backtrace-x86.c revision 6b3bab39d128947bf51deefe6a28c247cafd7bae
110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown/* 210484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * Copyright (C) 2011 The Android Open Source Project 310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * 410484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * Licensed under the Apache License, Version 2.0 (the "License"); 510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * you may not use this file except in compliance with the License. 610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * You may obtain a copy of the License at 710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * 810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * http://www.apache.org/licenses/LICENSE-2.0 910484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * 1010484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * Unless required by applicable law or agreed to in writing, software 1110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * distributed under the License is distributed on an "AS IS" BASIS, 1210484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 1310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * See the License for the specific language governing permissions and 1410484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * limitations under the License. 1510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown */ 1610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 1710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown/* 1810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown * Backtracing functions for x86. 1910484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown */ 2010484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 2110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#define LOG_TAG "Corkscrew" 2210484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown//#define LOG_NDEBUG 0 2310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 2410484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include "../backtrace-arch.h" 2510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include "../backtrace-helper.h" 2610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include <corkscrew/ptrace.h> 2710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 2810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include <stdlib.h> 2910484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include <signal.h> 3010484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include <stdbool.h> 3110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include <limits.h> 3210484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include <errno.h> 3310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include <sys/ptrace.h> 3410484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown#include <cutils/log.h> 3510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 366b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes#if defined(__BIONIC__) 376b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes 386b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes// Bionic offers the Linux kernel headers. 396b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes#include <asm/sigcontext.h> 406b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes#include <asm/ucontext.h> 416b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughestypedef struct ucontext ucontext_t; 426b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes 436b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes#else 446b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes 456b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes// glibc has its own renaming of the Linux kernel's structures. 4671363a8075e7916c2166cbdd8a0bf5a180ed4d54Elliott Hughes#define __USE_GNU // For REG_EBP, REG_ESP, and REG_EIP. 4771363a8075e7916c2166cbdd8a0bf5a180ed4d54Elliott Hughes#include <ucontext.h> 4810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 496b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes#endif 506b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes 5110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown/* Unwind state. */ 5210484a068412613aaf3924f63a0b2f61400c7d1eJeff Browntypedef struct { 5310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown uint32_t ebp; 5410484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown uint32_t eip; 5510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown uint32_t esp; 5610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown} unwind_state_t; 5710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 58f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brownuintptr_t rewind_pc_arch(const memory_t* memory, uintptr_t pc) { 59f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown // TODO: Implement for x86. 60f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown return pc; 61f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown} 62f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown 63f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brownstatic ssize_t unwind_backtrace_common(const memory_t* memory, 64f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown const map_info_t* map_info_list, 6510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown unwind_state_t* state, backtrace_frame_t* backtrace, 6610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown size_t ignore_depth, size_t max_depth) { 6710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown size_t ignored_frames = 0; 6810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown size_t returned_frames = 0; 6910484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 70f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown for (size_t index = 0; state->ebp && returned_frames < max_depth; index++) { 71f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown backtrace_frame_t* frame = add_backtrace_entry( 72f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown index ? rewind_pc_arch(memory, state->eip) : state->eip, 7310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown backtrace, ignore_depth, max_depth, 7410484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown &ignored_frames, &returned_frames); 7510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown uint32_t next_esp = state->ebp + 8; 7610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown if (frame) { 7710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown frame->stack_top = state->esp; 7810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown if (state->esp < next_esp) { 7910484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown frame->stack_size = next_esp - state->esp; 8010484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown } 8110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown } 8210484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown state->esp = next_esp; 83f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown if (!try_get_word(memory, state->ebp + 4, &state->eip) 84f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown || !try_get_word(memory, state->ebp, &state->ebp) 8510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown || !state->eip) { 8610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown break; 8710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown } 8810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown } 8910484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 9010484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown return returned_frames; 9110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown} 9210484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 9310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brownssize_t unwind_backtrace_signal_arch(siginfo_t* siginfo, void* sigcontext, 94f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown const map_info_t* map_info_list, 9510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown backtrace_frame_t* backtrace, size_t ignore_depth, size_t max_depth) { 9610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown const ucontext_t* uc = (const ucontext_t*)sigcontext; 9710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 9810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown unwind_state_t state; 996b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes#if defined(__BIONIC__) 1006b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes state.ebp = uc->uc_mcontext.ebp; 1016b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes state.esp = uc->uc_mcontext.esp; 1026b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes state.eip = uc->uc_mcontext.eip; 1036b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes#else 10471363a8075e7916c2166cbdd8a0bf5a180ed4d54Elliott Hughes state.ebp = uc->uc_mcontext.gregs[REG_EBP]; 10571363a8075e7916c2166cbdd8a0bf5a180ed4d54Elliott Hughes state.esp = uc->uc_mcontext.gregs[REG_ESP]; 10671363a8075e7916c2166cbdd8a0bf5a180ed4d54Elliott Hughes state.eip = uc->uc_mcontext.gregs[REG_EIP]; 1076b3bab39d128947bf51deefe6a28c247cafd7baeElliott Hughes#endif 10810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 109f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown memory_t memory; 110f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown init_memory(&memory, map_info_list); 111f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown return unwind_backtrace_common(&memory, map_info_list, 112f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown &state, backtrace, ignore_depth, max_depth); 11310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown} 11410484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 11510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brownssize_t unwind_backtrace_ptrace_arch(pid_t tid, const ptrace_context_t* context, 11610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown backtrace_frame_t* backtrace, size_t ignore_depth, size_t max_depth) { 11710484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown pt_regs_x86_t regs; 11810484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown if (ptrace(PTRACE_GETREGS, tid, 0, ®s)) { 11910484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown return -1; 12010484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown } 12110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 12210484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown unwind_state_t state; 12310484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown state.ebp = regs.ebp; 12410484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown state.eip = regs.eip; 12510484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown state.esp = regs.esp; 12610484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown 127f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown memory_t memory; 128f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown init_memory_ptrace(&memory, tid); 129f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown return unwind_backtrace_common(&memory, context->map_info_list, 130f0c5872637a63e28e3cd314cfc915c07f76df9c6Jeff Brown &state, backtrace, ignore_depth, max_depth); 13110484a068412613aaf3924f63a0b2f61400c7d1eJeff Brown} 132