kasan.cpp File Reference

Implementation of the Kernel Address Sanitizer (KASan) handler. More...

#include <runtime/kasan.h>
#include <common/logger.h>

Go to the source code of this file.

Functions
void	__asan_load1_noabort (uintptr_t address)
	Triggered when a memory load access violation of 1 byte is detected.
void	__asan_load2_noabort (uintptr_t address)
	Triggered when a memory load access violation of 2 bytes is detected.
void	__asan_load4_noabort (uintptr_t address)
	Triggered when a memory load access violation of 4 bytes is detected.
void	__asan_load8_noabort (uintptr_t address)
	Triggered when a memory load access violation of 8 bytes is detected.
void	__asan_load16_noabort (uintptr_t address)
	Triggered when a memory load access violation of 16 bytes is detected.
void	__asan_loadN_noabort (uintptr_t address, size_t size)
	Triggered when a memory load access violation of arbitrary size is detected.
void	__asan_store1_noabort (uintptr_t address)
	Triggered when a memory store access violation of 1 byte is detected.
void	__asan_store2_noabort (uintptr_t address)
	Triggered when a memory store access violation of 2 bytes is detected.
void	__asan_store4_noabort (uintptr_t address)
	Triggered when a memory store access violation of 4 bytes is detected.
void	__asan_store8_noabort (uintptr_t address)
	Triggered when a memory store access violation of 8 bytes is detected.
void	__asan_store16_noabort (uintptr_t address)
	Triggered when a memory store access violation of 16 bytes is detected.
void	__asan_storeN_noabort (uintptr_t address, size_t size)
	Triggered when a memory store access violation of arbitrary size is detected.
void	__asan_handle_no_return ()
	Triggered when a function that is expected to not return does return.
void	__asan_alloca_poison (uintptr_t address, size_t size)
	Poisons a region of stack memory allocated with alloca.
void	__asan_alloca_unpoison (void *stack_top, void *stack_bottom)
	Unpoisons a region of stack memory allocated with alloca.
void	__asan_set_shadow_00 (void *pointer, size_t size)
	Unpoisons a region of memory, marking it as accessible.
void	__asan_set_shadow_f8 (void *pointer, size_t size)
	Poisons a region of memory, marking it as inaccessible.
void	__asan_before_dynamic_init (const void *module_name)
	Called before dynamic initialization of a module.
void	__asan_after_dynamic_init (const void *module_name)
	Called after dynamic initialization of a module.

Detailed Description

Implementation of the Kernel Address Sanitizer (KASan) handler.

Date

22nd November 2025

Author

Max Tyson

Definition in file kasan.cpp.

Function Documentation

__asan_after_dynamic_init()

void __asan_after_dynamic_init

(

const void *

module_name

)

Called after dynamic initialization of a module.

Parameters

module_name

The name of the module that was initialized

Definition at line 239 of file kasan.cpp.

                                                                    {
    // Nothing to do
 }

__asan_alloca_poison()

void __asan_alloca_poison	(	uintptr_t	address,
		size_t	size
	)

Poisons a region of stack memory allocated with alloca.

Parameters

address	The starting address of the allocated memory
size	The size of the allocated memory in bytes

Definition at line 181 of file kasan.cpp.

                                                                     {
    //TODO: Implement stack poisoning
    ASSERT(false, "KASAN ERROR: Stack poisoning not implemented for address 0x%lx of size %zu", address, size);
}

References ASSERT.

__asan_alloca_unpoison()

void __asan_alloca_unpoison	(	void *	stack_top,
		void *	stack_bottom
	)

Unpoisons a region of stack memory allocated with alloca.

Parameters

stack_top	The top address of the allocated memory
stack_bottom	The bottom address of the allocated memory

Definition at line 192 of file kasan.cpp.

                                                                            {
    //TODO: Implement stack unpoisoning
    ASSERT(false, "KASAN ERROR: Stack unpoisoning not implemented for range 0x%p - 0x%p", stack_bottom, stack_top);
}

References ASSERT.

__asan_before_dynamic_init()

void __asan_before_dynamic_init

(

const void *

module_name

)

Called before dynamic initialization of a module.

Parameters

module_name

The name of the module being initialized

Definition at line 230 of file kasan.cpp.

                                                                    {
    // Nothing to do
}

__asan_handle_no_return()

void __asan_handle_no_return

(

)

Triggered when a function that is expected to not return does return.

Definition at line 171 of file kasan.cpp.

                                          {
    ASSERT(false, "KASAN ERROR: Function marked 'noreturn' has returned");
}

References ASSERT.

