Kernel: Add a size argument to validate_read_from_kernel

Kernel/KSyms.cpp

@@ -104,12 +104,12 @@ static void load_ksyms_from_data(const ByteBuffer& buffer)
     RecognizedSymbol recognized_symbols[max_recognized_symbol_count];
     int recognized_symbol_count = 0;
     if (use_ksyms) {
-        for (u32* stack_ptr = (u32*)ebp; current->process().validate_read_from_kernel(VirtualAddress((u32)stack_ptr)) && recognized_symbol_count < max_recognized_symbol_count; stack_ptr = (u32*)*stack_ptr) {
+        for (u32* stack_ptr = (u32*)ebp; current->process().validate_read_from_kernel(VirtualAddress((u32)stack_ptr), sizeof(void*) * 2) && recognized_symbol_count < max_recognized_symbol_count; stack_ptr = (u32*)*stack_ptr) {
             u32 retaddr = stack_ptr[1];
             recognized_symbols[recognized_symbol_count++] = { retaddr, ksymbolicate(retaddr) };
         }
     } else {
-        for (u32* stack_ptr = (u32*)ebp; current->process().validate_read_from_kernel(VirtualAddress((u32)stack_ptr)); stack_ptr = (u32*)*stack_ptr) {
+        for (u32* stack_ptr = (u32*)ebp; current->process().validate_read_from_kernel(VirtualAddress((u32)stack_ptr), sizeof(void*) * 2); stack_ptr = (u32*)*stack_ptr) {
             u32 retaddr = stack_ptr[1];
             dbgprintf("%x (next: %x)\n", retaddr, stack_ptr ? (u32*)*stack_ptr : 0);
         }

Kernel/Process.cpp

@@ -1896,7 +1896,7 @@ static KernelMemoryCheckResult check_kernel_memory_access(VirtualAddress vaddr,
     return KernelMemoryCheckResult::NotInsideKernelMemory;
 }
 
-bool Process::validate_read_from_kernel(VirtualAddress vaddr) const
+bool Process::validate_read_from_kernel(VirtualAddress vaddr, ssize_t size) const
 {
     if (vaddr.is_null())
         return false;
@@ -1909,7 +1909,7 @@ bool Process::validate_read_from_kernel(VirtualAddress vaddr) const
         return false;
     if (is_kmalloc_address(vaddr.as_ptr()))
         return true;
-    return validate_read(vaddr.as_ptr(), 1);
+    return validate_read(vaddr.as_ptr(), size);
 }
 
 bool Process::validate_read_str(const char* str)

Kernel/Process.h

@@ -255,7 +255,7 @@ public:
     u32 m_ticks_in_user_for_dead_children { 0 };
     u32 m_ticks_in_kernel_for_dead_children { 0 };
 
-    bool validate_read_from_kernel(VirtualAddress) const;
+    bool validate_read_from_kernel(VirtualAddress, ssize_t) const;
 
     bool validate_read(const void*, ssize_t) const;
     bool validate_write(void*, ssize_t) const;

Kernel/Thread.cpp

@@ -708,7 +708,7 @@ String Thread::backtrace_impl() const
     StringBuilder builder;
     Vector<RecognizedSymbol, 64> recognized_symbols;
     recognized_symbols.append({ tss().eip, ksymbolicate(tss().eip) });
-    for (u32* stack_ptr = (u32*)frame_ptr(); process.validate_read_from_kernel(VirtualAddress((u32)stack_ptr)); stack_ptr = (u32*)*stack_ptr) {
+    for (u32* stack_ptr = (u32*)frame_ptr(); process.validate_read_from_kernel(VirtualAddress((u32)stack_ptr), sizeof(void*) * 2); stack_ptr = (u32*)*stack_ptr) {
         u32 retaddr = stack_ptr[1];
         recognized_symbols.append({ retaddr, ksymbolicate(retaddr) });
     }
@@ -738,7 +738,7 @@ Vector<u32> Thread::raw_backtrace(u32 ebp) const
     ProcessPagingScope paging_scope(process);
     Vector<u32> backtrace;
     backtrace.append(ebp);
-    for (u32* stack_ptr = (u32*)ebp; process.validate_read_from_kernel(VirtualAddress((u32)stack_ptr)); stack_ptr = (u32*)*stack_ptr) {
+    for (u32* stack_ptr = (u32*)ebp; process.validate_read_from_kernel(VirtualAddress((u32)stack_ptr), sizeof(void*) * 2); stack_ptr = (u32*)*stack_ptr) {
         u32 retaddr = stack_ptr[1];
         backtrace.append(retaddr);
     }