From a891f907f199fd203c1cfddd1b55a45cc2158460 Mon Sep 17 00:00:00 2001
From: _xeroxz <xerox@back.engineer>
Date: Mon, 15 Feb 2021 01:28:25 -0800
Subject: [PATCH] added div error ISR...

---
 drv_entry.cpp    | 1 +
 idt.hpp          | 1 +
 idt_handlers.asm | 2 ++
 vmcs.cpp         | 2 --
 vmxlaunch.cpp    | 4 ++++
 5 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drv_entry.cpp b/drv_entry.cpp
index b5e1039..e91989e 100644
--- a/drv_entry.cpp
+++ b/drv_entry.cpp
@@ -49,6 +49,7 @@ auto drv_entry(PDRIVER_OBJECT driver_object, PUNICODE_STRING registry_path) -> N
 	// change gp, pf, and de to vmxroot handlers...
 	idt::table[general_protection] = idt::create_entry(hv::idt_addr_t{ __gp_handler }, idt::ist_idx::gp);
 	idt::table[page_fault] = idt::create_entry(hv::idt_addr_t{ __pf_handler }, idt::ist_idx::pf);
+	idt::table[divide_error] = idt::create_entry(hv::idt_addr_t{ __de_handler }, idt::ist_idx::de);
 
 	// used for SEH in vmxroot fault handler...
 	idt::image_base = driver_object->DriverStart;
diff --git a/idt.hpp b/idt.hpp
index bfab4af..8b60ac1 100644
--- a/idt.hpp
+++ b/idt.hpp
@@ -6,6 +6,7 @@
 #pragma section(".idt", read, write)
 extern "C" void __gp_handler(void);
 extern "C" void __pf_handler(void);
+extern "C" void __de_handler(void);
 extern "C" void seh_handler(hv::pidt_regs_t regs);
 
 namespace idt
diff --git a/idt_handlers.asm b/idt_handlers.asm
index d9e86d6..8c5079e 100644
--- a/idt_handlers.asm
+++ b/idt_handlers.asm
@@ -1,6 +1,7 @@
 extern seh_handler : proc
 
 .code
+__de_handler proc
 __pf_handler proc
 __gp_handler proc
 	push rax
@@ -80,4 +81,5 @@ __gp_handler proc
 	iretq
 __gp_handler endp
 __pf_handler endp
+__de_handler endp
 end
\ No newline at end of file
diff --git a/vmcs.cpp b/vmcs.cpp
index 39755cf..6bc8697 100644
--- a/vmcs.cpp
+++ b/vmcs.cpp
@@ -50,8 +50,6 @@ namespace vmcs
 		tr.request_privilege_level = NULL;
 		tr.table = NULL;
 		__vmx_vmwrite(VMCS_HOST_TR_SELECTOR, tr.flags);
-
-
 	}
 
 	auto setup_guest() -> void
diff --git a/vmxlaunch.cpp b/vmxlaunch.cpp
index 873a42c..52f22f3 100644
--- a/vmxlaunch.cpp
+++ b/vmxlaunch.cpp
@@ -29,6 +29,10 @@ auto vmxlaunch::init_vmcs(cr3 cr3_value) -> void
 		reinterpret_cast<u64>(ExAllocatePool(NonPagedPool,
 			PAGE_SIZE * HOST_STACK_PAGES)) + (PAGE_SIZE * HOST_STACK_PAGES);
 
+	vcpu->tss.interrupt_stack_table[idt::ist_idx::de] =
+		reinterpret_cast<u64>(ExAllocatePool(NonPagedPool,
+			PAGE_SIZE * HOST_STACK_PAGES)) + (PAGE_SIZE * HOST_STACK_PAGES);
+
 	vcpu->gdt[segment_selector{ readtr() }.idx].base_address_upper = tss.upper;
 	vcpu->gdt[segment_selector{ readtr() }.idx].base_address_high = tss.high;
 	vcpu->gdt[segment_selector{ readtr() }.idx].base_address_middle = tss.middle;