From 522d74b65d5fb7ae051acfd49bd9248f1ef0c11a Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Thu, 29 Sep 2022 19:30:42 +0200
Subject: [PATCH] Add is_user_address and is_kernel_address functions

---
 kernel/include/memory/Memory.h   |  3 +++
 kernel/src/memory/Memory.cpp     | 10 ++++++++++
 kernel/src/trace/StackTracer.cpp | 10 ++++++++--
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/kernel/include/memory/Memory.h b/kernel/include/memory/Memory.h
index e7663dcd..aa5aebf3 100644
--- a/kernel/include/memory/Memory.h
+++ b/kernel/include/memory/Memory.h
@@ -5,4 +5,7 @@ namespace Memory
 {
     uint64_t get_system();
     uint64_t get_usable();
+
+    bool is_user_address(uintptr_t address);
+    bool is_kernel_address(uintptr_t address);
 }
\ No newline at end of file
diff --git a/kernel/src/memory/Memory.cpp b/kernel/src/memory/Memory.cpp
index 81e8b046..705ed483 100644
--- a/kernel/src/memory/Memory.cpp
+++ b/kernel/src/memory/Memory.cpp
@@ -41,4 +41,14 @@ uint64_t Memory::get_usable()
     cached = true;
 
     return result;
+}
+
+bool Memory::is_kernel_address(uintptr_t address)
+{
+    return address > 0xfffffffff8000000;
+}
+
+bool Memory::is_user_address(uintptr_t address)
+{
+    return address && address < 0xfffffffff8000000;
 }
\ No newline at end of file
diff --git a/kernel/src/trace/StackTracer.cpp b/kernel/src/trace/StackTracer.cpp
index 18d1fe9b..58cdbeeb 100644
--- a/kernel/src/trace/StackTracer.cpp
+++ b/kernel/src/trace/StackTracer.cpp
@@ -1,4 +1,5 @@
 #include "trace/StackTracer.h"
+#include "memory/Memory.h"
 #include "std/stdio.h"
 #include "trace/Resolve.h"
 
@@ -20,7 +21,7 @@ typedef struct stackframe
 void StackTracer::trace()
 {
     stackframe* frame = (stackframe*)m_base_pointer;
-    while (frame && (uint64_t)frame > 0xfffffffff8000000)
+    while (Memory::is_kernel_address((uintptr_t)frame))
     {
         char symbol_name[512];
         get_symbol_name(frame->instruction, symbol_name);
@@ -31,6 +32,11 @@ void StackTracer::trace()
 
 void StackTracer::trace_with_ip(uintptr_t ip)
 {
+    if (!Memory::is_kernel_address(ip))
+    {
+        printf("(user stack)");
+        return;
+    }
     char symbol_name[512];
     get_symbol_name(ip, symbol_name);
     printf("%lx: %s\n", ip, symbol_name);
@@ -42,7 +48,7 @@ bool stack_trace_contains(uintptr_t address)
     uintptr_t base_pointer;
     asm volatile("mov %%rbp, %0" : "=r"(base_pointer));
     stackframe* frame = (stackframe*)base_pointer;
-    while (frame && (uint64_t)frame > 0xfffffffff8000000)
+    while (Memory::is_kernel_address((uintptr_t)frame))
     {
         if (frame->instruction == address) return true;
         frame = frame->next;