c73a3f16f8
This patch is rearranging code a bit to add WatchpointResources to
Process. A WatchpointResource is meant to represent a hardware
watchpoint register in the inferior process. It has an address, a size,
a type, and a list of Watchpoints that are using this
WatchpointResource.
This current patch doesn't add any of the features of
WatchpointResources that make them interesting -- a user asking to watch
a 24 byte object could watch this with three 8 byte WatchpointResources.
Or a Watchpoint on 1 byte at 0x1002 and a second watchpoint on 1 byte at
0x1003, these must both be served by a single WatchpointResource on that
doubleword at 0x1000 on a 64-bit target, if two hardware watchpoint
registers were used to track these separately, one of them may not be
hit. Or if you have one Watchpoint on a variable with a condition set,
and another Watchpoint on that same variable with a command defined or
different condition, or ignorecount, both of those Watchpoints need to
evaluate their criteria/commands when their WatchpointResource has been
hit.
There's a bit of code movement to rearrange things in the direction I'll
need for implementing this feature, so I want to start with reviewing &
landing this mostly NFC patch and we can focus on the algorithmic
choices about how WatchpointResources are shared and handled as they're
triggeed, separately.
This patch also stops printing "Watchpoint <n> hit: old value: <x>, new
vlaue: <y>" for Read watchpoints. I could make an argument for print
"Watchpoint <n> hit: current value <x>" but the current output doesn't
make any sense, and the user can print the value if they are
particularly interested. Read watchpoints are used primarily to
understand what code is reading a variable.
This patch adds more fallbacks for how to print the objects being
watched if we have types, instead of assuming they are all integral
values, so a struct will print its elements. As large watchpoints are
added, we'll be doing a lot more of those.
To track the WatchpointSP in the WatchpointResources, I changed the
internal API which took a WatchpointSP and devolved it to a Watchpoint*,
which meant touching several different Process files. I removed the
watchpoint code in ProcessKDP which only reported that watchpoints
aren't supported, the base class does that already.
I haven't yet changed how we receive a watchpoint to identify the
WatchpointResource responsible for the trigger, and identify all
Watchpoints that are using this Resource to evaluate their conditions
etc. This is the same work that a BreakpointSite needs to do when it has
been tiggered, where multiple Breakpoints may be at the same address.
There is not yet any printing of the Resources that a Watchpoint is
implemented in terms of ("watchpoint list", or
SBWatchpoint::GetDescription).
"watchpoint set var" and "watchpoint set expression" take a size
argument which was previously 1, 2, 4, or 8 (an enum). I've changed this
to an unsigned int. Most hardware implementations can only watch 1, 2,
4, 8 byte ranges, but with Resources we'll allow a user to ask for
different sized watchpoints and set them in hardware-expressble terms
soon.
I've annotated areas where I know there is work still needed with
LWP_TODO that I'll be working on once this is landed.
I've tested this on aarch64 macOS, aarch64 Linux, and Intel macOS.
https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116
(cherry picked from commit fc6b72523f)
832 lines
27 KiB
C++
832 lines
27 KiB
C++
//===-- StopInfoMachException.cpp -----------------------------------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "StopInfoMachException.h"
|
|
|
|
#include "lldb/lldb-forward.h"
|
|
|
|
#if defined(__APPLE__)
|
|
// Needed for the EXC_RESOURCE interpretation macros
|
|
#include <kern/exc_resource.h>
|
|
#endif
|
|
|
|
#include "lldb/Breakpoint/Watchpoint.h"
|
|
#include "lldb/Symbol/Symbol.h"
|
|
#include "lldb/Target/ABI.h"
|
|
#include "lldb/Target/DynamicLoader.h"
|
|
#include "lldb/Target/ExecutionContext.h"
|
|
#include "lldb/Target/Process.h"
|
|
#include "lldb/Target/RegisterContext.h"
|
|
#include "lldb/Target/Target.h"
|
|
#include "lldb/Target/Thread.h"
|
|
#include "lldb/Target/ThreadPlan.h"
|
|
#include "lldb/Target/UnixSignals.h"
|
|
#include "lldb/Utility/StreamString.h"
|
|
#include <optional>
|
|
|
|
using namespace lldb;
|
|
using namespace lldb_private;
|
|
|
|
/// Information about a pointer-authentication related instruction.
