/*--------------------------------------------------------------------*/ /*--- Attaching a debugger. m_debugger.c ---*/ /*--------------------------------------------------------------------*/ /* This file is part of Valgrind, a dynamic binary instrumentation framework. Copyright (C) 2000-2009 Julian Seward jseward@acm.org This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. The GNU General Public License is contained in the file COPYING. */ #include "pub_core_basics.h" #include "pub_core_vki.h" #include "pub_core_threadstate.h" #include "pub_core_xarray.h" #include "pub_core_clientstate.h" #include "pub_core_debugger.h" #include "pub_core_libcbase.h" #include "pub_core_libcprint.h" #include "pub_core_libcproc.h" #include "pub_core_libcsignal.h" #include "pub_core_libcassert.h" #include "pub_core_options.h" #define WIFSTOPPED(status) (((status) & 0xff) == 0x7f) #define WSTOPSIG(status) (((status) & 0xff00) >> 8) static Int ptrace_setregs(Int pid, VexGuestArchState* vex) { #if defined(VGP_x86_linux) struct vki_user_regs_struct regs; VG_(memset)(®s, 0, sizeof(regs)); regs.cs = vex->guest_CS; regs.ss = vex->guest_SS; regs.ds = vex->guest_DS; regs.es = vex->guest_ES; regs.fs = vex->guest_FS; regs.gs = vex->guest_GS; regs.eax = vex->guest_EAX; regs.ebx = vex->guest_EBX; regs.ecx = vex->guest_ECX; regs.edx = vex->guest_EDX; regs.esi = vex->guest_ESI; regs.edi = vex->guest_EDI; regs.ebp = vex->guest_EBP; regs.esp = vex->guest_ESP; regs.eflags = LibVEX_GuestX86_get_eflags(vex); regs.eip = vex->guest_EIP; return VG_(ptrace)(VKI_PTRACE_SETREGS, pid, NULL, ®s); #elif defined(VGP_amd64_linux) struct vki_user_regs_struct regs; VG_(memset)(®s, 0, sizeof(regs)); regs.rax = vex->guest_RAX; regs.rbx = vex->guest_RBX; regs.rcx = vex->guest_RCX; regs.rdx = vex->guest_RDX; regs.rsi = vex->guest_RSI; regs.rdi = vex->guest_RDI; regs.rbp = vex->guest_RBP; regs.rsp = vex->guest_RSP; regs.r8 = vex->guest_R8; regs.r9 = vex->guest_R9; regs.r10 = vex->guest_R10; regs.r11 = vex->guest_R11; regs.r12 = vex->guest_R12; regs.r13 = vex->guest_R13; regs.r14 = vex->guest_R14; regs.r15 = vex->guest_R15; regs.eflags = LibVEX_GuestAMD64_get_rflags(vex); regs.rip = vex->guest_RIP; /* Set %{c,d,e,f,s,g}s and %{fs,gs}_base (whatever those are) to values which don't fail the kernel's sanity checks. I have no idea what these should really be set to. Anyway, mostly it seems that zero is an allowable value, except for %cs and %ss which have to have their lowest 2 bits be 11. See putreg() in linux-2.6.23/arch/x86_64/kernel/ptrace.c for the apparently relevant sanity checks. This fixes #145622. */ regs.cs = 3; regs.ds = 0; regs.es = 0; regs.fs = 0; regs.ss = 3; regs.gs = 0; regs.fs_base = 0; regs.gs_base = 0; return VG_(ptrace)(VKI_PTRACE_SETREGS, pid, NULL, ®s); #elif defined(VGP_ppc32_linux) Int rc = 0; /* apparently the casting to void* is the Right Thing To Do */ rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R0 * 4), (void*)vex->guest_GPR0); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R1 * 4), (void*)vex->guest_GPR1); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R2 * 4), (void*)vex->guest_GPR2); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R3 * 4), (void*)vex->guest_GPR3); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R4 * 4), (void*)vex->guest_GPR4); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R5 * 4), (void*)vex->guest_GPR5); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R6 * 4), (void*)vex->guest_GPR6); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R7 * 4), (void*)vex->guest_GPR7); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R8 * 4), (void*)vex->guest_GPR8); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R9 * 4), (void*)vex->guest_GPR9); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R10 * 4), (void*)vex->guest_GPR10); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R11 * 4), (void*)vex->guest_GPR11); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R12 * 4), (void*)vex->guest_GPR12); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R13 * 4), (void*)vex->guest_GPR13); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R14 * 4), (void*)vex->guest_GPR14); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R15 * 4), (void*)vex->guest_GPR15); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R16 * 4), (void*)vex->guest_GPR16); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R17 * 4), (void*)vex->guest_GPR17); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R18 * 4), (void*)vex->guest_GPR18); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R19 * 4), (void*)vex->guest_GPR19); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R20 * 4), (void*)vex->guest_GPR20); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R21 * 4), (void*)vex->guest_GPR21); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R22 * 4), (void*)vex->guest_GPR22); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R23 * 4), (void*)vex->guest_GPR23); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R24 * 4), (void*)vex->guest_GPR24); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R25 * 4), (void*)vex->guest_GPR25); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R26 * 4), (void*)vex->guest_GPR26); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R27 * 4), (void*)vex->guest_GPR27); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R28 * 4), (void*)vex->guest_GPR28); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R29 * 4), (void*)vex->guest_GPR29); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R30 * 4), (void*)vex->guest_GPR30); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R31 * 4), (void*)vex->guest_GPR31); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_NIP * 4), (void*)vex->guest_CIA); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_CCR * 4), (void*)LibVEX_GuestPPC32_get_CR(vex)); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_LNK * 4), (void*)vex->guest_LR); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_CTR * 4), (void*)vex->guest_CTR); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_XER * 4), (void*)LibVEX_GuestPPC32_get_XER(vex)); return rc; #elif defined(VGP_ppc64_linux) Int rc = 0; /* FRJ: copied nearly verbatim from the ppc32 case. I compared the vki-ppc64-linux.h with its ppc32 counterpart and saw no appreciable differences, other than the registers being 8 bytes instead of 4. No idea why we don't set all of the entries declared in vki_pt_regs, but ppc32 doesn't so there must be a reason. Finally, note that CR and XER are 32 bits even for ppc64 (see libvex_guest_ppc64.h), but the vki_pt_regs struct still gives them 64 bits. */ /* apparently the casting to void* is the Right Thing To Do */ rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R0 * 8), (void*)vex->guest_GPR0); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R1 * 8), (void*)vex->guest_GPR1); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R2 * 8), (void*)vex->guest_GPR2); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R3 * 8), (void*)vex->guest_GPR3); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R4 * 8), (void*)vex->guest_GPR4); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R5 * 8), (void*)vex->guest_GPR5); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R6 * 8), (void*)vex->guest_GPR6); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R7 * 8), (void*)vex->guest_GPR7); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R8 * 8), (void*)vex->guest_GPR8); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R9 * 8), (void*)vex->guest_GPR9); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R10 * 8), (void*)vex->guest_GPR10); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R11 * 8), (void*)vex->guest_GPR11); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R12 * 8), (void*)vex->guest_GPR12); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R13 * 8), (void*)vex->guest_GPR13); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R14 * 8), (void*)vex->guest_GPR14); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R15 * 8), (void*)vex->guest_GPR15); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R16 * 8), (void*)vex->guest_GPR16); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R17 * 8), (void*)vex->guest_GPR17); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R18 * 8), (void*)vex->guest_GPR18); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R19 * 8), (void*)vex->guest_GPR19); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R20 * 8), (void*)vex->guest_GPR20); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R21 * 8), (void*)vex->guest_GPR21); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R22 * 8), (void*)vex->guest_GPR22); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R23 * 8), (void*)vex->guest_GPR23); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R24 * 8), (void*)vex->guest_GPR24); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R25 * 8), (void*)vex->guest_GPR25); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R26 * 8), (void*)vex->guest_GPR26); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R27 * 8), (void*)vex->guest_GPR27); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R28 * 8), (void*)vex->guest_GPR28); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R29 * 8), (void*)vex->guest_GPR29); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R30 * 8), (void*)vex->guest_GPR30); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_R31 * 8), (void*)vex->guest_GPR31); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_NIP * 8), (void*)vex->guest_CIA); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_CCR * 8), (void*)(long)LibVEX_GuestPPC64_get_CR(vex)); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_LNK * 8), (void*)vex->guest_LR); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_CTR * 8), (void*)vex->guest_CTR); rc |= VG_(ptrace)(VKI_PTRACE_POKEUSR, pid, (void*)(VKI_PT_XER * 8), (void*)(long)LibVEX_GuestPPC64_get_XER(vex)); return rc; #elif defined(VGP_ppc32_aix5) I_die_here; #elif defined(VGP_ppc64_aix5) I_die_here; #elif defined(VGP_x86_darwin) I_die_here; #elif defined(VGP_amd64_darwin) I_die_here; #else # error Unknown arch #endif } /* Start debugger and get it to attach to this process. Called if the user requests this service after an error has been shown, so she can poke around and look at parameters, memory, etc. You can't meaningfully get the debugger to continue the program, though; to continue, quit the debugger. */ void VG_(start_debugger) ( ThreadId tid ) { # define N_BUF 4096 Int pid, rc; pid = VG_(fork)(); if (pid == 0) { /* child */ rc = VG_(ptrace)(VKI_PTRACE_TRACEME, 0, NULL, NULL); vg_assert(rc == 0); rc = VG_(kill)(VG_(getpid)(), VKI_SIGSTOP); vg_assert(rc == 0); } else if (pid > 0) { /* parent */ Int status; Int res; if ((res = VG_(waitpid)(pid, &status, 0)) == pid && WIFSTOPPED(status) && WSTOPSIG(status) == VKI_SIGSTOP && ptrace_setregs(pid, &(VG_(threads)[tid].arch.vex)) == 0 && VG_(kill)(pid, VKI_SIGSTOP) == 0 && VG_(ptrace)(VKI_PTRACE_DETACH, pid, NULL, 0) == 0) { Char pidbuf[15]; Char file[50]; Char buf[N_BUF]; Char *bufptr; Char *cmdptr; VG_(sprintf)(pidbuf, "%d", pid); VG_(sprintf)(file, "/proc/%d/fd/%d", pid, VG_(cl_exec_fd)); bufptr = buf; cmdptr = VG_(clo_db_command); while (*cmdptr) { /* each iteration can advance bufptr by at most the length of file[], so the following assertion is generously over-paranoid. */ vg_assert(bufptr - buf < N_BUF-15-50-10/*paranoia*/); switch (*cmdptr) { case '%': switch (*++cmdptr) { case 'f': VG_(memcpy)(bufptr, file, VG_(strlen)(file)); bufptr += VG_(strlen)(file); cmdptr++; break; case 'p': VG_(memcpy)(bufptr, pidbuf, VG_(strlen)(pidbuf)); bufptr += VG_(strlen)(pidbuf); cmdptr++; break; default: *bufptr++ = *cmdptr++; break; } break; default: *bufptr++ = *cmdptr++; break; } vg_assert(bufptr - buf < N_BUF-15-50-10/*paranoia*/); } *bufptr++ = '\0'; VG_(message)(Vg_UserMsg, "starting debugger with cmd: %s", buf); res = VG_(system)(buf); if (res == 0) { VG_(message)(Vg_UserMsg, ""); VG_(message)(Vg_UserMsg, "Debugger has detached. Valgrind regains control." " We continue."); } else { VG_(message)(Vg_UserMsg, "Warning: Debugger attach failed! (sys_system)"); VG_(message)(Vg_UserMsg, ""); } } else { VG_(message)(Vg_UserMsg, "Warning: Debugger attach failed! (ptrace problem?)"); VG_(message)(Vg_UserMsg, ""); } VG_(kill)(pid, VKI_SIGKILL); VG_(waitpid)(pid, &status, 0); } # undef N_BUF } /*--------------------------------------------------------------------*/ /*--- end ---*/ /*--------------------------------------------------------------------*/