From fbda084acb85cbd9f0a42bd17e89fd89cc460f31 Mon Sep 17 00:00:00 2001 From: Liam Date: Mon, 14 Aug 2023 16:33:27 -0400 Subject: [PATCH] gdbstub: fixup replaced instruction bytes in memory reads --- src/core/debugger/gdbstub.cpp | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/src/core/debugger/gdbstub.cpp b/src/core/debugger/gdbstub.cpp index 0f839d5b4..e55831f27 100644 --- a/src/core/debugger/gdbstub.cpp +++ b/src/core/debugger/gdbstub.cpp @@ -263,6 +263,23 @@ void GDBStub::ExecuteCommand(std::string_view packet, std::vector mem(size); if (system.ApplicationMemory().ReadBlock(addr, mem.data(), size)) { + // Restore any bytes belonging to replaced instructions. + auto it = replaced_instructions.lower_bound(addr); + for (; it != replaced_instructions.end() && it->first < addr + size; it++) { + // Get the bytes of the instruction we previously replaced. + const u32 original_bytes = it->second; + + // Calculate where to start writing to the output buffer. + const size_t output_offset = it->first - addr; + + // Calculate how many bytes to write. + // The loop condition ensures output_offset < size. + const size_t n = std::min(size - output_offset, sizeof(u32)); + + // Write the bytes to the output buffer. + std::memcpy(mem.data() + output_offset, &original_bytes, n); + } + SendReply(Common::HexToString(mem)); } else { SendReply(GDB_STUB_REPLY_ERR);