Fix bug of release_buffer

[TheSilentDawn]

Env

• Host: Ubuntu 22
• Docker
• Target: Ubuntu 18.04

Problem

While running command cargo run --release -- -c -o out ../build/Sodor3Stage.toml, I get the following error information

# From fuzzer

warning: `kfuzz` (bin "kfuzz") generated 25 warnings (run `cargo fix --bin "kfuzz"` to apply 25 suggestions)

    Finished `release` profile [optimized] target(s) in 0.01s

     Running `target/release/kfuzz -c -o out ../build/Sodor3Stage.toml`

Fuzzing Sodor3Stage

Instrumented on:   2025-12-01T14:33:16+08:00

Coverage Signals:  187

Input Fields:      4

Total Input Width: 35

Allocated Bytes per Input:    8

Allocated Bytes for Coverage: 190

Test Buffer:     1024 KiB

Coverage Buffer: 1024 KiB

Max Inputs: 21845



thread 'main' (10982) panicked at src/run/shmem.rs:206:9:

assertion `left == right` failed: tx pipe was closed unexpectedly!

  left: 0

 right: 8

note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

# From Server
/workspace/rfuzz/build/Sodor3Stage_server

Fuzz Server for Sodor3Stage

Allocated Bytes per Input:    8

Allocated Bytes per Coverage: 190

created tx fifo

created rx fifo

opened tx fifo

opened rx fifo

Sodor3Stage_server: ../../verilator/fpga_queue.cpp:96: bool FPGAQueueFuzzer::acquire_buffer(): Assertion `test_in_id == -1' failed.

Makefile:125: recipe for target 'run' failed

make: *** [run] Aborted (core dumped)

Under help of AI, it looks like the code of

rfuzz/verilator/fpga_queue.cpp

Line 109 in 651f28f

if(coverage_out_id > 0 && test_in_id > 0) {

is too strict due to different linux distrubute version.
As a result, I change it to

void FPGAQueueFuzzer::release_buffer() {
	// release in reverse order
//	if(coverage_out_id > 0 && test_in_id > 0) {
	if(coverage_out_id != -1 && test_in_id != -1) {

I'm not sure if AL response is correct, but it works for me. If possible, could u please help to double check the code. Thanks