Atmosphere/libraries/libstratosphere/source/diag/impl/diag_backtrace_impl.os.horizon.cpp

218 lines
8.1 KiB
C++

/*
* Copyright (c) Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stratosphere.hpp>
namespace ams::diag::impl {
namespace {
uintptr_t GetAddressValue(uintptr_t address) {
if (address == 0) {
return 0;
}
if (!util::IsAligned(address, alignof(uintptr_t))) {
return 0;
}
return *reinterpret_cast<uintptr_t *>(address);
}
template<typename T, size_t N>
svc::MemoryInfo *GetMemoryInfoPointer(T (&arr)[N]) {
/* Check that there's enough space. */
static_assert(sizeof(T) * N <= sizeof(svc::MemoryInfo));
static_assert(alignof(T) >= alignof(svc::MemoryInfo));
return reinterpret_cast<svc::MemoryInfo *>(std::addressof(arr[0]));
}
bool IsValidLinkRegisterValue(uintptr_t lr, svc::MemoryInfo *info) {
/* Ensure the memory info is valid. */
Result query_res;
if (!(info->base_address <= lr && lr < info->base_address + info->size) && ({ svc::PageInfo page_info; query_res = svc::QueryMemory(info, std::addressof(page_info), lr); R_FAILED(query_res); })) {
AMS_SDK_LOG("Failed to get backtrace. Query memory failed. (lr: %p, result: %03d-%04d)\n", reinterpret_cast<void *>(lr), query_res.GetModule(), query_res.GetDescription());
return false;
}
/* Check that lr is valid. */
if (lr == 0) {
return false;
}
if (!util::IsAligned(lr, sizeof(u32))) {
AMS_SDK_LOG("Failed to get backtrace. The link register alignment is invalid. (lr: %p)\n", reinterpret_cast<void *>(lr));
return false;
}
/* Check that the lr points to code. */
if (info->permission != svc::MemoryPermission_ReadExecute) {
AMS_SDK_LOG("Failed to get backtrace. The link register points out of the code. (lr: %p)\n", reinterpret_cast<void *>(lr));
return false;
}
return true;
}
void GetNormalStackInfo(Backtrace::StackInfo *out) {
if (void * const fiber = nullptr /* TODO: os::GetCurrentFiber() */; fiber == nullptr) {
/* Get thread. */
auto * const thread = os::GetCurrentThread();
out->stack_top = reinterpret_cast<uintptr_t>(thread->stack);
out->stack_bottom = reinterpret_cast<uintptr_t>(thread->stack) + thread->stack_size;
} else {
/* TODO: Fiber. */
}
}
bool GetExceptionStackInfo(Backtrace::StackInfo *out, uintptr_t sp) {
/* Get the current stack info. */
uintptr_t cur_stack = 0;
size_t cur_stack_size = 0;
os::GetCurrentStackInfo(std::addressof(cur_stack), std::addressof(cur_stack_size));
/* Get the thread's stack info. */
uintptr_t thread_stack = 0;
size_t thread_stack_size = 0;
os::GetThreadStackInfo(std::addressof(thread_stack), std::addressof(thread_stack_size), os::GetCurrentThread());
/* If the current stack is the thread stack, exception stack isn't being used. */
if (cur_stack == thread_stack) {
AMS_ASSERT(cur_stack_size == thread_stack_size);
return false;
}
/* Check if the stack pointer is contained in the current stack. */
if (!(cur_stack <= sp && sp < cur_stack + cur_stack_size)) {
return false;
}
/* Set the output. */
out->stack_top = cur_stack;
out->stack_bottom = cur_stack + cur_stack_size;
return true;
}
}
NOINLINE void Backtrace::Initialize() {
/* Get the stack pointer/frame pointer. */
uintptr_t fp, sp;
__asm__ __volatile__(
#if defined(ATMOSPHERE_ARCH_ARM64)
"mov %[fp], fp\n"
"mov %[sp], sp\n"
#elif defined(ATMOSPHERE_ARCH_ARM)
"mov %[fp], x29\n"
"mov %[sp], sp\n"
#else
#error "Unknown architecture for Horizon fp/sp retrieval."
#endif
: [fp]"=&r"(fp), [sp]"=&r"(sp)
:
: "memory"
);
/* Set our stack info. */
this->SetStackInfo(fp, sp);
/* Step, to get our first lr. */
this->Step();
}
void Backtrace::Initialize(uintptr_t fp, uintptr_t sp, uintptr_t pc) {
/* Set our initial lr. */
m_lr = pc;
/* Set our stack info. */
this->SetStackInfo(fp, sp);
}
bool Backtrace::Step() {
/* We can't step without a frame pointer. */
if (m_fp == 0) {
if (m_current_stack_info != std::addressof(m_normal_stack_info)) {
AMS_SDK_LOG("Failed to get backtrace. The frame pointer is null.\n");
}
return false;
}
/* The frame pointer needs to be aligned. */
if (!util::IsAligned(m_fp, sizeof(uintptr_t))) {
AMS_SDK_LOG("Failed to get backtrace. The frame pointer alignment is invalid. (fp: %p)\n", reinterpret_cast<void *>(m_fp));
return false;
}
/* Ensure our current stack info is good. */
if (!(m_current_stack_info->stack_top <= m_fp && m_fp < m_current_stack_info->stack_bottom)) {
if (m_current_stack_info != std::addressof(m_exception_stack_info) || !(m_normal_stack_info.stack_top <= m_fp && m_fp < m_normal_stack_info.stack_bottom)) {
AMS_SDK_LOG("Failed to get backtrace. The frame pointer points out of the stack. (fp: %p, stack: %p-%p)\n", reinterpret_cast<void *>(m_fp), reinterpret_cast<void *>(m_current_stack_info->stack_top), reinterpret_cast<void *>(m_current_stack_info->stack_bottom));
return false;
}
m_current_stack_info = std::addressof(m_normal_stack_info);
} else if (m_fp <= m_prev_fp) {
AMS_SDK_LOG("Failed to get backtrace. The frame pointer is rewinding. (fp: %p, prev fp: %p, stack: %p-%p)\n", reinterpret_cast<void *>(m_fp), reinterpret_cast<void *>(m_prev_fp), reinterpret_cast<void *>(m_current_stack_info->stack_top), reinterpret_cast<void *>(m_current_stack_info->stack_bottom));
return false;
}
/* Update our previous fp. */
m_prev_fp = m_fp;
/* Read lr/fp. */
m_lr = GetAddressValue(m_fp + sizeof(m_fp));
m_fp = GetAddressValue(m_fp);
/* Check that lr is valid. */
if (IsValidLinkRegisterValue(m_lr, GetMemoryInfoPointer(m_memory_info_buffer))) {
return true;
} else {
m_lr = 0;
return false;
}
}
uintptr_t Backtrace::GetStackPointer() const {
if (m_fp != 0) {
return m_fp - sizeof(m_fp);
} else {
return m_current_stack_info->stack_bottom - sizeof(m_fp);
}
}
uintptr_t Backtrace::GetReturnAddress() const {
return m_lr;
}
void Backtrace::SetStackInfo(uintptr_t fp, uintptr_t sp) {
/* Get the normal stack info. */
GetNormalStackInfo(std::addressof(m_normal_stack_info));
/* Get the exception stack info. */
if (GetExceptionStackInfo(std::addressof(m_exception_stack_info), sp)) {
m_current_stack_info = std::addressof(m_exception_stack_info);
} else {
m_current_stack_info = std::addressof(m_normal_stack_info);
}
/* Set our frame pointer. */
m_fp = fp;
}
}