[dim] Emit error when calling abstract methods (#15433)

* Emitting bad image exception when a non virtual call is calling an abstract method.

* Fixing side-effect.
Implementing the same thing on interpreter.
Adding unit test.

mono/metadata/jit-icall-reg.h

@@ -302,6 +302,7 @@ MONO_JIT_ICALL (mono_threads_exit_gc_unsafe_region_unbalanced) \
 MONO_JIT_ICALL (mono_threads_state_poll) \
 MONO_JIT_ICALL (mono_throw_exception) \
 MONO_JIT_ICALL (mono_throw_method_access) \
+MONO_JIT_ICALL (mono_throw_bad_image) \
 MONO_JIT_ICALL (mono_trace_enter_method) \
 MONO_JIT_ICALL (mono_trace_leave_method) \
 MONO_JIT_ICALL (mono_upgrade_remote_class_wrapper) \

mono/mini/interp/transform.c

@@ -882,6 +882,15 @@ interp_generate_mae_throw (TransformData *td, MonoMethod *method, MonoMethod *ta
 	td->sp -= 2;
 }
 
+static void
+interp_generate_bie_throw (TransformData *td)
+{
+	MonoJitICallInfo *info = &mono_get_jit_icall_info ()->mono_throw_bad_image;
+
+	interp_add_ins (td, MINT_ICALL_PP_V);
+	td->last_ins->data [0] = get_data_item_index (td, (gpointer)info->func);
+}
+
 /*
  * These are additional locals that can be allocated as we transform the code.
  * They are allocated past the method locals so they are accessed in the same
@@ -1950,9 +1959,12 @@ interp_transform_call (TransformData *td, MonoMethod *method, MonoMethod *target
 	if (target_method)
 		mono_class_init_internal (target_method->klass);
 
-	if (!is_virtual && target_method && (target_method->flags & METHOD_ATTRIBUTE_ABSTRACT))
-		/* MS.NET seems to silently convert this to a callvirt */
-		is_virtual = TRUE;
+	if (!is_virtual && target_method && (target_method->flags & METHOD_ATTRIBUTE_ABSTRACT)) {
+		if (!mono_class_is_interface (method->klass))
+			interp_generate_bie_throw (td);
+		else
+			is_virtual = TRUE;
+	}
 
 	if (is_virtual && target_method && (!(target_method->flags & METHOD_ATTRIBUTE_VIRTUAL) ||
 		(MONO_METHOD_IS_FINAL (target_method) &&

mono/mini/jit-icalls.c

@@ -1522,6 +1522,14 @@ mono_throw_method_access (MonoMethod *caller, MonoMethod *callee)
 	g_free (caller_name);
 }
 
+void
+mono_throw_bad_image ()
+{
+	ERROR_DECL (error);
+	mono_error_set_generic_error (error, "System", "BadImageFormatException", "Bad IL format.");
+	mono_error_set_pending_exception (error);
+}
+
 void
 mono_dummy_jit_icall (void)
 {

mono/mini/jit-icalls.h

@@ -219,6 +219,8 @@ G_EXTERN_C double mono_ckfinite (double d);
 
 G_EXTERN_C void mono_throw_method_access (MonoMethod *caller, MonoMethod *callee);
 
+G_EXTERN_C void mono_throw_bad_image (void);
+
 G_EXTERN_C void mono_dummy_jit_icall (void);
 
 #endif /* __MONO_JIT_ICALLS_H__ */

mono/mini/method-to-ir.c

@@ -2244,6 +2244,12 @@ emit_method_access_failure (MonoCompile *cfg, MonoMethod *caller, MonoMethod *ca
 	mono_emit_jit_icall (cfg, mono_throw_method_access, args);
 }
 
+static void
+emit_bad_image_failure (MonoCompile *cfg, MonoMethod *caller, MonoMethod *callee)
+{
+	mono_emit_jit_icall (cfg, mono_throw_bad_image, NULL);
+}
+
 static MonoMethod*
 get_method_nofail (MonoClass *klass, const char *method_name, int num_params, int flags)
 {
@@ -7038,9 +7044,12 @@ mono_method_to_ir (MonoCompile *cfg, MonoMethod *method, MonoBasicBlock *start_b
 			if (mono_security_core_clr_enabled ())
 				ensure_method_is_allowed_to_call_method (cfg, method, cil_method);
 
