From 039983b915a130df66e3d4bd1f0705519386f09c Mon Sep 17 00:00:00 2001 From: Dimitar Vlahovski Date: Thu, 20 Oct 2016 16:01:36 +0000 Subject: [PATCH] Minidump plugin: redesign the x86_64 register context Summary: I misunderstood the format of the register context layout. I thought it was a dynamically changing structure, and that it's size depended on context_flags. It turned out that it always has the same fixed layout and size, and the context_flags says which fields of the struct have valid values. This required a minor redesign of the register context class. The layout inconsistency, however, was not a "problem" before (e.g. the plugin was working) because there also was a bug with checking context_flags - the code was parsing the entire struct regardless of context_flags. This bug is also fixed in this commit. Reviewers: labath, zturner Subscribers: lldb-commits, amccarth Differential Revision: https://reviews.llvm.org/D25677 llvm-svn: 284741 --- .../minidump/RegisterContextMinidump_x86_64.cpp | 147 ++++++----------- .../minidump/RegisterContextMinidump_x86_64.h | 180 ++++++++++++++------- 2 files changed, 173 insertions(+), 154 deletions(-) diff --git a/lldb/source/Plugins/Process/minidump/RegisterContextMinidump_x86_64.cpp b/lldb/source/Plugins/Process/minidump/RegisterContextMinidump_x86_64.cpp index 481779d..a3812cb 100644 --- a/lldb/source/Plugins/Process/minidump/RegisterContextMinidump_x86_64.cpp +++ b/lldb/source/Plugins/Process/minidump/RegisterContextMinidump_x86_64.cpp @@ -19,18 +19,11 @@ using namespace lldb_private; using namespace minidump; -void writeRegister(llvm::ArrayRef ®_src, - llvm::MutableArrayRef reg_dest) { - memcpy(reg_dest.data(), reg_src.data(), reg_dest.size()); - reg_src = reg_src.drop_front(reg_dest.size()); -} - llvm::MutableArrayRef getDestRegister(uint8_t *context, - uint32_t lldb_reg_num, const RegisterInfo ®) { auto bytes = reg.mutable_data(context); - switch (lldb_reg_num) { + switch (reg.kinds[lldb::eRegisterKindLLDB]) { case lldb_cs_x86_64: case lldb_ds_x86_64: case lldb_es_x86_64: @@ -48,6 +41,12 @@ llvm::MutableArrayRef getDestRegister(uint8_t *context, } } +void writeRegister(const void *reg_src, uint8_t *context, + const RegisterInfo ®) { + llvm::MutableArrayRef reg_dest = getDestRegister(context, reg); + memcpy(reg_dest.data(), reg_src, reg_dest.size()); +} + lldb::DataBufferSP lldb_private::minidump::ConvertMinidumpContextToRegIface( llvm::ArrayRef source_data, RegisterInfoInterface *target_reg_interface) { @@ -58,98 +57,54 @@ lldb::DataBufferSP lldb_private::minidump::ConvertMinidumpContextToRegIface( new DataBufferHeap(target_reg_interface->GetGPRSize(), 0)); uint8_t *result_base = result_context_buf->GetBytes(); - source_data = source_data.drop_front(6 * 8); // p[1-6] home registers - const uint32_t *context_flags; - consumeObject(source_data, context_flags); - const uint32_t x86_64_Flag = - static_cast(MinidumpContext_x86_64_Flags::x86_64_Flag); - const uint32_t ControlFlag = - static_cast(MinidumpContext_x86_64_Flags::Control); - const uint32_t IntegerFlag = - static_cast(MinidumpContext_x86_64_Flags::Integer); - const uint32_t SegmentsFlag = - static_cast(MinidumpContext_x86_64_Flags::Segments); - const uint32_t DebugRegistersFlag = - static_cast(MinidumpContext_x86_64_Flags::DebugRegisters); - - if (!