|
|
struct PtrauthInstructionInfo {
|
|
bool IsAuthenticated;
|
|
bool IsLoad;
|
|
bool DoesBranch;
|
|
};
|
|
|
|
/// Get any pointer-authentication related information about the instruction
|
|
/// at address \p at_addr.
|
|
static std::optional<PtrauthInstructionInfo>
|
|
GetPtrauthInstructionInfo(Target &target, const ArchSpec &arch,
|
|
const Address &at_addr) {
|
|
const char *plugin_name = nullptr;
|
|
const char *flavor = nullptr;
|
|
AddressRange range_bounds(at_addr, 4);
|
|
const bool prefer_file_cache = true;
|
|
DisassemblerSP disassembler_sp = Disassembler::DisassembleRange(
|
|
arch, plugin_name, flavor, target, range_bounds, prefer_file_cache);
|
|
if (!disassembler_sp)
|
|
return std::nullopt;
|
|
|
|
InstructionList &insn_list = disassembler_sp->GetInstructionList();
|
|
InstructionSP insn = insn_list.GetInstructionAtIndex(0);
|
|
if (!insn)
|
|
return std::nullopt;
|
|
|
|
return PtrauthInstructionInfo{insn->IsAuthenticated(), insn->IsLoad(),
|
|
insn->DoesBranch()};
|
|
}
|
|
|
|
/// Describe the load address of \p addr using the format filename:line:col.
|
|
static void DescribeAddressBriefly(Stream &strm, const Address &addr,
|
|
Target &target) {
|
|
strm.Printf("at address=0x%" PRIx64, addr.GetLoadAddress(&target));
|
|
StreamString s;
|
|
if (addr.GetDescription(s, target, eDescriptionLevelBrief))
|
|
strm.Printf(" %s", s.GetString().data());
|
|
strm.Printf(".\n");
|
|
}
|
|
|
|
bool StopInfoMachException::DeterminePtrauthFailure(ExecutionContext &exe_ctx) {
|
|
bool IsBreakpoint = m_value == 6; // EXC_BREAKPOINT
|
|
bool IsBadAccess = m_value == 1; // EXC_BAD_ACCESS
|
|
if (!IsBreakpoint && !IsBadAccess)
|
|
return false;
|
|
|
|
// Check that we have a live process.
|
|
if (!exe_ctx.HasProcessScope() || !exe_ctx.HasThreadScope() ||
|
|
!exe_ctx.HasTargetScope())
|
|
return false;
|
|
|
|
Thread &thread = *exe_ctx.GetThreadPtr();
|
|
StackFrameSP current_frame = thread.GetStackFrameAtIndex(0);
|
|
if (!current_frame)
|
|
return false;
|
|
|
|
Target &target = *exe_ctx.GetTargetPtr();
|
|
Process &process = *exe_ctx.GetProcessPtr();
|
|
ABISP abi_sp = process.GetABI();
|
|
const ArchSpec &arch = target.GetArchitecture();
|
|
assert(abi_sp && "Missing ABI info");
|
|
|
|
// Check for a ptrauth-enabled target.
|
|
const bool ptrauth_enabled_target =
|
|
arch.GetCore() == ArchSpec::eCore_arm_arm64e;
|
|
if (!ptrauth_enabled_target)
|
|
return false;
|
|
|
|
// Set up a stream we can write a diagnostic into.
|
|
StreamString strm;
|
|
auto emit_ptrauth_prologue = [&](uint64_t at_address) {
|
|
strm.Printf("EXC_BAD_ACCESS (code=%" PRIu64 ", address=0x%" PRIx64 ")\n",
|
|
m_exc_code, at_address);
|
|
strm.Printf("Note: Possible pointer authentication failure detected.\n");
|
|
};
|
|
|
|
// Check if we have a "brk 0xc47x" trap, where the value that failed to
|
|
// authenticate is in x16.
