/* * Copyright (C) 2017 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include <stdint.h> #include <functional> #include <unwindstack/Elf.h> #include <unwindstack/MachineMips.h> #include <unwindstack/MapInfo.h> #include <unwindstack/Memory.h> #include <unwindstack/RegsMips.h> #include <unwindstack/UcontextMips.h> #include <unwindstack/UserMips.h> namespace unwindstack { RegsMips::RegsMips() : RegsImpl<uint32_t>(MIPS_REG_LAST, Location(LOCATION_REGISTER, MIPS_REG_RA)) {} ArchEnum RegsMips::Arch() { return ARCH_MIPS; } uint64_t RegsMips::pc() { return regs_[MIPS_REG_PC]; } uint64_t RegsMips::sp() { return regs_[MIPS_REG_SP]; } void RegsMips::set_pc(uint64_t pc) { regs_[MIPS_REG_PC] = static_cast<uint32_t>(pc); } void RegsMips::set_sp(uint64_t sp) { regs_[MIPS_REG_SP] = static_cast<uint32_t>(sp); } uint64_t RegsMips::GetPcAdjustment(uint64_t rel_pc, Elf*) { if (rel_pc < 8) { return 0; } // For now, just assume no compact branches return 8; } bool RegsMips::SetPcFromReturnAddress(Memory*) { uint32_t ra = regs_[MIPS_REG_RA]; if (regs_[MIPS_REG_PC] == ra) { return false; } regs_[MIPS_REG_PC] = ra; return true; } void RegsMips::IterateRegisters(std::function<void(const char*, uint64_t)> fn) { fn("r0", regs_[MIPS_REG_R0]); fn("r1", regs_[MIPS_REG_R1]); fn("r2", regs_[MIPS_REG_R2]); fn("r3", regs_[MIPS_REG_R3]); fn("r4", regs_[MIPS_REG_R4]); fn("r5", regs_[MIPS_REG_R5]); fn("r6", regs_[MIPS_REG_R6]); fn("r7", regs_[MIPS_REG_R7]); fn("r8", regs_[MIPS_REG_R8]); fn("r9", regs_[MIPS_REG_R9]); fn("r10", regs_[MIPS_REG_R10]); fn("r11", regs_[MIPS_REG_R11]); fn("r12", regs_[MIPS_REG_R12]); fn("r13", regs_[MIPS_REG_R13]); fn("r14", regs_[MIPS_REG_R14]); fn("r15", regs_[MIPS_REG_R15]); fn("r16", regs_[MIPS_REG_R16]); fn("r17", regs_[MIPS_REG_R17]); fn("r18", regs_[MIPS_REG_R18]); fn("r19", regs_[MIPS_REG_R19]); fn("r20", regs_[MIPS_REG_R20]); fn("r21", regs_[MIPS_REG_R21]); fn("r22", regs_[MIPS_REG_R22]); fn("r23", regs_[MIPS_REG_R23]); fn("r24", regs_[MIPS_REG_R24]); fn("r25", regs_[MIPS_REG_R25]); fn("r26", regs_[MIPS_REG_R26]); fn("r27", regs_[MIPS_REG_R27]); fn("r28", regs_[MIPS_REG_R28]); fn("sp", regs_[MIPS_REG_SP]); fn("r30", regs_[MIPS_REG_R30]); fn("ra", regs_[MIPS_REG_RA]); fn("pc", regs_[MIPS_REG_PC]); } Regs* RegsMips::Read(void* remote_data) { mips_user_regs* user = reinterpret_cast<mips_user_regs*>(remote_data); RegsMips* regs = new RegsMips(); uint32_t* reg_data = reinterpret_cast<uint32_t*>(regs->RawData()); memcpy(regs->RawData(), &user->regs[MIPS32_EF_R0], (MIPS_REG_R31 + 1) * sizeof(uint32_t)); reg_data[MIPS_REG_PC] = user->regs[MIPS32_EF_CP0_EPC]; return regs; } Regs* RegsMips::CreateFromUcontext(void* ucontext) { mips_ucontext_t* mips_ucontext = reinterpret_cast<mips_ucontext_t*>(ucontext); RegsMips* regs = new RegsMips(); // Copy 64 bit sc_regs over to 32 bit regs for (int i = 0; i < 32; i++) { (*regs)[MIPS_REG_R0 + i] = mips_ucontext->uc_mcontext.sc_regs[i]; } (*regs)[MIPS_REG_PC] = mips_ucontext->uc_mcontext.sc_pc; return regs; } bool RegsMips::StepIfSignalHandler(uint64_t rel_pc, Elf* elf, Memory* process_memory) { uint64_t data; uint64_t offset = 0; Memory* elf_memory = elf->memory(); // Read from elf memory since it is usually more expensive to read from // process memory. if (!elf_memory->Read(rel_pc, &data, sizeof(data))) { return false; } // Look for the kernel sigreturn functions. // __vdso_rt_sigreturn: // 0x24021061 li v0, 0x1061 // 0x0000000c syscall // __vdso_sigreturn: // 0x24021017 li v0, 0x1017 // 0x0000000c syscall if (data == 0x0000000c24021061ULL) { // vdso_rt_sigreturn => read rt_sigframe // offset = siginfo offset + sizeof(siginfo) + uc_mcontext offset + sc_pc offset offset = 24 + 128 + 24 + 8; } else if (data == 0x0000000c24021017LL) { // vdso_sigreturn => read sigframe // offset = sigcontext offset + sc_pc offset offset = 24 + 8; } else { return false; } // read sc_pc and sc_regs[32] from stack uint64_t values[MIPS_REG_LAST]; if (!process_memory->Read(regs_[MIPS_REG_SP] + offset, values, sizeof(values))) { return false; } // Copy 64 bit sc_pc over to 32 bit regs_[MIPS_REG_PC] regs_[MIPS_REG_PC] = values[0]; // Copy 64 bit sc_regs over to 32 bit regs for (int i = 0; i < 32; i++) { regs_[MIPS_REG_R0 + i] = values[1 + i]; } return true; } Regs* RegsMips::Clone() { return new RegsMips(*this); } } // namespace unwindstack