go_env hook: use a different stack for the hook execution (#309)

* go_env hook: use a different stack for the hook execution

CHANGELOG.md

@@ -7,6 +7,12 @@ Check [Keep a Changelog](http://keepachangelog.com/) for recommendations on how
 
 ## [Unreleased]
 
+### Fixed
+- mirrord-layer: Go environment variables crash - run Go env setup in a different stack (should fix [#292](https://github.com/metalbear-co/mirrord/issues/292))
+
+### Changed
+- mirrord-layer: Add `#![feature(let_chains)]` to `lib.rs` to support new compiler version.
+
 ## 2.10.1
 ### Fixed
 - CI:Release - Fix typo that broke the build

mirrord-layer/Cargo.toml

@@ -42,6 +42,7 @@ regex = "1"
 errno = "0.2"
 async-trait = "0.1"
 socket2 = "0.4"
+stacker = "0.1"
 
 [lib]
 crate_type = ["cdylib"]

mirrord-layer/src/go_env.rs

@@ -40,14 +40,16 @@ fn make_argv() -> Vec<*mut c_char> {
 
 #[hook_fn]
 unsafe extern "C" fn goenvs_unix_detour() {
-    trace!("hook goenvs_unix");
-    let modules = frida_gum::Module::enumerate_modules();
-    let binary = &modules.first().unwrap().name;
-    if let Some(argv) = frida_gum::Module::find_symbol_by_name(binary, "runtime.argv") {
-        let mut new_argv = ManuallyDrop::new(make_argv());
-        let argv_ptr: *mut *mut *mut i8 = argv.0.cast();
-        std::ptr::replace(argv_ptr, new_argv.as_mut_ptr());
-    }
+    stacker::grow(32 * 1024 * 1024, || {
+        trace!("hook goenvs_unix");
+        let modules = frida_gum::Module::enumerate_modules();
+        let binary = &modules.first().unwrap().name;
+        if let Some(argv) = frida_gum::Module::find_symbol_by_name(binary, "runtime.argv") {
+            let mut new_argv = ManuallyDrop::new(make_argv());
+            let argv_ptr: *mut *mut *mut i8 = argv.0.cast();
+            std::ptr::replace(argv_ptr, new_argv.as_mut_ptr());
+        }
+    });
     FN_GOENVS_UNIX();
 }
 

mirrord-layer/src/lib.rs

@@ -5,6 +5,7 @@
 #![feature(naked_functions)]
 #![feature(result_flattening)]
 #![feature(io_error_uncategorized)]
+#![feature(let_chains)]
 
 use std::{
     collections::{HashSet, VecDeque},