|
|
Address current_address = current_frame->GetFrameCodeAddress();
|
|
if (IsBreakpoint) {
|
|
RegisterContext *reg_ctx = exe_ctx.GetRegisterContext();
|
|
if (!reg_ctx)
|
|
return false;
|
|
|
|
const RegisterInfo *X16Info = reg_ctx->GetRegisterInfoByName("x16");
|
|
RegisterValue X16Val;
|
|
if (!reg_ctx->ReadRegister(X16Info, X16Val))
|
|
return false;
|
|
uint64_t bad_address = X16Val.GetAsUInt64();
|
|
|
|
uint64_t fixed_bad_address = abi_sp->FixCodeAddress(bad_address);
|
|
Address brk_address;
|
|
if (!target.ResolveLoadAddress(fixed_bad_address, brk_address))
|
|
return false;
|
|
|
|
auto brk_ptrauth_info =
|
|
GetPtrauthInstructionInfo(target, arch, current_address);
|
|
if (brk_ptrauth_info && brk_ptrauth_info->IsAuthenticated) {
|
|
emit_ptrauth_prologue(bad_address);
|
|
strm.Printf("Found value that failed to authenticate ");
|
|
DescribeAddressBriefly(strm, brk_address, target);
|
|
m_description = std::string(strm.GetString());
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
assert(IsBadAccess && "Handle EXC_BAD_ACCESS only after this point");
|
|
|
|
// Check that we have the "bad address" from an EXC_BAD_ACCESS.
|
|
if (m_exc_data_count < 2)
|
|
return false;
|
|
|
|
// Ok, we know the Target is valid and that it describes a ptrauth-enabled
|
|
// device. Now, we need to determine whether this exception was caused by a
|
|
// ptrauth failure.
|
|
|
|
uint64_t bad_address = m_exc_subcode;
|
|
uint64_t fixed_bad_address = abi_sp->FixCodeAddress(bad_address);
|
|
uint64_t current_pc = current_address.GetLoadAddress(&target);
|
|
|
|
// Detect: LDRAA, LDRAB (Load Register, with pointer authentication).
|
|
//
|
|
// If an authenticated load results in an exception, the instruction at the
|
|
// current PC should be one of LDRAx.
|
|
if (bad_address != current_pc && fixed_bad_address != current_pc) {
|
|
auto ptrauth_info =
|
|
GetPtrauthInstructionInfo(target, arch, current_address);
|
|
if (ptrauth_info && ptrauth_info->IsAuthenticated && ptrauth_info->IsLoad) {
|
|
emit_ptrauth_prologue(bad_address);
|
|
strm.Printf("Found authenticated load instruction ");
|
|
DescribeAddressBriefly(strm, current_address, target);
|
|
m_description = std::string(strm.GetString());
|
|
return true;
|
|
}
|
|
}
|
|
|
|
// Detect: BLRAA, BLRAAZ, BLRAB, BLRABZ (Branch with Link to Register, with
|
|
// pointer authentication).
|
|
//
|
|
// TODO: Detect: BRAA, BRAAZ, BRAB, BRABZ (Branch to Register, with pointer
|
|
// authentication). At a minimum, this requires call site info support for
|
|
// indirect calls.
|
|
//
|
|
// If an authenticated call or tail call results in an exception, stripping
|
|
// the bad address should give the current PC, which points to the address
|
|
// we tried to branch to.
|
|
if (bad_address != current_pc && fixed_bad_address == current_pc) {
|
|
if (StackFrameSP parent_frame = thread.GetStackFrameAtIndex(1)) {
|
|
addr_t return_pc =
|
|
parent_frame->GetFrameCodeAddress().GetLoadAddress(&target);
|
|
Address blr_address;
|
|
if (!target.ResolveLoadAddress(return_pc - 4, blr_address))
|
|
return false;
|
|
|
|
auto blr_ptrauth_info =
|
|
GetPtrauthInstructionInfo(target, arch, blr_address);
|
|
if (blr_ptrauth_info && blr_ptrauth_info->IsAuthenticated &&
|
|
blr_ptrauth_info->DoesBranch) {
|
|
emit_ptrauth_prologue(bad_address);
|
|
strm.Printf("Found authenticated indirect branch ");
|
|
DescribeAddressBriefly(strm, blr_address, target);
|
|
m_description = std::string(strm.GetString());
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
// TODO: Detect: RETAA, RETAB (Return from subroutine, with pointer
|
|
// authentication).
|
|
//
|
|
// Is there a motivating, non-malicious code snippet that corrupts LR?
