[core/loader] Implement a bit improper ASLR (#2945)

A bit improper of an ASLR - it does something but something good? Who knows...
All I know is that there is a non-uniform distrobution for rand() and that rng_seed is likely a better solution?
I don't know

Signed-off-by: lizzie lizzie@eden-emu.dev

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/2945
Reviewed-by: Maufeat <sahyno1996@gmail.com>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Co-authored-by: lizzie <lizzie@eden-emu.dev>
Co-committed-by: lizzie <lizzie@eden-emu.dev>
This commit is contained in:
lizzie 2025-11-04 22:35:34 +01:00 committed by crueter
parent 6abaee94a6
commit 504df4856d
No known key found for this signature in database
GPG key ID: 425ACD2D4830EBC6
5 changed files with 34 additions and 19 deletions

View file

@ -5,6 +5,7 @@
// SPDX-License-Identifier: GPL-2.0-or-later
#include <cstring>
#include "common/settings.h"
#include "core/file_sys/kernel_executable.h"
#include "core/file_sys/program_metadata.h"
#include "core/hle/kernel/code_set.h"
@ -76,11 +77,10 @@ AppLoader::LoadResult AppLoader_KIP::Load(Kernel::KProcess& process,
Kernel::CodeSet codeset;
Kernel::PhysicalMemory program_image;
const auto load_segment = [&program_image](Kernel::CodeSet::Segment& segment,
const std::vector<u8>& data, u32 offset) {
const auto load_segment = [&program_image](Kernel::CodeSet::Segment& segment, const std::vector<u8>& data, u32 offset) {
segment.addr = offset;
segment.offset = offset;
segment.size = PageAlignSize(static_cast<u32>(data.size()));
segment.size = PageAlignSize(u32(data.size()));
program_image.resize(offset + data.size());
std::memcpy(program_image.data() + offset, data.data(), data.size());
};
@ -92,10 +92,14 @@ AppLoader::LoadResult AppLoader_KIP::Load(Kernel::KProcess& process,
program_image.resize(PageAlignSize(kip->GetBSSOffset()) + kip->GetBSSSize());
codeset.DataSegment().size += kip->GetBSSSize();
// TODO: this is bad form of ASLR, it sucks
size_t aslr_offset = ((::Settings::values.rng_seed_enabled.GetValue()
? ::Settings::values.rng_seed.GetValue()
: std::rand()) * 0x734287f27) & 0xfff000;
// Setup the process code layout
if (process
.LoadFromMetadata(FileSys::ProgramMetadata::GetDefault(), program_image.size(), 0,
false)
.LoadFromMetadata(FileSys::ProgramMetadata::GetDefault(), program_image.size(), 0, aslr_offset, false)
.IsError()) {
return {ResultStatus::ErrorNotInitialized, {}};
}