__asan_load16_noabort()

void __asan_load16_noabort

(

uintptr_t

address

)

Triggered when a memory load access violation of 16 bytes is detected.

Parameters

address

The address that was accessed

Definition at line 99 of file kasan.cpp.

                                                         {
    KASanHandler::handle(false, address, 16, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_load1_noabort()

void __asan_load1_noabort

(

uintptr_t

address

)

Triggered when a memory load access violation of 1 byte is detected.

Parameters

address

The address that was accessed

Definition at line 63 of file kasan.cpp.

                                                        {
    KASanHandler::handle(false, address, 1, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_load2_noabort()

void __asan_load2_noabort

(

uintptr_t

address

)

Triggered when a memory load access violation of 2 bytes is detected.

Parameters

address

The address that was accessed

Definition at line 72 of file kasan.cpp.

                                                        {
    KASanHandler::handle(false, address, 2, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_load4_noabort()

void __asan_load4_noabort

(

uintptr_t

address

)

Triggered when a memory load access violation of 4 bytes is detected.

Parameters

address

The address that was accessed

Definition at line 81 of file kasan.cpp.

                                                        {
    KASanHandler::handle(false, address, 4, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_load8_noabort()

void __asan_load8_noabort

(

uintptr_t

address

)

Triggered when a memory load access violation of 8 bytes is detected.

Parameters

address

The address that was accessed

Definition at line 90 of file kasan.cpp.

                                                        {
    KASanHandler::handle(false, address, 8, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_loadN_noabort()

void __asan_loadN_noabort	(	uintptr_t	address,
		size_t	size
	)

Triggered when a memory load access violation of arbitrary size is detected.

Parameters

address	The address that was accessed
size	The size of the access in bytes

Definition at line 109 of file kasan.cpp.

                                                                     {
    KASanHandler::handle(false, address, size, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_set_shadow_00()

void __asan_set_shadow_00	(	void *	pointer,
		size_t	size
	)

Unpoisons a region of memory, marking it as accessible.

Parameters

pointer	The starting address of the memory
size	The size of the memory region in bytes

Definition at line 203 of file kasan.cpp.

                                                                 {
 
    // Clear the memory to mark it as unpoisoned
    for(int i = 0; i < size; ++i)
        ((int8_t*)pointer)[i] = 0;
 
}

__asan_set_shadow_f8()

void __asan_set_shadow_f8	(	void *	pointer,
		size_t	size
	)

Poisons a region of memory, marking it as inaccessible.

Parameters

pointer	The starting address of the memory
size	The size of the memory region in bytes

Definition at line 217 of file kasan.cpp.

                                                                {
 
    // Fill the memory to mark it as poisoned
    for(int i = 0; i < size; ++i)
        ((int8_t*)pointer)[i] = 0xF8;
 
}

__asan_store16_noabort()

void __asan_store16_noabort

(

uintptr_t

address

)

Triggered when a memory store access violation of 16 bytes is detected.

Parameters

address

The address that was accessed

Definition at line 154 of file kasan.cpp.

                                                          {
    KASanHandler::handle(true, address, 16, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_store1_noabort()

void __asan_store1_noabort

(

uintptr_t

address

)

Triggered when a memory store access violation of 1 byte is detected.

Parameters

address

The address that was accessed

Definition at line 118 of file kasan.cpp.

                                                         {
    KASanHandler::handle(true, address, 1, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_store2_noabort()

void __asan_store2_noabort

(

uintptr_t

address

)

Triggered when a memory store access violation of 2 bytes is detected.

Parameters

address

The address that was accessed

Definition at line 127 of file kasan.cpp.

                                                         {
    KASanHandler::handle(true, address, 2, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_store4_noabort()

void __asan_store4_noabort

(

uintptr_t

address

)

Triggered when a memory store access violation of 4 bytes is detected.

Parameters

address

The address that was accessed

Definition at line 136 of file kasan.cpp.

                                                         {
    KASanHandler::handle(true, address, 4, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_store8_noabort()

void __asan_store8_noabort

(

uintptr_t

address

)

Triggered when a memory store access violation of 8 bytes is detected.

Parameters

address

The address that was accessed

Definition at line 145 of file kasan.cpp.

                                                         {
    KASanHandler::handle(true, address, 8, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().

__asan_storeN_noabort()

void __asan_storeN_noabort	(	uintptr_t	address,
		size_t	size
	)

Triggered when a memory store access violation of arbitrary size is detected.

Parameters

address	The address that was accessed
size	The size of the access in bytes

Definition at line 164 of file kasan.cpp.

                                                                      {
    KASanHandler::handle(false, address, size, __builtin_return_address(0));
}

References MaxOS::runtime::KASanHandler::handle().