[mono] Fix crash in common_call_trampoline due to inconsistent rgctx mode (#57677)

* Assume MRGCTX mode if mini_method_is_default_method is true

* Fixes https://github.com/dotnet/runtime/issues/57664

Co-authored-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>

diff --git a/src/mono/mono/mini/mini-trampolines.c b/src/mono/mono/mini/mini-trampolines.c
index c6901fb339330d49853baeac83437ed31a8512c5..36fb6ca4d84b5c9b007a92700b6e059d704f1923 100644 (file)
--- a/src/mono/mono/mini/mini-trampolines.c
+++ b/src/mono/mono/mini/mini-trampolines.c
@@ -554,7 +554,7 @@ common_call_trampoline (host_mgreg_t *regs, guint8 *code, MonoMethod *m, MonoVTa
                /*
                 * The caller is gshared code, compute the actual method to call from M and this/rgctx.
                 */
-               if (m->is_inflated && mono_method_get_context (m)->method_inst) {
+               if (m->is_inflated && (mono_method_get_context (m)->method_inst || mini_method_is_default_method (m))) {
                        MonoMethodRuntimeGenericContext *mrgctx = (MonoMethodRuntimeGenericContext*)mono_arch_find_static_call_vtable (regs, code);
 
                        klass = mrgctx->class_vtable->klass;