fix(sandbox): fix data corruption in sync --down and hang in sync --up#93
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fix(sandbox): fix data corruption in sync --down and hang in sync --up#93
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The sandbox SSH server used tokio::spawn fire-and-forget for each stdout/stderr chunk, which provided no ordering guarantee under tokio's work-stealing scheduler. Under load, chunks arrived out-of-order, corrupting tar streams during download. Replace tokio::spawn with runtime.block_on() to ensure each chunk is fully sent before reading the next. Remove AsyncWriteExt::shutdown() from the SSH proxy's copy helper to prevent gateways from treating TCP half-close as full-close and truncating in-flight downloads. Implement channel_eof handler on the sandbox SSH server to close the child process stdin when the client signals EOF. Without this, commands like 'cat | tar xf -' used by sync --up would hang waiting for stdin EOF indefinitely. Add ValueHint::AnyPath to the --up argument for shell completion. Signed-off-by: Piotr Mlocek <pmlocek@nvidia.com>
Add Rust unit tests verifying that dropping the mpsc sender (the mechanism channel_eof uses) closes the child's stdin pipe and delivers all buffered data before EOF. These tests would hang without the channel_eof fix. Add a 512 KiB large-file round-trip to the E2E sync bash test with SHA-256 checksum verification. Small test files fit in a single SSH chunk and cannot trigger the data ordering bug that corrupted tar streams. Signed-off-by: Piotr Mlocek <pmlocek@nvidia.com>
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#93) The sandbox SSH server used tokio::spawn fire-and-forget for each stdout/stderr chunk, which provided no ordering guarantee under tokio's work-stealing scheduler. Under load, chunks arrived out-of-order, corrupting tar streams during download. Replace tokio::spawn with runtime.block_on() to ensure each chunk is fully sent before reading the next. Remove AsyncWriteExt::shutdown() from the SSH proxy's copy helper to prevent gateways from treating TCP half-close as full-close and truncating in-flight downloads. Implement channel_eof handler on the sandbox SSH server to close the child process stdin when the client signals EOF. Without this, commands like 'cat | tar xf -' used by sync --up would hang waiting for stdin EOF indefinitely. Add ValueHint::AnyPath to the --up argument for shell completion.
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Summary
tokio::spawnfire-and-forget for each stdout/stderr chunk, which provided no ordering guarantee under tokio's work-stealing scheduler. Under load, chunks arrived out-of-order, corrupting tar streams. Replaced withruntime.block_on()to ensure sequential delivery.SshHandlernever implementedchannel_eof. Without it, the child process stdin was never closed when the client signaled EOF, socat | tar xf -waited indefinitely. Addedchannel_eofhandler that drops the input sender.ValueHint::AnyPathto the--upargument for shell path completion.Test Plan
channel_eofuses) closes the child's stdin pipe and delivers all buffered data before EOF. Tests use a 5s timeout and would hang without the fix.cargo test -p navigator-sandboxpasses (169 tests).