|
|
|
|
return false;
|
|
}
|
|
|
|
const char *StopInfoMachException::GetDescription() {
|
|
if (!m_description.empty())
|
|
return m_description.c_str();
|
|
if (GetValue() == eStopReasonInvalid)
|
|
return "invalid stop reason!";
|
|
|
|
ExecutionContext exe_ctx(m_thread_wp.lock());
|
|
Target *target = exe_ctx.GetTargetPtr();
|
|
const llvm::Triple::ArchType cpu =
|
|
target ? target->GetArchitecture().GetMachine()
|
|
: llvm::Triple::UnknownArch;
|
|
|
|
const char *exc_desc = nullptr;
|
|
const char *code_label = "code";
|
|
const char *code_desc = nullptr;
|
|
const char *subcode_label = "subcode";
|
|
const char *subcode_desc = nullptr;
|
|
|
|
#if defined(__APPLE__)
|
|
char code_desc_buf[32];
|
|
char subcode_desc_buf[32];
|
|
#endif
|
|
|
|
switch (m_value) {
|
|
case 1: // EXC_BAD_ACCESS
|
|
exc_desc = "EXC_BAD_ACCESS";
|
|
subcode_label = "address";
|
|
switch (cpu) {
|
|
case llvm::Triple::x86:
|
|
case llvm::Triple::x86_64:
|
|
switch (m_exc_code) {
|
|
case 0xd:
|
|
code_desc = "EXC_I386_GPFLT";
|
|
m_exc_data_count = 1;
|
|
break;
|
|
}
|
|
break;
|
|
case llvm::Triple::arm:
|
|
case llvm::Triple::thumb:
|
|
switch (m_exc_code) {
|
|
case 0x101:
|
|
code_desc = "EXC_ARM_DA_ALIGN";
|
|
break;
|
|
case 0x102:
|
|
code_desc = "EXC_ARM_DA_DEBUG";
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case llvm::Triple::aarch64:
|
|
if (DeterminePtrauthFailure(exe_ctx))
|
|
return m_description.c_str();
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case 2: // EXC_BAD_INSTRUCTION
|
|
exc_desc = "EXC_BAD_INSTRUCTION";
|
|
switch (cpu) {
|
|
case llvm::Triple::x86:
|
|
case llvm::Triple::x86_64:
|
|
if (m_exc_code == 1)
|
|
code_desc = "EXC_I386_INVOP";
|
|
break;
|
|
|
|
case llvm::Triple::arm:
|
|
case llvm::Triple::thumb:
|
|
if (m_exc_code == 1)
|
|
code_desc = "EXC_ARM_UNDEFINED";
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case 3: // EXC_ARITHMETIC
|
|
exc_desc = "EXC_ARITHMETIC";
|
|
switch (cpu) {
|
|
case llvm::Triple::x86:
|
|
case llvm::Triple::x86_64:
|
|
switch (m_exc_code) {
|
|
case 1:
|
|
code_desc = "EXC_I386_DIV";
|
|
break;
|
|
case 2:
|
|
code_desc = "EXC_I386_INTO";
|
|
break;
|
|
case 3:
|
|
code_desc = "EXC_I386_NOEXT";
|
|
break;
|
|
case 4:
|
|
code_desc = "EXC_I386_EXTOVR";
|
|
break;
|
|
case 5:
|
|
code_desc = "EXC_I386_EXTERR";
|
|
break;
|
|
case 6:
|
|
code_desc = "EXC_I386_EMERR";
|
|
break;
|
|
case 7:
|
|
code_desc = "EXC_I386_BOUND";
|
|
break;
|
|
case 8:
|
|
code_desc = "EXC_I386_SSEEXTERR";
|
|
break;
|
|
}
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case 4: // EXC_EMULATION
|
|
exc_desc = "EXC_EMULATION";
|
|
break;
|
|
|
|
case 5: // EXC_SOFTWARE
|
|
exc_desc = "EXC_SOFTWARE";
|
|
if (m_exc_code == 0x10003) {
|
|
subcode_desc = "EXC_SOFT_SIGNAL";
