gdbstub: read module information from memory layout

This commit is contained in:
Liam 2023-11-11 10:41:06 -05:00
parent 40d4e9543b
commit 3b872b89d1
1 changed files with 118 additions and 47 deletions

View File

@ -562,6 +562,120 @@ static std::string PaginateBuffer(std::string_view buffer, std::string_view requ
}
}
static VAddr GetModuleEnd(Kernel::KProcessPageTable& page_table, VAddr base) {
Kernel::KMemoryInfo mem_info;
Kernel::Svc::MemoryInfo svc_mem_info;
Kernel::Svc::PageInfo page_info;
VAddr cur_addr{base};
// Expect: r-x Code (.text)
R_ASSERT(page_table.QueryInfo(std::addressof(mem_info), std::addressof(page_info), cur_addr));
svc_mem_info = mem_info.GetSvcMemoryInfo();
cur_addr = svc_mem_info.base_address + svc_mem_info.size;
if (svc_mem_info.state != Kernel::Svc::MemoryState::Code ||
svc_mem_info.permission != Kernel::Svc::MemoryPermission::ReadExecute) {
return cur_addr - 1;
}
// Expect: r-- Code (.rodata)
R_ASSERT(page_table.QueryInfo(std::addressof(mem_info), std::addressof(page_info), cur_addr));
svc_mem_info = mem_info.GetSvcMemoryInfo();
cur_addr = svc_mem_info.base_address + svc_mem_info.size;
if (svc_mem_info.state != Kernel::Svc::MemoryState::Code ||
svc_mem_info.permission != Kernel::Svc::MemoryPermission::Read) {
return cur_addr - 1;
}
// Expect: rw- CodeData (.data)
R_ASSERT(page_table.QueryInfo(std::addressof(mem_info), std::addressof(page_info), cur_addr));
svc_mem_info = mem_info.GetSvcMemoryInfo();
cur_addr = svc_mem_info.base_address + svc_mem_info.size;
return cur_addr - 1;
}
static Loader::AppLoader::Modules FindModules(Core::System& system) {
Loader::AppLoader::Modules modules;
auto& page_table = system.ApplicationProcess()->GetPageTable();
auto& memory = system.ApplicationMemory();
VAddr cur_addr = 0;
// Look for executable sections in Code or AliasCode regions.
while (true) {
Kernel::KMemoryInfo mem_info{};
Kernel::Svc::PageInfo page_info{};
R_ASSERT(
page_table.QueryInfo(std::addressof(mem_info), std::addressof(page_info), cur_addr));
auto svc_mem_info = mem_info.GetSvcMemoryInfo();
if (svc_mem_info.permission == Kernel::Svc::MemoryPermission::ReadExecute &&
(svc_mem_info.state == Kernel::Svc::MemoryState::Code ||
svc_mem_info.state == Kernel::Svc::MemoryState::AliasCode)) {
// Try to read the module name from its path.
constexpr s32 PathLengthMax = 0x200;
struct {
u32 zero;
s32 path_length;
std::array<char, PathLengthMax> path;
} module_path;
if (memory.ReadBlock(svc_mem_info.base_address + svc_mem_info.size, &module_path,
sizeof(module_path))) {
if (module_path.zero == 0 && module_path.path_length > 0) {
// Truncate module name.
module_path.path[PathLengthMax - 1] = '\0';
// Ignore leading directories.
char* path_pointer = module_path.path.data();
for (s32 i = 0; i < std::min(PathLengthMax, module_path.path_length) &&
module_path.path[i] != '\0';
i++) {
if (module_path.path[i] == '/' || module_path.path[i] == '\\') {
path_pointer = module_path.path.data() + i + 1;
}
}
// Insert output.
modules.emplace(svc_mem_info.base_address, path_pointer);
}
}
}
// Check if we're done.
const uintptr_t next_address = svc_mem_info.base_address + svc_mem_info.size;
if (next_address <= cur_addr) {
break;
}
cur_addr = next_address;
}
return modules;
}
static VAddr FindMainModuleEntrypoint(Core::System& system) {
Loader::AppLoader::Modules modules;
system.GetAppLoader().ReadNSOModules(modules);
// Do we have a module named main?
