1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <stdint.h> 18 19 #include <functional> 20 21 #include <unwindstack/Elf.h> 22 #include <unwindstack/MachineX86_64.h> 23 #include <unwindstack/MapInfo.h> 24 #include <unwindstack/Memory.h> 25 #include <unwindstack/RegsX86_64.h> 26 #include <unwindstack/UcontextX86_64.h> 27 #include <unwindstack/UserX86_64.h> 28 29 namespace unwindstack { 30 31 RegsX86_64::RegsX86_64() : RegsImpl<uint64_t>(X86_64_REG_LAST, Location(LOCATION_SP_OFFSET, -8)) {} 32 33 ArchEnum RegsX86_64::Arch() { 34 return ARCH_X86_64; 35 } 36 37 uint64_t RegsX86_64::pc() { 38 return regs_[X86_64_REG_PC]; 39 } 40 41 uint64_t RegsX86_64::sp() { 42 return regs_[X86_64_REG_SP]; 43 } 44 45 void RegsX86_64::set_pc(uint64_t pc) { 46 regs_[X86_64_REG_PC] = pc; 47 } 48 49 void RegsX86_64::set_sp(uint64_t sp) { 50 regs_[X86_64_REG_SP] = sp; 51 } 52 53 uint64_t RegsX86_64::GetPcAdjustment(uint64_t rel_pc, Elf*) { 54 if (rel_pc == 0) { 55 return 0; 56 } 57 return 1; 58 } 59 60 bool RegsX86_64::SetPcFromReturnAddress(Memory* process_memory) { 61 // Attempt to get the return address from the top of the stack. 62 uint64_t new_pc; 63 if (!process_memory->ReadFully(regs_[X86_64_REG_SP], &new_pc, sizeof(new_pc)) || 64 new_pc == regs_[X86_64_REG_PC]) { 65 return false; 66 } 67 68 regs_[X86_64_REG_PC] = new_pc; 69 return true; 70 } 71 72 void RegsX86_64::IterateRegisters(std::function<void(const char*, uint64_t)> fn) { 73 fn("rax", regs_[X86_64_REG_RAX]); 74 fn("rbx", regs_[X86_64_REG_RBX]); 75 fn("rcx", regs_[X86_64_REG_RCX]); 76 fn("rdx", regs_[X86_64_REG_RDX]); 77 fn("r8", regs_[X86_64_REG_R8]); 78 fn("r9", regs_[X86_64_REG_R9]); 79 fn("r10", regs_[X86_64_REG_R10]); 80 fn("r11", regs_[X86_64_REG_R11]); 81 fn("r12", regs_[X86_64_REG_R12]); 82 fn("r13", regs_[X86_64_REG_R13]); 83 fn("r14", regs_[X86_64_REG_R14]); 84 fn("r15", regs_[X86_64_REG_R15]); 85 fn("rdi", regs_[X86_64_REG_RDI]); 86 fn("rsi", regs_[X86_64_REG_RSI]); 87 fn("rbp", regs_[X86_64_REG_RBP]); 88 fn("rsp", regs_[X86_64_REG_RSP]); 89 fn("rip", regs_[X86_64_REG_RIP]); 90 } 91 92 Regs* RegsX86_64::Read(void* remote_data) { 93 x86_64_user_regs* user = reinterpret_cast<x86_64_user_regs*>(remote_data); 94 95 RegsX86_64* regs = new RegsX86_64(); 96 (*regs)[X86_64_REG_RAX] = user->rax; 97 (*regs)[X86_64_REG_RBX] = user->rbx; 98 (*regs)[X86_64_REG_RCX] = user->rcx; 99 (*regs)[X86_64_REG_RDX] = user->rdx; 100 (*regs)[X86_64_REG_R8] = user->r8; 101 (*regs)[X86_64_REG_R9] = user->r9; 102 (*regs)[X86_64_REG_R10] = user->r10; 103 (*regs)[X86_64_REG_R11] = user->r11; 104 (*regs)[X86_64_REG_R12] = user->r12; 105 (*regs)[X86_64_REG_R13] = user->r13; 106 (*regs)[X86_64_REG_R14] = user->r14; 107 (*regs)[X86_64_REG_R15] = user->r15; 108 (*regs)[X86_64_REG_RDI] = user->rdi; 109 (*regs)[X86_64_REG_RSI] = user->rsi; 110 (*regs)[X86_64_REG_RBP] = user->rbp; 111 (*regs)[X86_64_REG_RSP] = user->rsp; 112 (*regs)[X86_64_REG_RIP] = user->rip; 113 114 return regs; 115 } 116 117 void RegsX86_64::SetFromUcontext(x86_64_ucontext_t* ucontext) { 118 // R8-R15 119 memcpy(®s_[X86_64_REG_R8], &ucontext->uc_mcontext.r8, 8 * sizeof(uint64_t)); 120 121 // Rest of the registers. 122 regs_[X86_64_REG_RDI] = ucontext->uc_mcontext.rdi; 123 regs_[X86_64_REG_RSI] = ucontext->uc_mcontext.rsi; 124 regs_[X86_64_REG_RBP] = ucontext->uc_mcontext.rbp; 125 regs_[X86_64_REG_RBX] = ucontext->uc_mcontext.rbx; 126 regs_[X86_64_REG_RDX] = ucontext->uc_mcontext.rdx; 127 regs_[X86_64_REG_RAX] = ucontext->uc_mcontext.rax; 128 regs_[X86_64_REG_RCX] = ucontext->uc_mcontext.rcx; 129 regs_[X86_64_REG_RSP] = ucontext->uc_mcontext.rsp; 130 regs_[X86_64_REG_RIP] = ucontext->uc_mcontext.rip; 131 } 132 133 Regs* RegsX86_64::CreateFromUcontext(void* ucontext) { 134 x86_64_ucontext_t* x86_64_ucontext = reinterpret_cast<x86_64_ucontext_t*>(ucontext); 135 136 RegsX86_64* regs = new RegsX86_64(); 137 regs->SetFromUcontext(x86_64_ucontext); 138 return regs; 139 } 140 141 bool RegsX86_64::StepIfSignalHandler(uint64_t rel_pc, Elf* elf, Memory* process_memory) { 142 uint64_t data; 143 Memory* elf_memory = elf->memory(); 144 // Read from elf memory since it is usually more expensive to read from 145 // process memory. 146 if (!elf_memory->ReadFully(rel_pc, &data, sizeof(data)) || data != 0x0f0000000fc0c748) { 147 return false; 148 } 149 150 uint16_t data2; 151 if (!elf_memory->ReadFully(rel_pc + 8, &data2, sizeof(data2)) || data2 != 0x0f05) { 152 return false; 153 } 154 155 // __restore_rt: 156 // 0x48 0xc7 0xc0 0x0f 0x00 0x00 0x00 mov $0xf,%rax 157 // 0x0f 0x05 syscall 158 // 0x0f nopl 0x0($rax) 159 160 // Read the mcontext data from the stack. 161 // sp points to the ucontext data structure, read only the mcontext part. 162 x86_64_ucontext_t x86_64_ucontext; 163 if (!process_memory->ReadFully(regs_[X86_64_REG_SP] + 0x28, &x86_64_ucontext.uc_mcontext, 164 sizeof(x86_64_mcontext_t))) { 165 return false; 166 } 167 SetFromUcontext(&x86_64_ucontext); 168 return true; 169 } 170 171 Regs* RegsX86_64::Clone() { 172 return new RegsX86_64(*this); 173 } 174 175 } // namespace unwindstack 176
