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<think>
</think>
The provided log indicates a crash in the QEMU emulator due to a negative size parameter being passed to `memcpy`, which is detected by AddressSanitizer (ASan). This suggests there's a bug in the code that calls `memcpy` with an invalid size argument. The stack trace shows where this issue occurs, starting from `LLVMFuzzerInitialize` in `videzzo_qemu.c` and propagating through various QEMU initialization functions.
### Key Points:
1. **Crash Cause**: A negative size parameter is passed to `memcpy`, which is invalid and causes the program to abort.
2. **Location**: The issue occurs in `asan_interceptors_memintrinsics.cpp` at line 22, which intercepts memory operations for ASan.
3. **Stack Trace**:
- The crash originates from `LLVMFuzzerInitialize`.
- It propagates through QEMU's initialization functions (`qemu_init`, `machine_run_board_init`, etc.).
- The root cause likely lies in the hardware device initialization (`tosa_init`, `tc6393xb_init`, `nand_init`), where a negative size is being passed to `memcpy`.
### Steps to Investigate:
1. **Review Fuzzer Input**:
- Check the input provided to the fuzzer to ensure it's valid and doesn't trigger invalid memory operations.
2. **Inspect QEMU Initialization**:
- Look at the functions in `tosa_init`, `tc6393xb_init`, and `nand_init` to identify where an invalid size might be calculated or passed.
3. **Check Memory Operations**:
- Ensure all calls to `memcpy` (or similar functions) have valid, non-negative size parameters.
4. **Debug with ASan**:
- Use ASan's features to track memory allocations and detect the exact point where the invalid size is used.
### Conclusion:
The crash indicates a bug in QEMU's initialization process when using the fuzzer. The negative size parameter passed to `memcpy` suggests an issue in how memory operations are handled during device initialization. Investigating the functions in `tosa_init`, `tc6393xb_init`, and `nand_init` will help identify the root cause of this bug.
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