FnAbi checks

Author: geetanshjuneja

rust-version

@@ -1 +1 @@
-54a0f387ea8c7bcb79b8e40c074a484d31b51990
+8c07d140e00dfa5b0988754051d07d8a91ff01f7

src/helpers.rs

@@ -14,7 +14,7 @@ use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::middle::dependency_format::Linkage;
 use rustc_middle::middle::exported_symbols::ExportedSymbol;
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf, MaybeResult, TyAndLayout};
-use rustc_middle::ty::{self, FloatTy, IntTy, Ty, TyCtxt, UintTy};
+use rustc_middle::ty::{self, Binder, FloatTy, FnSig, IntTy, Ty, TyCtxt, UintTy};
 use rustc_session::config::CrateType;
 use rustc_span::{Span, Symbol};
 use rustc_target::callconv::{Conv, FnAbi};
@@ -1187,6 +1187,58 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         interp_ok(array)
     }
+
+    fn check_fn_abi(
+        &mut self,
+        input_args: &[Ty<'tcx>],
+        output_ty: Ty<'tcx>,
+        safety: Safety,
+        abi: ExternAbi,
+        fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
+    ) -> InterpResult<'tcx, ()> {
+        let this = self.eval_context_mut();
+        let mut inputs_and_output = input_args.to_vec();
+        inputs_and_output.push(output_ty);
+        let fn_sig_binder = Binder::dummy(FnSig {
+            inputs_and_output: this.machine.tcx.mk_type_list(&inputs_and_output),
+            c_variadic: false,
+            safety,
+            abi,
+        });
+        let exp_fn_abi = this.fn_abi_of_fn_ptr(fn_sig_binder, Default::default())?;
+        if !self.check_abi_compat(fn_abi, exp_fn_abi)? {
+            throw_ub_format!("Invalid argument type: ABI mismatch");
+        }
+        interp_ok(())
+    }
+
+    // Check where two FnAbi's are compatible
+    fn check_abi_compat(
+        &mut self,
+        caller_fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
+        callee_fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
+    ) -> InterpResult<'tcx, bool> {
+        let this = self.eval_context_mut();
+        let caller_args_abi = &caller_fn_abi.args;
+        let callee_args_abi = &callee_fn_abi.args;
+
+        if caller_fn_abi.c_variadic != callee_fn_abi.c_variadic
+            || callee_fn_abi.fixed_count != caller_fn_abi.fixed_count
+            || callee_fn_abi.can_unwind != caller_fn_abi.can_unwind
+            || !this.check_argument_compat(&caller_fn_abi.ret, &callee_fn_abi.ret)?
+            || !caller_args_abi
+                .iter()
+                .zip(callee_args_abi.iter())
+                .map(|(caller_arg, callee_arg)| this.check_argument_compat(caller_arg, callee_arg))
+                .collect::<InterpResult<'tcx, Vec<bool>>>()?
+                .into_iter()
+                .all(|b| b)
+        {
+            return interp_ok(false);
+        }
+
+        interp_ok(true)
+    }
 }
 
 impl<'tcx> MiriMachine<'tcx> {

src/shims/unix/foreign_items.rs

@@ -1,7 +1,8 @@
 use std::ffi::OsStr;
 use std::str;
 
-use rustc_abi::Size;
+use rustc_abi::{ExternAbi, Size};
+use rustc_hir::Safety;
 use rustc_middle::ty::Ty;
 use rustc_middle::ty::layout::LayoutOf;
 use rustc_span::Symbol;
@@ -200,6 +201,13 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 this.write(fd, buf, count, Some(offset), dest)?;
             }
             "close" => {
+                this.check_fn_abi(
+                    &[this.machine.layouts.i32.ty],
+                    this.machine.layouts.i32.ty,
+                    Safety::Unsafe,
+                    ExternAbi::C { unwind: false },
+                    abi,
+                )?;
                 let [fd] = this.check_shim(abi, Conv::C, link_name, args)?;
                 let result = this.close(fd)?;
                 this.write_scalar(result, dest)?;