fix: harden fs and net handlers - #68
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…-root guard Signed-off-by: danbugs <danilochiarlone@gmail.com>
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Pull request overview
This PR hardens host-side filesystem and networking RPC handlers to reduce guest-driven resource exhaustion and prevent host-thread stalls during socket I/O. It fits into the host crate’s tool/handler layer where guest calls are translated into constrained host operations.
Changes:
- Set read/write timeouts on sockets returned by
accept()so accepted connections can’t block host threads indefinitely. - Add caps/guards in filesystem handlers: limit
fs_listdirectory enumeration size, reject oversizedfs_write_bytesoffsets, and preventfs_unlinkfrom removing the mount root.
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danbugs
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Signed-off-by: danbugs <danilochiarlone@gmail.com>
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Linux Benchmarks
Details
| Benchmark suite | Current: 0dcbe53 | Previous: 4c053f6 | Ratio |
|---|---|---|---|
hello_world (median) |
20 ms |
20 ms |
1 |
pandas (median) |
110 ms |
90 ms |
1.22 |
density (per VM) |
7 MB |
7 MB |
1 |
snapshot (disk) |
385 MiB |
385 MiB |
1 |
This comment was automatically generated by workflow using github-action-benchmark.
danbugs
enabled auto-merge
May 17, 2026 08:16
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Windows Benchmarks
Details
| Benchmark suite | Current: 0dcbe53 | Previous: 4c053f6 | Ratio |
|---|---|---|---|
hello_world (median) |
272 ms |
181 ms |
1.50 |
pandas (median) |
876 ms |
557 ms |
1.57 |
density (per VM) |
6 MB |
6 MB |
1 |
snapshot (disk) |
392 MiB |
392 MiB |
1 |
This comment was automatically generated by workflow using github-action-benchmark.
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Summary
accept()returns a new socket that doesn't inherit parent timeouts, leavingnet_recvon accepted connections able to block the host thread indefinitelyfs_write_bytesoffset toMAX_TRUNCATE_LEN(1 GiB) — previously a guest could pass multi-TB offsets to create sparse files, circumventing the truncate capMAX_DIR_ENTRIES(100k) cap tofs_listto prevent host OOM on directories with millions of entriesfs_unlinkagainst deleting the mount root directory itselfTest plan
cargo test --libpasses (56 tests)cargo clippycleancargo fmtclean