Stream: git-wasmtime

Topic: wasmtime / issue #2669 Regression: hard links created by ...

Wasmtime GitHub notifications bot (Feb 09 2023 at 08:52):

bjorn3 commented on issue #2669:

https://github.com/rust-lang/rust/pull/81984 has been merged. Can this be closed?

Wasmtime GitHub notifications bot (Feb 09 2023 at 15:53):

alexcrichton closed issue #2669:

_Originally reported on the Rust repo at https://github.com/rust-lang/rust/issues/82277_

I tried this code:

fn main() {
    std::fs::hard_link("/a", "/b").unwrap();
}

I compiled it with --target wasm32-wasi and executed with latest Wasmtime 0.23.0 with wasmtime --mapdir=/::. where the current directory contains valid file a.

I expected to see this happen:

A hard link b is created that points to a.

Instead, this happened:

It fails with an error:

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 28, kind: InvalidInput, message: "Invalid argument" }', temp.rs:2:36
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Error: failed to run main module `temp.wasm`

Caused by:
    0: failed to invoke command default
    1: wasm trap: unreachable
       wasm backtrace:
           0: 0x7b4c - <unknown>!__rust_start_panic
           1: 0x75e5 - <unknown>!rust_panic
           2: 0x71bd - <unknown>!std::panicking::rust_panic_with_hook::hb9189a2ae1f00dd6
           3: 0x6928 - <unknown>!std::panicking::begin_panic_handler::{{closure}}::ha38be87363679287
           4: 0x6869 - <unknown>!std::sys_common::backtrace::__rust_end_short_backtrace::h955bbbeea72dc4a0
           5: 0x7061 - <unknown>!rust_begin_unwind
           6: 0xd0a6 - <unknown>!core::panicking::panic_fmt::h904ce09f3cb14707
           7: 0xdbcc - <unknown>!core::option::expect_none_failed::ha29c9c4296a18e58
           8:  0xfee - <unknown>!core::result::Result<T,E>::unwrap::hcf72e0af954224e8
           9:  0x9b7 - <unknown>!temp::main::hdc57b3c35eac1777
          10:  0xac2 - <unknown>!core::ops::function::FnOnce::call_once::h9d9b1f2044973e11
          11:  0x8ac - <unknown>!std::sys_common::backtrace::__rust_begin_short_backtrace::h0d198c55a40ffd2e
          12:  0xdf2 - <unknown>!std::rt::lang_start::{{closure}}::he287b5106de2dbae
          13: 0x76f6 - <unknown>!std::rt::lang_start_internal::h81003f47a7b429a5
          14:  0xdc6 - <unknown>!std::rt::lang_start::h75812a9706ce1699
          15:  0x9e8 - <unknown>!__original_main
          16:  0x3f9 - <unknown>!_start
       note: run with `WASMTIME_BACKTRACE_DETAILS=1` environment variable to display more information

Meta

rustc --version --verbose:

rustc 1.49.0 (e1884a8e3 2020-12-29)
binary: rustc
commit-hash: e1884a8e3c3e813aada8254edfa120e85bf5ffca
commit-date: 2020-12-29
host: x86_64-unknown-linux-gnu
release: 1.49.0

wasmtime --version:

wasmtime 0.23.0

</p>
</details>

Other attempts

Equivalent C code

I've also tried to compile an equivalent C code:

#include <unistd.h>

int main() {
    return link("/a", "/b");
}

When this is compiled with WASI SDK clang --target=wasm32-wasi and executed with the same command in Wasmtime, it successfully creates the hardlink.

Node.js WASI

I've also tried to execute those Wasm files with Node.js WASI support, and both Wasm files create hard links successfully.

Older Wasmtime

Finally, I've tried to execute both with Wasmtime 0.22, and both also create hardlinks successfully, indicating a regression in Wasmtime itself.

Last updated: Dec 23 2024 at 12:05 UTC