ensure it is not also vulnerable.

I strongly recommend fixing the critical issue in tmsgSendReq as part of this pull request to comprehensively address this type of vulnerability in the codebase.