-			if (!virtual_ && (cmethod->flags & METHOD_ATTRIBUTE_ABSTRACT))
-				/* MS.NET seems to silently convert this to a callvirt */
-				virtual_ = TRUE;
+			if (!virtual_ && (cmethod->flags & METHOD_ATTRIBUTE_ABSTRACT)) {
+				if (!mono_class_is_interface (method->klass))
+					emit_bad_image_failure (cfg, method, cil_method);
+				else
+					virtual_ = TRUE;
+			}
 
 			{
 				/*
@@ -7811,7 +7820,6 @@ mono_method_to_ir (MonoCompile *cfg, MonoMethod *method, MonoBasicBlock *start_b
 				}
 				emit_seq_point (cfg, method, next_ip, FALSE, TRUE);
 			}
-
 			break;
 		}
 		case MONO_CEE_RET:

mono/mini/mini-runtime.c

@@ -4628,6 +4628,7 @@ register_icalls (void)
 	register_icall (mono_get_assembly_object, mono_icall_sig_object_ptr, TRUE);
 	register_icall (mono_get_method_object, mono_icall_sig_object_ptr, TRUE);
 	register_icall (mono_throw_method_access, mono_icall_sig_void_ptr_ptr, FALSE);
+	register_icall (mono_throw_bad_image, mono_icall_sig_void, FALSE);
 	register_icall_no_wrapper (mono_dummy_jit_icall, mono_icall_sig_void);
 
 	register_icall_with_wrapper (mono_monitor_enter_internal, mono_icall_sig_int32_obj);

mono/tests/Makefile.am

@@ -1011,6 +1011,7 @@ TESTS_IL_SRC=			\
 	dim-protected-accessibility2.il \
 	dim-reabstraction.il \
 	dim-reabstraction-generics.il \
+	dim-abstractcall.il \
 	twopassvariance.il \
 	tailcall-generic-cast-conservestack-il.il \
 	tailcall-generic-cast-nocrash-il.il \

mono/tests/dim-abstractcall.il

@@ -0,0 +1,115 @@
+
+//  Microsoft (R) .NET Framework IL Disassembler.  Version 4.6.1055.0
+//  Copyright (c) Microsoft Corporation.  All rights reserved.
+
+
+
+// Metadata version: v4.0.30319.assembly extern mscorlib { }
+.assembly abstractcalls { }
+
+.class interface public abstract auto ansi I1
+{
+  .method public hidebysig newslot virtual abstract
+          instance int32 Add(int32 x) cil managed
+  {
+  }
+}
+
+.class public abstract auto ansi C1
+  extends [mscorlib]System.Object
+  implements I1
+{
+  .method public hidebysig specialname rtspecialname 
+          instance void .ctor() cil managed
+  {
+    ldarg.0
+    call instance void [mscorlib]System.Object::.ctor()
+    ret
+  }
+
+  .method public hidebysig newslot virtual abstract
+          instance int32 Remove(int32 x) cil managed
+  {
+  }
+}
+
+.class public auto ansi C2
+  extends [mscorlib]System.Object
+  implements I1
+{
+  .method public hidebysig specialname rtspecialname 
+          instance void .ctor() cil managed
+  {
+    ldarg.0
+    call instance void C1::.ctor()
+    ret
+  }
+
+  .method public hidebysig virtual
+          instance int32 Remove(int32 x) cil managed
+  {
+    ldc.i4.0
+    ret
+  }
+
+  .method public hidebysig newslot virtual
+          instance int32 Add(int32 x) cil managed
+   {
+    ldc.i4.5
+    ret
+  }
+}
+
+.method private hidebysig static void CallClass() cil managed
+{
+  newobj instance void C2::.ctor()
+  ldc.i4.0
+  call instance int32 C1::Remove(int32)
+  pop
+  ret
+}
+
+.method private hidebysig static void CallInterface() cil managed
+{
+  newobj instance void C2::.ctor()
+  ldc.i4.0
+  call instance int32 I1::Add(int32)
+  pop
+  ret
+}
+
+.method private hidebysig static int32 Main() cil managed
+{
+  .entrypoint
+
+  .try
+  {
+    call void CallClass()
+    leave Fail
+  }
+  catch [System.Runtime]System.BadImageFormatException
+  {
+      leave AbstractClassOK
+  }
+
+AbstractClassOK:
+
+  .try
+  {
+    call void CallInterface()
+    leave Fail
+  }
+  catch [System.Runtime]System.BadImageFormatException
+  {
+    leave AbstractInterfaceOK
+  }
+
+AbstractInterfaceOK:
+  ldc.i4 0
+  ret
+
+Fail:
+	ldc.i4 155
+    ret
+}
+