{"record":{"id":"47f8470588460761","repo":"ReFirmLabs/binwalk","slug":"failed-to-retrieve-next-file-from-the-queue","errorCode":null,"errorMessage":"Failed to retrieve next file from the queue","messagePattern":"Failed to retrieve next file from the queue","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"warning","filePath":"src/main.rs","lineNumber":164,"sourceCode":"    debug!(\n        \"Queuing initial target file: {}\",\n        binwalker.base_target_file\n    );\n\n    // Queue the initial file path\n    target_files.insert(target_files.len(), binwalker.base_target_file.clone());\n\n    /*\n     * Main loop.\n     * Loop until all pending thread jobs are complete and there are no more files in the queue.\n     */\n    while !target_files.is_empty() || workers.active_count() > 0 {\n        // If there are files waiting to be analyzed and there is at least one free thread in the pool\n        if !target_files.is_empty() && workers.active_count() < workers.max_count() {\n            // Get the next file path from the target_files queue\n            let target_file = target_files\n                .pop_front()\n                .expect(\"Failed to retrieve next file from the queue\");\n\n            // Spawn a new worker for the new file\n            spawn_worker(\n                &workers,\n                binwalker.clone(),\n                target_file,\n                cliargs.stdin && file_count == 0,\n                cliargs.extract,\n                cliargs.carve,\n                worker_tx.clone(),\n            );\n        }\n\n        // Don't spin CPU cycles if there is no backlog of files to analyze\n        if target_files.is_empty() {\n            let sleep_time = time::Duration::from_millis(1);\n            thread::sleep(sleep_time);\n        }","sourceCodeStart":146,"sourceCodeEnd":182,"githubUrl":"https://github.com/ReFirmLabs/binwalk/blob/26713972e3f9f52dc37d4a421c4554b0bd9e82ef/src/main.rs#L146-L182","documentation":"A panic in the main scheduling loop when target_files.pop_front() returns None. The loop guard checks !target_files.is_empty(), so this should be impossible; the panic indicates the internal invariant 'non-empty deque has a front element' was violated (e.g. by concurrent mutation or a logic bug elsewhere).","triggerScenarios":"Only reachable if target_files becomes empty between the is_empty() check and pop_front() — e.g. another thread mutating the deque concurrently, or a future code change moving the pop outside the guarded branch.","commonSituations":"Refactoring the scheduler loop to share target_files across threads without a mutex; a misordered check in modified code; it is effectively dead code in the current single-threaded loop.","solutions":["Verify no other code path mutates target_files while the loop runs","Restructure to make the invariant explicit: use `if let Some(target_file) = target_files.pop_front()` inside the branch instead of expect","If sharing across threads, protect the deque with a Mutex or use a channel-based work queue","Confirm the installed binary matches the source you are reading (rebuild) in case the check was altered"],"exampleFix":"// before\nlet target_file = target_files\n    .pop_front()\n    .expect(\"Failed to retrieve next file from the queue\");\n// after\nlet Some(target_file) = target_files.pop_front() else {\n    continue;\n};","handlingStrategy":"type-guard","validationCode":"// before popping, re-check invariant explicitly\nif target_files.is_empty() { continue; }","typeGuard":"let Some(target_file) = target_files.pop_front() else { continue; };","tryCatchPattern":null,"preventionTips":["Prefer if-let/let-else over expect() for queue dequeues","Never share the deque across threads without synchronization","Keep the emptiness check and pop adjacent so no code can interleave","Rebuild from source to ensure running binary matches audited code"],"tags":["rust","panic","invariant","concurrency"],"backgroundTag":"internal-invariant-violation","analyzedSha":"26713972e3f9f52dc37d4a421c4554b0bd9e82ef","analyzedAt":"2026-09-06T21:38:04.941Z","contentChangedAt":"2026-09-06T21:38:04.941Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}