Mono: Fix weird crash when loading corlib

This commit is contained in:
Ignacio Etcheverry 2018-08-22 00:33:23 +02:00
parent 5df91099c7
commit 143c471eff
2 changed files with 44 additions and 14 deletions

View File

@ -42,9 +42,15 @@
#include "gd_mono_class.h"
bool GDMonoAssembly::no_search = false;
bool GDMonoAssembly::in_preload = false;
Vector<String> GDMonoAssembly::search_dirs;
void GDMonoAssembly::assembly_load_hook(MonoAssembly *assembly, void *user_data) {
if (no_search)
return;
// If our search and preload hooks fail to load the assembly themselves, the mono runtime still might.
// Just do Assembly.LoadFrom("/Full/Path/On/Disk.dll");
// In this case, we wouldn't have the assembly known in GDMono, which causes crashes
@ -122,6 +128,8 @@ MonoAssembly *GDMonoAssembly::_search_hook(MonoAssemblyName *aname, void *user_d
return res ? res->get_assembly() : NULL;
}
static _THREAD_LOCAL_(MonoImage *) image_corlib_loading = NULL;
MonoAssembly *GDMonoAssembly::_preload_hook(MonoAssemblyName *aname, char **assemblies_path, void *user_data, bool refonly) {
(void)user_data; // UNUSED
@ -149,10 +157,27 @@ MonoAssembly *GDMonoAssembly::_preload_hook(MonoAssemblyName *aname, char **asse
}
}
{
// If we find the assembly here, we load it with `mono_assembly_load_from_full`,
// which in turn invokes load hooks before returning the MonoAssembly to us.
// One of the load hooks is `load_aot_module`. This hook can end up calling preload hooks
// again for the same assembly in certain in certain circumstances (the `do_load_image` part).
// If this is the case and we return NULL due to the no_search condition below,
// it will result in an internal crash later on. Therefore we need to return the assembly we didn't
// get yet from `mono_assembly_load_from_full`. Luckily we have the image, which already got it.
// This must be done here. If done in search hooks, it would cause `mono_assembly_load_from_full`
// to think another MonoAssembly for this assembly was already loaded, making it delete its own,
// when in fact both pointers were the same... This hooks thing is confusing.
if (image_corlib_loading) {
return mono_image_get_assembly(image_corlib_loading);
}
}
if (no_search)
return NULL;
no_search = true;
in_preload = true;
String name = mono_assembly_name_get_name(aname);
bool has_extension = name.ends_with(".dll");
@ -187,6 +212,7 @@ MonoAssembly *GDMonoAssembly::_preload_hook(MonoAssemblyName *aname, char **asse
}
no_search = false;
in_preload = false;
return res ? res->get_assembly() : NULL;
}
@ -209,23 +235,18 @@ GDMonoAssembly *GDMonoAssembly::_load_assembly_from(const String &p_name, const
}
void GDMonoAssembly::_wrap_mono_assembly(MonoAssembly *assembly) {
String p_name = mono_assembly_name_get_name(mono_assembly_get_name(assembly));
GDMonoAssembly **existingassembly = GDMono::get_singleton()->get_loaded_assembly(p_name);
if (no_search || existingassembly != NULL) {
// Not sure whether the existingassembly check matters
// since no_search handles it in most cases?
// Can't hurt.
return;
}
String name = mono_assembly_name_get_name(mono_assembly_get_name(assembly));
MonoImage *image = mono_assembly_get_image(assembly);
mono_image_addref(image);
GDMonoAssembly *gdassembly = memnew(GDMonoAssembly(p_name, mono_image_get_filename(image)));
gdassembly->assembly = assembly;
gdassembly->loaded = true;
gdassembly->image = image;
GDMonoAssembly *gdassembly = memnew(GDMonoAssembly(name, mono_image_get_filename(image)));
Error err = gdassembly->wrapper_for_image(image);
if (err != OK) {
memdelete(gdassembly);
ERR_FAIL();
}
MonoDomain *domain = mono_domain_get();
GDMono::get_singleton()->add_assembly(domain ? mono_domain_get_id(domain) : 0, gdassembly);
}
@ -280,8 +301,16 @@ no_pdb:
#endif
bool is_corlib_preload = in_preload && name == "mscorlib";
if (is_corlib_preload)
image_corlib_loading = image;
assembly = mono_assembly_load_from_full(image, image_filename.utf8().get_data(), &status, refonly);
if (is_corlib_preload)
image_corlib_loading = NULL;
ERR_FAIL_COND_V(status != MONO_IMAGE_OK || assembly == NULL, ERR_FILE_CANT_OPEN);
loaded = true;

View File

@ -89,6 +89,7 @@ class GDMonoAssembly {
#endif
static bool no_search;
static bool in_preload;
static Vector<String> search_dirs;
static void assembly_load_hook(MonoAssembly *assembly, void *user_data);