const auto main = std::find_if(modules.begin(), modules.end(),
[](const auto& key) { return key.second == "main"; });
if (main != modules.end()) {
return main->first;
}
// Do we have any loaded executable sections?
modules = FindModules(system);
if (!modules.empty()) {
return modules.begin()->first;
}
// As a last resort, use the start of the code region.
return GetInteger(system.ApplicationProcess()->GetPageTable().GetCodeRegionStart());
}
void GDBStub::HandleQuery(std::string_view command) {
if (command.starts_with("TStatus")) {
// no tracepoint support
@ -573,21 +687,10 @@ void GDBStub::HandleQuery(std::string_view command) {
const auto target_xml{arch->GetTargetXML()};
SendReply(PaginateBuffer(target_xml, command.substr(30)));
} else if (command.starts_with("Offsets")) {
Loader::AppLoader::Modules modules;
system.GetAppLoader().ReadNSOModules(modules);
const auto main = std::find_if(modules.begin(), modules.end(),
[](const auto& key) { return key.second == "main"; });
if (main != modules.end()) {
SendReply(fmt::format("TextSeg={:x}", main->first));
} else {
SendReply(fmt::format(
"TextSeg={:x}",
GetInteger(system.ApplicationProcess()->GetPageTable().GetCodeRegionStart())));
}
const auto main_offset = FindMainModuleEntrypoint(system);
SendReply(fmt::format("TextSeg={:x}", main_offset));
} else if (command.starts_with("Xfer:libraries:read::")) {
Loader::AppLoader::Modules modules;
system.GetAppLoader().ReadNSOModules(modules);
auto modules = FindModules(system);
std::string buffer;
buffer += R"(<?xml version="1.0"?>)";
@ -727,37 +830,6 @@ static constexpr const char* GetMemoryPermissionString(const Kernel::Svc::Memory
}
}
static VAddr GetModuleEnd(Kernel::KProcessPageTable& page_table, VAddr base) {
Kernel::KMemoryInfo mem_info;
Kernel::Svc::MemoryInfo svc_mem_info;
Kernel::Svc::PageInfo page_info;
VAddr cur_addr{base};
// Expect: r-x Code (.text)
R_ASSERT(page_table.QueryInfo(std::addressof(mem_info), std::addressof(page_info), cur_addr));
svc_mem_info = mem_info.GetSvcMemoryInfo();
cur_addr = svc_mem_info.base_address + svc_mem_info.size;
if (svc_mem_info.state != Kernel::Svc::MemoryState::Code ||
svc_mem_info.permission != Kernel::Svc::MemoryPermission::ReadExecute) {
return cur_addr - 1;
}
// Expect: r-- Code (.rodata)
R_ASSERT(page_table.QueryInfo(std::addressof(mem_info), std::addressof(page_info), cur_addr));
svc_mem_info = mem_info.GetSvcMemoryInfo();
cur_addr = svc_mem_info.base_address + svc_mem_info.size;
if (svc_mem_info.state != Kernel::Svc::MemoryState::Code ||
svc_mem_info.permission != Kernel::Svc::MemoryPermission::Read) {
return cur_addr - 1;
}
// Expect: rw- CodeData (.data)
R_ASSERT(page_table.QueryInfo(std::addressof(mem_info), std::addressof(page_info), cur_addr));
svc_mem_info = mem_info.GetSvcMemoryInfo();
cur_addr = svc_mem_info.base_address + svc_mem_info.size;
return cur_addr - 1;
}
void GDBStub::HandleRcmd(const std::vector<u8>& command) {
std::string_view command_str{reinterpret_cast<const char*>(&command[0]), command.size()};
std::string reply;
@ -784,8 +856,7 @@ void GDBStub::HandleRcmd(const std::vector<u8>& command) {
reply = "Fastmem is not enabled.\n";
}
} else if (command_str == "get info") {
Loader::AppLoader::Modules modules;
system.GetAppLoader().ReadNSOModules(modules);
auto modules = FindModules(system);
reply = fmt::format("Process: {:#x} ({})\n"
"Program Id: {:#018x}\n",