|
|
subcode_label = "signo";
|
|
}
|
|
break;
|
|
|
|
case 6: // EXC_BREAKPOINT
|
|
{
|
|
exc_desc = "EXC_BREAKPOINT";
|
|
switch (cpu) {
|
|
case llvm::Triple::x86:
|
|
case llvm::Triple::x86_64:
|
|
switch (m_exc_code) {
|
|
case 1:
|
|
code_desc = "EXC_I386_SGL";
|
|
break;
|
|
case 2:
|
|
code_desc = "EXC_I386_BPT";
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case llvm::Triple::arm:
|
|
case llvm::Triple::thumb:
|
|
switch (m_exc_code) {
|
|
case 0x101:
|
|
code_desc = "EXC_ARM_DA_ALIGN";
|
|
break;
|
|
case 0x102:
|
|
code_desc = "EXC_ARM_DA_DEBUG";
|
|
break;
|
|
case 1:
|
|
code_desc = "EXC_ARM_BREAKPOINT";
|
|
break;
|
|
// FIXME temporary workaround, exc_code 0 does not really mean
|
|
// EXC_ARM_BREAKPOINT
|
|
case 0:
|
|
code_desc = "EXC_ARM_BREAKPOINT";
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case llvm::Triple::aarch64:
|
|
if (DeterminePtrauthFailure(exe_ctx))
|
|
return m_description.c_str();
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
} break;
|
|
|
|
case 7:
|
|
exc_desc = "EXC_SYSCALL";
|
|
break;
|
|
|
|
case 8:
|
|
exc_desc = "EXC_MACH_SYSCALL";
|
|
break;
|
|
|
|
case 9:
|
|
exc_desc = "EXC_RPC_ALERT";
|
|
break;
|
|
|
|
case 10:
|
|
exc_desc = "EXC_CRASH";
|
|
break;
|
|
case 11:
|
|
exc_desc = "EXC_RESOURCE";
|
|
#if defined(__APPLE__)
|
|
{
|
|
int resource_type = EXC_RESOURCE_DECODE_RESOURCE_TYPE(m_exc_code);
|
|
|
|
code_label = "limit";
|
|
code_desc = code_desc_buf;
|
|
subcode_label = "observed";
|
|
subcode_desc = subcode_desc_buf;
|
|
|
|
switch (resource_type) {
|
|
case RESOURCE_TYPE_CPU:
|
|
exc_desc =
|
|
"EXC_RESOURCE (RESOURCE_TYPE_CPU: CPU usage monitor tripped)";
|
|
snprintf(code_desc_buf, sizeof(code_desc_buf), "%d%%",
|
|
(int)EXC_RESOURCE_CPUMONITOR_DECODE_PERCENTAGE(m_exc_code));
|
|
snprintf(subcode_desc_buf, sizeof(subcode_desc_buf), "%d%%",
|
|
(int)EXC_RESOURCE_CPUMONITOR_DECODE_PERCENTAGE_OBSERVED(
|
|
m_exc_subcode));
|
|
break;
|
|
case RESOURCE_TYPE_WAKEUPS:
|
|
exc_desc = "EXC_RESOURCE (RESOURCE_TYPE_WAKEUPS: idle wakeups monitor "
|
|
"tripped)";
|
|
snprintf(
|
|
code_desc_buf, sizeof(code_desc_buf), "%d w/s",
|
|
(int)EXC_RESOURCE_CPUMONITOR_DECODE_WAKEUPS_PERMITTED(m_exc_code));
|
|
snprintf(subcode_desc_buf, sizeof(subcode_desc_buf), "%d w/s",
|
|
(int)EXC_RESOURCE_CPUMONITOR_DECODE_WAKEUPS_OBSERVED(
|
|
m_exc_subcode));
|
|
break;
|
|
case RESOURCE_TYPE_MEMORY:
|
|
exc_desc = "EXC_RESOURCE (RESOURCE_TYPE_MEMORY: high watermark memory "
|
|
"limit exceeded)";
|
|
snprintf(code_desc_buf, sizeof(code_desc_buf), "%d MB",
|
|
(int)EXC_RESOURCE_HWM_DECODE_LIMIT(m_exc_code));
|
|
subcode_desc = nullptr;
|
|
subcode_label = nullptr;
|
|
break;
|
|
#if defined(RESOURCE_TYPE_IO)
|
|
// RESOURCE_TYPE_IO is introduced in macOS SDK 10.12.
