Rollup merge of #129055 - Oneirical:fortanix-fortification, r=jieyouxu

Migrate `x86_64-fortanix-unknown-sgx-lvi` `run-make` test to rmake

Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).

The final Makefile! Every Makefile test is now claimed.

This is difficult to test due to the uncommon architecture it is specific to. I don't think it is in the CI (I didn't find it in `jobs.yml`, but if there is a way to test it, please do.

Locally, on Linux, it compiles and panics at the `llvm_filecheck` part (if I replace the `x86_64-fortanix-unknown-sgx` with `x86_64-unknown-linux-gnu`, of course), which is expected.

For this reason, the Makefile and associated script have been kept, but with a leading underscore.

src/tools/run-make-support/src/env.rs

@@ -24,3 +24,11 @@ pub fn env_var_os(name: &str) -> OsString {
 pub fn no_debug_assertions() -> bool {
     std::env::var_os("NO_DEBUG_ASSERTIONS").is_some()
 }
+
+/// A wrapper around [`std::env::set_current_dir`] which includes the directory
+/// path in the panic message.
+#[track_caller]
+pub fn set_current_dir<P: AsRef<std::path::Path>>(dir: P) {
+    std::env::set_current_dir(dir.as_ref())
+        .expect(&format!("could not set current directory to \"{}\"", dir.as_ref().display()));
+}

src/tools/run-make-support/src/lib.rs

@@ -64,7 +64,7 @@ pub use rustdoc::{bare_rustdoc, rustdoc, Rustdoc};
 pub use diff::{diff, Diff};
 
 /// Panic-on-fail [`std::env::var`] and [`std::env::var_os`] wrappers.
-pub use env::{env_var, env_var_os};
+pub use env::{env_var, env_var_os, set_current_dir};
 
 /// Convenience helpers for running binaries and other commands.
 pub use run::{cmd, run, run_fail, run_with_args};

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -11,4 +11,3 @@ run-make/macos-deployment-target/Makefile
 run-make/split-debuginfo/Makefile
 run-make/symbol-mangling-hashed/Makefile
 run-make/translation/Makefile
-run-make/x86_64-fortanix-unknown-sgx-lvi/Makefile

tests/run-make/x86_64-fortanix-unknown-sgx-lvi/rmake.rs

@@ -0,0 +1,96 @@
+// ignore-tidy-linelength
+// Reason: intel.com link
+
+// This security test checks that the disassembled form of certain symbols
+// is "hardened" - that means, the assembly instructions match a pattern that
+// mitigate potential Load Value Injection vulnerabilities.
+// To do so, a test crate is compiled, and certain symbols are found, disassembled
+// and checked one by one.
+// See https://github.com/rust-lang/rust/pull/77008
+
+// On load value injection:
+// https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/load-value-injection.html
+
+//@ only-x86_64-fortanix-unknown-sgx
+
+use run_make_support::{cmd, cwd, llvm_filecheck, llvm_objdump, regex, set_current_dir, target};
+
+fn main() {
+    let main_dir = cwd();
+    set_current_dir("enclave");
+    // HACK(eddyb) sets `RUSTC_BOOTSTRAP=1` so Cargo can accept nightly features.
+    // These come from the top-level Rust workspace, that this crate is not a
+    // member of, but Cargo tries to load the workspace `Cargo.toml` anyway.
+    cmd("cargo")
+        .env("RUSTC_BOOTSTRAP", "1")
+        .arg("-v")
+        .arg("run")
+        .arg("--target")
+        .arg(target())
+        .run();
+    set_current_dir(&main_dir);
+    // Rust has various ways of adding code to a binary:
+    // - Rust code
+    // - Inline assembly
+    // - Global assembly
+    // - C/C++ code compiled as part of Rust crates
+    // For those different kinds, we do have very small code examples that should be
+    // mitigated in some way. Mostly we check that ret instructions should no longer be present.
+    check("unw_getcontext", "unw_getcontext.checks");
+    check("__libunwind_Registers_x86_64_jumpto", "jumpto.checks");
+
+    check("std::io::stdio::_print::[[:alnum:]]+", "print.with_frame_pointers.checks");
+
+    check("rust_plus_one_global_asm", "rust_plus_one_global_asm.checks");
+
+    check("cc_plus_one_c", "cc_plus_one_c.checks");
+    check("cc_plus_one_c_asm", "cc_plus_one_c_asm.checks");
+    check("cc_plus_one_cxx", "cc_plus_one_cxx.checks");
+    check("cc_plus_one_cxx_asm", "cc_plus_one_cxx_asm.checks");
+    check("cc_plus_one_asm", "cc_plus_one_asm.checks");
+
+    check("cmake_plus_one_c", "cmake_plus_one_c.checks");
+    check("cmake_plus_one_c_asm", "cmake_plus_one_c_asm.checks");
+    check("cmake_plus_one_c_global_asm", "cmake_plus_one_c_global_asm.checks");
+    check("cmake_plus_one_cxx", "cmake_plus_one_cxx.checks");
+    check("cmake_plus_one_cxx_asm", "cmake_plus_one_cxx_asm.checks");
+    check("cmake_plus_one_cxx_global_asm", "cmake_plus_one_cxx_global_asm.checks");
+    check("cmake_plus_one_asm", "cmake_plus_one_asm.checks");
+}
+
+fn check(func_re: &str, mut checks: &str) {
+    let dump = llvm_objdump()
+        .input("enclave/target/x86_64-fortanix-unknown-sgx/debug/enclave")
+        .args(&["--syms", "--demangle"])
+        .run()
+        .stdout_utf8();
+    let re = regex::Regex::new(&format!("[[:blank:]]+{func_re}")).unwrap();
+    let func = re.find_iter(&dump).map(|m| m.as_str().trim()).collect::<Vec<&str>>().join(",");
+    assert!(!func.is_empty());
+    let dump = llvm_objdump()
+        .input("enclave/target/x86_64-fortanix-unknown-sgx/debug/enclave")
+        .args(&["--demangle", &format!("--disassemble-symbols={func}")])
+        .run()
+        .stdout_utf8();
+    let dump = dump.as_bytes();
+
+    // Unique case, must succeed at one of two possible tests.
+    // This is because frame pointers are optional, and them being enabled requires
+    // an additional `popq` in the pattern checking file.
+    if func_re == "std::io::stdio::_print::[[:alnum:]]+" {
+        let output = llvm_filecheck().stdin(&dump).patterns(checks).run_unchecked();
+        if !output.status().success() {
+            checks = "print.without_frame_pointers.checks";
+            llvm_filecheck().stdin(&dump).patterns(checks).run();
+        }
+    } else {
+        llvm_filecheck().stdin(&dump).patterns(checks).run();
+    }
+    if !["rust_plus_one_global_asm", "cmake_plus_one_c_global_asm", "cmake_plus_one_cxx_global_asm"]
+        .contains(&func_re)
+    {
+        // The assembler cannot avoid explicit `ret` instructions. Sequences
+        // of `shlq $0x0, (%rsp); lfence; retq` are used instead.
+        llvm_filecheck().args(&["--implicit-check-not", "ret"]).stdin(dump).patterns(checks).run();
+    }
+}