Fix memory leak in ComStub when reads fail #3600
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drvReceiveIn passes ownership of recvBuffer, but ComStub only took care of deallocating the buffer if the read operation succeeded.
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| ComCfg::FrameContext emptyContext; // ComStub knows nothing about the received bytes, so use an empty context | ||
| this->dataOut_out(0, recvBuffer, emptyContext); | ||
| } else { | ||
| this->drvReceiveReturnOut_out(0, recvBuffer); |
Check warning
Code scanning / CodeQL
Unchecked function argument Warning
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|
@thomas-bc this looks right to me, but I'd prefer you to review. |
thomas-bc
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May 14, 2025
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Good catch, thank you!
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Change Description
drvReceiveIn passes ownership of recvBuffer, but ComStub only took care of deallocating the buffer if the read operation succeeded. If a communications driver indicates that a read did not succeed (for example with status RECV_NO_DATA), the buffer is lost and memory is leaked.
Rationale
Memory leaks cause FSW to fail to operate correctly.
Testing/Review Recommendations
This should probably be unit tested to prevent regressions, but that's not covered in this PR.
Future Work
It would be worth thinking about how we could avoid these sorts of buffer handling problems in the future.