From 18ad55be0ba2c418c766c9857075b3b64d28104e Mon Sep 17 00:00:00 2001 From: liamwhite Date: Fri, 25 Aug 2023 17:59:32 -0400 Subject: kernel: offset code entry point for 39-bit address space type (#11326) --- src/core/hle/kernel/k_process.cpp | 25 ++++++++++++++++++++----- src/core/hle/kernel/k_process.h | 7 +++++++ 2 files changed, 27 insertions(+), 5 deletions(-) (limited to 'src/core/hle/kernel') diff --git a/src/core/hle/kernel/k_process.cpp b/src/core/hle/kernel/k_process.cpp index e573e2a57..703049ede 100644 --- a/src/core/hle/kernel/k_process.cpp +++ b/src/core/hle/kernel/k_process.cpp @@ -38,7 +38,7 @@ namespace { */ void SetupMainThread(Core::System& system, KProcess& owner_process, u32 priority, KProcessAddress stack_top) { - const KProcessAddress entry_point = owner_process.GetPageTable().GetCodeRegionStart(); + const KProcessAddress entry_point = owner_process.GetEntryPoint(); ASSERT(owner_process.GetResourceLimit()->Reserve(LimitableResource::ThreadCountMax, 1)); KThread* thread = KThread::Create(system.Kernel()); @@ -358,6 +358,21 @@ Result KProcess::LoadFromMetadata(const FileSys::ProgramMetadata& metadata, std: m_system_resource_size = metadata.GetSystemResourceSize(); m_image_size = code_size; + if (metadata.GetAddressSpaceType() == FileSys::ProgramAddressSpaceType::Is39Bit) { + // For 39-bit processes, the ASLR region starts at 0x800'0000 and is ~512GiB large. + // However, some (buggy) programs/libraries like skyline incorrectly depend on the + // existence of ASLR pages before the entry point, so we will adjust the load address + // to point to about 2GiB into the ASLR region. + m_code_address = 0x8000'0000; + } else { + // All other processes can be mapped at the beginning of the code region. + if (metadata.GetAddressSpaceType() == FileSys::ProgramAddressSpaceType::Is36Bit) { + m_code_address = 0x800'0000; + } else { + m_code_address = 0x20'0000; + } + } + KScopedResourceReservation memory_reservation( m_resource_limit, LimitableResource::PhysicalMemoryMax, code_size + m_system_resource_size); if (!memory_reservation.Succeeded()) { @@ -368,15 +383,15 @@ Result KProcess::LoadFromMetadata(const FileSys::ProgramMetadata& metadata, std: // Initialize process address space if (const Result result{m_page_table.InitializeForProcess( metadata.GetAddressSpaceType(), false, false, false, KMemoryManager::Pool::Application, - 0x8000000, code_size, std::addressof(m_kernel.GetAppSystemResource()), m_resource_limit, - m_kernel.System().ApplicationMemory())}; + this->GetEntryPoint(), code_size, std::addressof(m_kernel.GetAppSystemResource()), + m_resource_limit, m_kernel.System().ApplicationMemory())}; result.IsError()) { R_RETURN(result); } // Map process code region - if (const Result result{m_page_table.MapProcessCode(m_page_table.GetCodeRegionStart(), - code_size / PageSize, KMemoryState::Code, + if (const Result result{m_page_table.MapProcessCode(this->GetEntryPoint(), code_size / PageSize, + KMemoryState::Code, KMemoryPermission::None)}; result.IsError()) { R_RETURN(result); diff --git a/src/core/hle/kernel/k_process.h b/src/core/hle/kernel/k_process.h index c9b37e138..4fdeaf11a 100644 --- a/src/core/hle/kernel/k_process.h +++ b/src/core/hle/kernel/k_process.h @@ -177,6 +177,10 @@ public: return m_program_id; } + KProcessAddress GetEntryPoint() const { + return m_code_address; + } + /// Gets the resource limit descriptor for this process KResourceLimit* GetResourceLimit() const; @@ -485,6 +489,9 @@ private: /// Address indicating the location of the process' dedicated TLS region. KProcessAddress m_plr_address = 0; + /// Address indicating the location of the process's entry point. + KProcessAddress m_code_address = 0; + /// Random values for svcGetInfo RandomEntropy std::array m_random_entropy{}; -- cgit v1.2.3