HackStudio: Correctly handle invalid addresses during backtrace creation

This fixes a bug where we previously would hang if we couldn't find a
library containing the current program counter.
This commit is contained in:
Sönke Holz 2024-01-04 02:03:08 +01:00 committed by Andrew Kaster
parent 256f0c9064
commit 6f6a2dc319

View file

@ -39,22 +39,26 @@ Vector<BacktraceModel::FrameInfo> BacktraceModel::create_backtrace(Debug::Proces
size_t frame_index = 0;
do {
auto lib = inspector.library_at(current_program_counter);
if (!lib)
continue;
// After the first frame, current_instruction holds the return address from the function call.
// We need to go back to the 'call' instruction to get accurate source position information.
if (frame_index > 0)
--current_program_counter;
ByteString name = lib->debug_info->elf().symbolicate(current_program_counter - lib->base_address);
if (name.is_empty()) {
dbgln("BacktraceModel: couldn't find containing function for address: {:p} (library={})", current_program_counter, lib->name);
name = "<missing>";
if (lib) {
// After the first frame, current_instruction holds the return address from the function call.
// We need to go back to the 'call' instruction to get accurate source position information.
if (frame_index > 0)
--current_program_counter;
ByteString name = lib->debug_info->elf().symbolicate(current_program_counter - lib->base_address);
if (name.is_empty()) {
dbgln("BacktraceModel: couldn't find containing function for address: {:p} (library={})", current_program_counter, lib->name);
name = "<missing>";
}
auto source_position = lib->debug_info->get_source_position(current_program_counter - lib->base_address);
frames.append({ name, current_program_counter, current_frame_pointer, source_position });
} else {
dbgln("BacktraceModel: couldn't find containing library for address: {:p}", current_program_counter);
frames.append({ "<missing>", current_program_counter, current_frame_pointer, {} });
}
auto source_position = lib->debug_info->get_source_position(current_program_counter - lib->base_address);
frames.append({ name, current_program_counter, current_frame_pointer, source_position });
auto frame_info = Debug::StackFrameUtils::get_info(inspector, current_frame_pointer);
VERIFY(frame_info.has_value());
current_program_counter = frame_info.value().return_address;