(*context_flags & x86_64_Flag)) { - return result_context_buf; // error - } - - source_data = source_data.drop_front(4); // mx_csr - - if (*context_flags & ControlFlag) { - writeRegister(source_data, getDestRegister(result_base, lldb_cs_x86_64, - reg_info[lldb_cs_x86_64])); - } - - if (*context_flags & SegmentsFlag) { - writeRegister(source_data, getDestRegister(result_base, lldb_ds_x86_64, - reg_info[lldb_ds_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_es_x86_64, - reg_info[lldb_es_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_fs_x86_64, - reg_info[lldb_fs_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_gs_x86_64, - reg_info[lldb_gs_x86_64])); - } - - if (*context_flags & ControlFlag) { - writeRegister(source_data, getDestRegister(result_base, lldb_ss_x86_64, - reg_info[lldb_ss_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_rflags_x86_64, - reg_info[lldb_rflags_x86_64])); - } - - if (*context_flags & DebugRegistersFlag) { - source_data = - source_data.drop_front(6 * 8); // 6 debug registers 64 bit each - } - - if (*context_flags & IntegerFlag) { - writeRegister(source_data, getDestRegister(result_base, lldb_rax_x86_64, - reg_info[lldb_rax_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_rcx_x86_64, - reg_info[lldb_rcx_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_rdx_x86_64, - reg_info[lldb_rdx_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_rbx_x86_64, - reg_info[lldb_rbx_x86_64])); - } - - if (*context_flags & ControlFlag) { - writeRegister(source_data, getDestRegister(result_base, lldb_rsp_x86_64, - reg_info[lldb_rsp_x86_64])); + if (source_data.size() < sizeof(MinidumpContext_x86_64)) + return nullptr; + + const MinidumpContext_x86_64 *context; + consumeObject(source_data, context); + + const MinidumpContext_x86_64_Flags context_flags = + static_cast( + static_cast(context->context_flags)); + auto x86_64_Flag = MinidumpContext_x86_64_Flags::x86_64_Flag; + auto ControlFlag = MinidumpContext_x86_64_Flags::Control; + auto IntegerFlag = MinidumpContext_x86_64_Flags::Integer; + auto SegmentsFlag = MinidumpContext_x86_64_Flags::Segments; + + if ((context_flags & x86_64_Flag) != x86_64_Flag) + return nullptr; + + if ((context_flags & ControlFlag) == ControlFlag) { + writeRegister(&context->cs, result_base, reg_info[lldb_cs_x86_64]); + writeRegister(&context->ss, result_base, reg_info[lldb_ss_x86_64]); + writeRegister(&context->eflags, result_base, reg_info[lldb_rflags_x86_64]); + writeRegister(&context->rsp, result_base, reg_info[lldb_rsp_x86_64]); + writeRegister(&context->rip, result_base, reg_info[lldb_rip_x86_64]); } - if (*context_flags & IntegerFlag) { - writeRegister(source_data, getDestRegister(result_base, lldb_rbp_x86_64, - reg_info[lldb_rbp_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_rsi_x86_64, - reg_info[lldb_rsi_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_rdi_x86_64, - reg_info[lldb_rdi_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_r8_x86_64, - reg_info[lldb_r8_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_r9_x86_64, - reg_info[lldb_r9_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_r10_x86_64, - reg_info[lldb_r10_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_r11_x86_64, - reg_info[lldb_r11_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_r12_x86_64, - reg_info[lldb_r12_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_r13_x86_64, - reg_info[lldb_r13_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_r14_x86_64, - reg_info[lldb_r14_x86_64])); - writeRegister(source_data, getDestRegister(result_base, lldb_r15_x86_64, - reg_info[lldb_r15_x86_64])); + if ((context_flags & SegmentsFlag) == SegmentsFlag) { + writeRegister(&context->ds, result_base, reg_info[lldb_ds_x86_64]); + writeRegister(&context->es, result_base, reg_info[lldb_es_x86_64]); + writeRegister(&context->fs, result_base, reg_info[lldb_fs_x86_64]); + writeRegister(&context->gs, result_base, reg_info[lldb_gs_x86_64]); } - if (*context_flags & ControlFlag) { - writeRegister(source_data, getDestRegister(result_base, lldb_rip_x86_64, - reg_info[lldb_rip_x86_64])); + if ((context_flags & IntegerFlag) == IntegerFlag) { + writeRegister(&context->rax, result_base, reg_info[lldb_rax_x86_64]); + writeRegister(&context->rcx, result_base, reg_info[lldb_rcx_x86_64]); + writeRegister(&context->rdx, result_base, reg_info[lldb_rdx_x86_64]); + writeRegister(&context->rbx, result_base, reg_info[lldb_rbx_x86_64]); + writeRegister(&context->rbp, result_base, reg_info[lldb_rbp_x86_64]); + writeRegister(&context->rsi, result_base, reg_info[lldb_rsi_x86_64]); + writeRegister(&context->rdi, result_base, reg_info[lldb_rdi_x86_64]); + writeRegister(&context->r8, result_base, reg_info[lldb_r8_x86_64]); + writeRegister(&context->r9, result_base, reg_info[lldb_r9_x86_64]); + writeRegister(&context->r10, result_base, reg_info[lldb_r10_x86_64]); + writeRegister(&context->r11, result_base, reg_info[lldb_r11_x86_64]); + writeRegister(&context->r12, result_base, reg_info[lldb_r12_x86_64]); + writeRegister(&context->r13, result_base, reg_info[lldb_r13_x86_64]); + writeRegister(&context->r14, result_base, reg_info[lldb_r14_x86_64]); + writeRegister(&context->r15, result_base, reg_info[lldb_r15_x86_64]); } // TODO parse the floating point registers diff --git a/lldb/source/Plugins/Process/minidump/RegisterContextMinidump_x86_64.h b/lldb/source/Plugins/Process/minidump/RegisterContextMinidump_x86_64.h index a25a814..2524089 100644 --- a/lldb/source/Plugins/Process/minidump/RegisterContextMinidump_x86_64.h +++ b/lldb/source/Plugins/Process/minidump/RegisterContextMinidump_x86_64.h @@ -21,6 +21,7 @@ #include "llvm/ADT/ArrayRef.h" #include "llvm/ADT/BitmaskEnum.h" +#include "llvm/Support/Endian.h" // C includes // C++ includes @@ -29,63 +30,6 @@ namespace lldb_private { namespace minidump { -// The content of the Minidump register context is as follows: -// (for reference see breakpad's source or WinNT.h) -// Register parameter home addresses: (p1_home .. p6_home) -// - uint64_t p1_home -// - uint64_t p2_home -// - uint64_t p3_home -// - uint64_t p4_home -// - uint64_t p5_home -// - uint64_t p6_home -// -// - uint32_t context_flags - field that determines the layout of the structure -// and which parts of it are populated -// - uint32_t mx_csr -// -// - uint16_t cs - included if MinidumpContext_x86_64_Flags::Control -// -// - uint16_t ds - included if MinidumpContext_x86_64_Flags::Segments -// - uint16_t es - included if MinidumpContext_x86_64_Flags::Segments -// - uint16_t fs - included if MinidumpContext_x86_64_Flags::Segments -// - uint16_t gs - included if MinidumpContext_x86_64_Flags::Segments -// -// - uint16_t ss - included if MinidumpContext_x86_64_Flags::Control -// - uint32_t rflags - included if MinidumpContext_x86_64_Flags::Control -// -// Debug registers: (included if MinidumpContext_x86_64_Flags::DebugRegisters) -// - uint64_t dr0 -// - uint64_t dr1 -// - uint64_t dr2 -// - uint64_t dr3 -// - uint64_t dr6 -// - uint64_t dr7 -// -// The next 4 registers are included if MinidumpContext_x86_64_Flags::Integer -// - uint64_t rax -// - uint64_t rcx -// - uint64_t rdx -// - uint64_t rbx -// -// - uint64_t rsp - included if MinidumpContext_x86_64_Flags::Control -// -// The next 11 registers are included if MinidumpContext_x86_64_Flags::Integer -// - uint64_t rbp -// - uint64_t rsi -// - uint64_t rdi -// - uint64_t r8 -// - uint64_t r9 -// - uint64_t r10 -// - uint64_t r11 -// - uint64_t r12 -// - uint64_t r13 -// - uint64_t r14 -// - uint64_t r15 -// -// - uint64_t rip - included if MinidumpContext_x86_64_Flags::Control -// -// TODO: add floating point registers here - // This function receives an ArrayRef pointing to the bytes of the Minidump // register context and returns a DataBuffer that's ordered by the offsets // specified in the RegisterInfoInterface argument @@ -94,8 +38,128 @@ lldb::DataBufferSP ConvertMinidumpContextToRegIface(llvm::ArrayRef source_data, RegisterInfoInterface *target_reg_interface); +struct Uint128 { + llvm::support::ulittle64_t high; + llvm::support::ulittle64_t low; +}; + +// Reference: see breakpad/crashpad source or WinNT.h +struct MinidumpXMMSaveArea32AMD64 { + llvm::support::ulittle16_t control_word; + llvm::support::ulittle16_t status_word; + uint8_t tag_word; + uint8_t reserved1; + llvm::support::ulittle16_t error_opcode; + llvm::support::ulittle32_t error_offset; + llvm::support::ulittle16_t error_selector; + llvm::support::ulittle16_t reserved2; + llvm::support::ulittle32_t data_offset; + llvm::support::ulittle16_t data_selector; + llvm::support::ulittle16_t reserved3; + llvm::support::ulittle32_t mx_csr; + llvm::support::ulittle32_t mx_csr_mask; + Uint128 float_registers[8]; + Uint128 xmm_registers[16]; + uint8_t reserved4[96]; +}; + +struct MinidumpContext_x86_64 { + // Register parameter home addresses. + llvm::support::ulittle64_t p1_home; + llvm::support::ulittle64_t p2_home; + llvm::support::ulittle64_t p3_home; + llvm::support::ulittle64_t p4_home; + llvm::support::ulittle64_t p5_home; + llvm::support::ulittle64_t p6_home; + + // The context_flags field determines and which parts + // of the structure are populated (have valid values) + llvm::support::ulittle32_t context_flags; + llvm::support::ulittle32_t mx_csr; + + // The next register is included with + // MinidumpContext_x86_64_Flags::Control + llvm::support::ulittle16_t cs; + + // The next 4 registers are included with + // MinidumpContext_x86_64_Flags::Segments + llvm::support::ulittle16_t ds; + llvm::support::ulittle16_t es; + llvm::support::ulittle16_t fs; + llvm::support::ulittle16_t gs; + + // The next 2 registers are included with + // MinidumpContext_x86_64_Flags::Control + llvm::support::ulittle16_t ss; + llvm::support::ulittle32_t eflags; + + // The next 6 registers are included with + // MinidumpContext_x86_64_Flags::DebugRegisters + llvm::support::ulittle64_t dr0; + llvm::support::ulittle64_t dr1; + llvm::support::ulittle64_t dr2; + llvm::support::ulittle64_t dr3; + llvm::support::ulittle64_t dr6; + llvm::support::ulittle64_t dr7; + + // The next 4 registers are included with + // MinidumpContext_x86_64_Flags::Integer + llvm::support::ulittle64_t rax; + llvm::support::ulittle64_t rcx; + llvm::support::ulittle64_t rdx; + llvm::support::ulittle64_t rbx; + + // The next register is included with + // MinidumpContext_x86_64_Flags::Control + llvm::support::ulittle64_t rsp; + + // The next 11 registers are included with + // MinidumpContext_x86_64_Flags::Integer + llvm::support::ulittle64_t rbp; + llvm::support::ulittle64_t rsi; + llvm::support::ulittle64_t rdi; + llvm::support::ulittle64_t r8; + llvm::support::ulittle64_t r9; + llvm::support::ulittle64_t r10; + llvm::support::ulittle64_t r11; + llvm::support::ulittle64_t r12; + llvm::support::ulittle64_t r13; + llvm::support::ulittle64_t r14; + llvm::support::ulittle64_t r15; + + // The next register is included with + // MinidumpContext_x86_64_Flags::Control + llvm::support::ulittle64_t rip; + + // The next set of registers are included with + // MinidumpContext_x86_64_Flags:FloatingPoint + union FPR { + MinidumpXMMSaveArea32AMD64 flt_save; + struct { + Uint128 header[2]; + Uint128 legacy[8]; + Uint128 xmm[16]; + } sse_registers; + }; + + enum { + VRCount = 26, + }; + + Uint128 vector_register[VRCount]; + llvm::support::ulittle64_t vector_control; + + // The next 5 registers are included with + // MinidumpContext_x86_64_Flags::DebugRegisters + llvm::support::ulittle64_t debug_control; + llvm::support::ulittle64_t last_branch_to_rip; + llvm::support::ulittle64_t last_branch_from_rip; + llvm::support::ulittle64_t last_exception_to_rip; + llvm::support::ulittle64_t last_exception_from_rip; +}; + // For context_flags. These values indicate the type of -// context stored in the structure. The high 24 bits identify the CPU, the +// context stored in the structure. The high 24 bits identify the CPU, the // low 8 bits identify the type of context saved. LLVM_ENABLE_BITMASK_ENUMS_IN_NAMESPACE(); -- 2.7.4