From e3c1a48104f58031b7680504791d1ada66f39dc0 Mon Sep 17 00:00:00 2001
From: mintsuki <mintsuki@protonmail.com>
Date: Fri, 12 Jul 2024 23:24:30 +0200
Subject: [PATCH] kern/misc: Ensure bootloader responses are not nil globally

---
 kernel/modules/acpi/acpi.v           |  3 +++
 kernel/modules/initramfs/initramfs.v |  4 ++++
 kernel/modules/memory/physical.v     | 10 ++++++----
 kernel/modules/memory/virtual.v      | 20 ++++++++++++++------
 kernel/modules/term/term.v           |  3 +++
 kernel/modules/time/time.v           |  6 +++++-
 kernel/modules/x86/smp/smp.v         |  3 +++
 7 files changed, 38 insertions(+), 11 deletions(-)

diff --git a/kernel/modules/acpi/acpi.v b/kernel/modules/acpi/acpi.v
index 99fbccfe0..65008aa3e 100644
--- a/kernel/modules/acpi/acpi.v
+++ b/kernel/modules/acpi/acpi.v
@@ -53,6 +53,9 @@ __global (
 )
 
 pub fn initialise() {
+	if rsdp_req.response == unsafe { nil } {
+		panic('acpi: ACPI not supported on this machine.')
+	}
 	rsdp_ptr := rsdp_req.response.address
 
 	if rsdp_ptr == 0 {
diff --git a/kernel/modules/initramfs/initramfs.v b/kernel/modules/initramfs/initramfs.v
index 9020d7035..e0e1c4702 100644
--- a/kernel/modules/initramfs/initramfs.v
+++ b/kernel/modules/initramfs/initramfs.v
@@ -59,6 +59,10 @@ __global (
 
 @[manualfree]
 pub fn initialise() {
+	if module_req.response == unsafe { nil } {
+		panic('Modules bootloader response missing')
+	}
+
 	if module_req.response.module_count < 1 {
 		panic('No initramfs')
 	}
diff --git a/kernel/modules/memory/physical.v b/kernel/modules/memory/physical.v
index 5d12d19e8..1dd21bfcf 100644
--- a/kernel/modules/memory/physical.v
+++ b/kernel/modules/memory/physical.v
@@ -24,10 +24,6 @@ __global (
 	volatile hhdm_req = limine.LimineHHDMRequest{
 		response: unsafe { nil }
 	}
-	volatile paging_mode_req = limine.LiminePagingModeRequest{
-		response: unsafe { nil }
-		mode: limine.limine_paging_mode_x86_64_5lvl
-	}
 )
 
 pub fn print_free() {
@@ -39,10 +35,16 @@ pub fn print_free() {
 }
 
 pub fn pmm_init() {
+	if hhdm_req.response == unsafe { nil } {
+		lib.kpanic(unsafe { nil }, c'HHDM bootloader response missing')
+	}
 	higher_half = hhdm_req.response.offset
 
 	C.printf(c'pmm: Higher half direct map at: %p\n', higher_half)
 
+	if memmap_req.response == unsafe { nil } {
+		lib.kpanic(unsafe { nil }, c'Memory map bootloader response missing')
+	}
 	memmap := memmap_req.response
 
 	unsafe {
diff --git a/kernel/modules/memory/virtual.v b/kernel/modules/memory/virtual.v
index 3a24728ae..6afd91f06 100644
--- a/kernel/modules/memory/virtual.v
+++ b/kernel/modules/memory/virtual.v
@@ -250,6 +250,10 @@ __global (
 	volatile memmap_req = limine.LimineMemmapRequest{
 		response: unsafe { nil }
 	}
+	volatile paging_mode_req = limine.LiminePagingModeRequest{
+		response: unsafe { nil }
+		mode: limine.limine_paging_mode_x86_64_5lvl
+	}
 )
 
 fn map_kernel_span(virt u64, phys u64, len u64, flags u64) {
@@ -265,14 +269,13 @@ fn map_kernel_span(virt u64, phys u64, len u64, flags u64) {
 }
 
 pub fn vmm_init() {
-	if paging_mode_req.response.mode == limine.limine_paging_mode_x86_64_5lvl {
-		print('vmm: Using 5 level paging\n')
-		la57 = true
+	if paging_mode_req.response != unsafe { nil } {
+		if paging_mode_req.response.mode == limine.limine_paging_mode_x86_64_5lvl {
+			print('vmm: Using 5 level paging\n')
+			la57 = true
+		}
 	}
 
-	print('vmm: Kernel physical base: 0x${kaddr_req.response.physical_base:x}\n')
-	print('vmm: Kernel virtual base: 0x${kaddr_req.response.virtual_base:x}\n')
-
 	kernel_pagemap.top_level = pmm_alloc(1)
 	if kernel_pagemap.top_level == 0 {
 		panic('vmm_init() allocation failure')
@@ -287,6 +290,11 @@ pub fn vmm_init() {
 	}
 
 	// Map kernel
+	if kaddr_req.response == unsafe { nil } {
+		panic('Kernel address bootloader response missing')
+	}
+	print('vmm: Kernel physical base: 0x${kaddr_req.response.physical_base:x}\n')
+	print('vmm: Kernel virtual base: 0x${kaddr_req.response.virtual_base:x}\n')
 	virtual_base := kaddr_req.response.virtual_base
 	physical_base := kaddr_req.response.physical_base
 
diff --git a/kernel/modules/term/term.v b/kernel/modules/term/term.v
index cd53efdae..e573342b6 100644
--- a/kernel/modules/term/term.v
+++ b/kernel/modules/term/term.v
@@ -31,6 +31,9 @@ __global (
 )
 
 pub fn initialise() {
+	if fb_req.response == unsafe { nil } {
+		panic('Framebuffer bootloader response missing')
+	}
 	framebuffer_tag = unsafe { fb_req.response.framebuffers[0] }
 	framebuffer_width = framebuffer_tag.width
 	framebuffer_height = framebuffer_tag.height
diff --git a/kernel/modules/time/time.v b/kernel/modules/time/time.v
index c30cafabf..b417d11ef 100644
--- a/kernel/modules/time/time.v
+++ b/kernel/modules/time/time.v
@@ -71,7 +71,11 @@ __global (
 )
 
 pub fn initialise() {
-	epoch := boottime_req.response.boot_time
+	epoch := if boottime_req.response != unsafe { nil } {
+		boottime_req.response.boot_time
+	} else {
+		0
+	}
 
 	monotonic_clock = TimeSpec{i64(epoch), 0}
 	realtime_clock = TimeSpec{i64(epoch), 0}
diff --git a/kernel/modules/x86/smp/smp.v b/kernel/modules/x86/smp/smp.v
index 5e7f7377a..99bb67689 100644
--- a/kernel/modules/x86/smp/smp.v
+++ b/kernel/modules/x86/smp/smp.v
@@ -25,6 +25,9 @@ __global (
 )
 
 pub fn initialise() {
+	if smp_req.response == unsafe { nil } {
+		panic('SMP bootloader response missing')
+	}
 	smp_tag := smp_req.response
 
 	println('smp: BSP LAPIC ID:    ${smp_tag.bsp_lapic_id:x}')