| /* system/debuggerd/debuggerd.c |
| ** |
| ** Copyright 2012, 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 <stddef.h> |
| #include <stdbool.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <stdio.h> |
| #include <errno.h> |
| #include <sys/types.h> |
| #include <sys/ptrace.h> |
| |
| #include <corkscrew/ptrace.h> |
| |
| #include <linux/user.h> |
| |
| #include "../utility.h" |
| #include "../machine.h" |
| |
| /* enable to dump memory pointed to by every register */ |
| #define DUMP_MEMORY_FOR_ALL_REGISTERS 1 |
| |
| #define R(x) ((unsigned int)(x)) |
| |
| static void dump_memory(log_t* log, pid_t tid, uintptr_t addr, bool at_fault) { |
| char code_buffer[64]; /* actual 8+1+((8+1)*4) + 1 == 45 */ |
| char ascii_buffer[32]; /* actual 16 + 1 == 17 */ |
| uintptr_t p, end; |
| |
| p = addr & ~3; |
| p -= 32; |
| if (p > addr) { |
| /* catch underflow */ |
| p = 0; |
| } |
| end = p + 80; |
| /* catch overflow; 'end - p' has to be multiples of 16 */ |
| while (end < p) |
| end -= 16; |
| |
| /* Dump the code around PC as: |
| * addr contents ascii |
| * 00008d34 ef000000 e8bd0090 e1b00000 512fff1e ............../Q |
| * 00008d44 ea00b1f9 e92d0090 e3a070fc ef000000 ......-..p...... |
| */ |
| while (p < end) { |
| char* asc_out = ascii_buffer; |
| |
| sprintf(code_buffer, "%08x ", p); |
| |
| int i; |
| for (i = 0; i < 4; i++) { |
| /* |
| * If we see (data == -1 && errno != 0), we know that the ptrace |
| * call failed, probably because we're dumping memory in an |
| * unmapped or inaccessible page. I don't know if there's |
| * value in making that explicit in the output -- it likely |
| * just complicates parsing and clarifies nothing for the |
| * enlightened reader. |
| */ |
| long data = ptrace(PTRACE_PEEKTEXT, tid, (void*)p, NULL); |
| sprintf(code_buffer + strlen(code_buffer), "%08lx ", data); |
| |
| int j; |
| for (j = 0; j < 4; j++) { |
| /* |
| * Our isprint() allows high-ASCII characters that display |
| * differently (often badly) in different viewers, so we |
| * just use a simpler test. |
| */ |
| char val = (data >> (j*8)) & 0xff; |
| if (val >= 0x20 && val < 0x7f) { |
| *asc_out++ = val; |
| } else { |
| *asc_out++ = '.'; |
| } |
| } |
| p += 4; |
| } |
| *asc_out = '\0'; |
| _LOG(log, !at_fault, " %s %s\n", code_buffer, ascii_buffer); |
| } |
| } |
| |
| /* |
| * If configured to do so, dump memory around *all* registers |
| * for the crashing thread. |
| */ |
| void dump_memory_and_code(const ptrace_context_t* context __attribute((unused)), |
| log_t* log, pid_t tid, bool at_fault) { |
| pt_regs_mips_t r; |
| if(ptrace(PTRACE_GETREGS, tid, 0, &r)) { |
| return; |
| } |
| |
| if (at_fault && DUMP_MEMORY_FOR_ALL_REGISTERS) { |
| static const char REG_NAMES[] = "$0atv0v1a0a1a2a3t0t1t2t3t4t5t6t7s0s1s2s3s4s5s6s7t8t9k0k1gpsps8ra"; |
| |
| for (int reg = 0; reg < 32; reg++) { |
| /* skip uninteresting registers */ |
| if (reg == 0 /* $0 */ |
| || reg == 26 /* $k0 */ |
| || reg == 27 /* $k1 */ |
| || reg == 31 /* $ra (done below) */ |
| ) |
| continue; |
| |
| uintptr_t addr = R(r.regs[reg]); |
| |
| /* |
| * Don't bother if it looks like a small int or ~= null, or if |
| * it's in the kernel area. |
| */ |
| if (addr < 4096 || addr >= 0x80000000) { |
| continue; |
| } |
| |
| _LOG(log, false, "\nmemory near %.2s:\n", ®_NAMES[reg * 2]); |
| dump_memory(log, tid, addr, at_fault); |
| } |
| } |
| |
| unsigned int pc = R(r.cp0_epc); |
| unsigned int ra = R(r.regs[31]); |
| |
| _LOG(log, !at_fault, "\ncode around pc:\n"); |
| dump_memory(log, tid, (uintptr_t)pc, at_fault); |
| |
| if (pc != ra) { |
| _LOG(log, !at_fault, "\ncode around ra:\n"); |
| dump_memory(log, tid, (uintptr_t)ra, at_fault); |
| } |
| } |
| |
| void dump_registers(const ptrace_context_t* context __attribute((unused)), |
| log_t* log, pid_t tid, bool at_fault) |
| { |
| pt_regs_mips_t r; |
| bool only_in_tombstone = !at_fault; |
| |
| if(ptrace(PTRACE_GETREGS, tid, 0, &r)) { |
| _LOG(log, only_in_tombstone, "cannot get registers: %s\n", strerror(errno)); |
| return; |
| } |
| |
| _LOG(log, only_in_tombstone, " zr %08x at %08x v0 %08x v1 %08x\n", |
| R(r.regs[0]), R(r.regs[1]), R(r.regs[2]), R(r.regs[3])); |
| _LOG(log, only_in_tombstone, " a0 %08x a1 %08x a2 %08x a3 %08x\n", |
| R(r.regs[4]), R(r.regs[5]), R(r.regs[6]), R(r.regs[7])); |
| _LOG(log, only_in_tombstone, " t0 %08x t1 %08x t2 %08x t3 %08x\n", |
| R(r.regs[8]), R(r.regs[9]), R(r.regs[10]), R(r.regs[11])); |
| _LOG(log, only_in_tombstone, " t4 %08x t5 %08x t6 %08x t7 %08x\n", |
| R(r.regs[12]), R(r.regs[13]), R(r.regs[14]), R(r.regs[15])); |
| _LOG(log, only_in_tombstone, " s0 %08x s1 %08x s2 %08x s3 %08x\n", |
| R(r.regs[16]), R(r.regs[17]), R(r.regs[18]), R(r.regs[19])); |
| _LOG(log, only_in_tombstone, " s4 %08x s5 %08x s6 %08x s7 %08x\n", |
| R(r.regs[20]), R(r.regs[21]), R(r.regs[22]), R(r.regs[23])); |
| _LOG(log, only_in_tombstone, " t8 %08x t9 %08x k0 %08x k1 %08x\n", |
| R(r.regs[24]), R(r.regs[25]), R(r.regs[26]), R(r.regs[27])); |
| _LOG(log, only_in_tombstone, " gp %08x sp %08x s8 %08x ra %08x\n", |
| R(r.regs[28]), R(r.regs[29]), R(r.regs[30]), R(r.regs[31])); |
| _LOG(log, only_in_tombstone, " hi %08x lo %08x bva %08x epc %08x\n", |
| R(r.hi), R(r.lo), R(r.cp0_badvaddr), R(r.cp0_epc)); |
| } |