|
|
case RESOURCE_TYPE_IO:
|
|
exc_desc = "EXC_RESOURCE RESOURCE_TYPE_IO";
|
|
snprintf(code_desc_buf, sizeof(code_desc_buf), "%d MB",
|
|
(int)EXC_RESOURCE_IO_DECODE_LIMIT(m_exc_code));
|
|
snprintf(subcode_desc_buf, sizeof(subcode_desc_buf), "%d MB",
|
|
(int)EXC_RESOURCE_IO_OBSERVED(m_exc_subcode));
|
|
;
|
|
break;
|
|
#endif
|
|
}
|
|
}
|
|
#endif
|
|
break;
|
|
case 12:
|
|
exc_desc = "EXC_GUARD";
|
|
break;
|
|
}
|
|
|
|
StreamString strm;
|
|
|
|
if (exc_desc)
|
|
strm.PutCString(exc_desc);
|
|
else
|
|
strm.Printf("EXC_??? (%" PRIu64 ")", m_value);
|
|
|
|
if (m_exc_data_count >= 1) {
|
|
if (code_desc)
|
|
strm.Printf(" (%s=%s", code_label, code_desc);
|
|
else
|
|
strm.Printf(" (%s=%" PRIu64, code_label, m_exc_code);
|
|
}
|
|
|
|
if (m_exc_data_count >= 2) {
|
|
if (subcode_label && subcode_desc)
|
|
strm.Printf(", %s=%s", subcode_label, subcode_desc);
|
|
else if (subcode_label)
|
|
strm.Printf(", %s=0x%" PRIx64, subcode_label, m_exc_subcode);
|
|
}
|
|
|
|
if (m_exc_data_count > 0)
|
|
strm.PutChar(')');
|
|
|
|
m_description = std::string(strm.GetString());
|
|
return m_description.c_str();
|
|
}
|
|
|
|
static StopInfoSP GetStopInfoForHardwareBP(Thread &thread, Target *target,
|
|
uint32_t exc_data_count,
|
|
uint64_t exc_sub_code,
|
|
uint64_t exc_sub_sub_code) {
|
|
// Try hardware watchpoint.
|
|
if (target) {
|
|
// LWP_TODO: We need to find the WatchpointResource that matches
|
|
// the address, and evaluate its Watchpoints.
|
|
|
|
// The exc_sub_code indicates the data break address.
|
|
lldb::WatchpointSP wp_sp =
|
|
target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
|
|
if (wp_sp && wp_sp->IsEnabled()) {
|
|
return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
|
|
}
|
|
}
|
|
|
|
// Try hardware breakpoint.
|
|
ProcessSP process_sp(thread.GetProcess());
|
|
if (process_sp) {
|
|
// The exc_sub_code indicates the data break address.
|
|
lldb::BreakpointSiteSP bp_sp =
|
|
process_sp->GetBreakpointSiteList().FindByAddress(
|
|
(lldb::addr_t)exc_sub_code);
|
|
if (bp_sp && bp_sp->IsEnabled()) {
|
|
return StopInfo::CreateStopReasonWithBreakpointSiteID(thread,
|
|
bp_sp->GetID());
|
|
}
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
#if defined(__APPLE__)
|
|
const char *
|
|
StopInfoMachException::MachException::Name(exception_type_t exc_type) {
|
|
switch (exc_type) {
|
|
case EXC_BAD_ACCESS:
|
|
return "EXC_BAD_ACCESS";
|
|
case EXC_BAD_INSTRUCTION:
|
|
return "EXC_BAD_INSTRUCTION";
|
|
case EXC_ARITHMETIC:
|
|
return "EXC_ARITHMETIC";
|
|
case EXC_EMULATION:
|
|
return "EXC_EMULATION";
|
|
case EXC_SOFTWARE:
|
|
return "EXC_SOFTWARE";
|
|
case EXC_BREAKPOINT:
|
|
return "EXC_BREAKPOINT";
|
|
case EXC_SYSCALL:
|
|
return "EXC_SYSCALL";
|
|
case EXC_MACH_SYSCALL:
|
|
return "EXC_MACH_SYSCALL";
|
|
case EXC_RPC_ALERT:
|
|
return "EXC_RPC_ALERT";
|
|
#ifdef EXC_CRASH
|
|
case EXC_CRASH:
|
|
return "EXC_CRASH";
|
|
#endif
|
|
case EXC_RESOURCE:
|
|
return "EXC_RESOURCE";
|
|
#ifdef EXC_GUARD
|
|
case EXC_GUARD:
|
|
return "EXC_GUARD";
|
|
#endif
|
|
#ifdef EXC_CORPSE_NOTIFY
|
|
case EXC_CORPSE_NOTIFY:
|
|
return "EXC_CORPSE_NOTIFY";
|
|
#endif
|
|
#ifdef EXC_CORPSE_VARIANT_BIT
|
|
case EXC_CORPSE_VARIANT_BIT:
|
|
return "EXC_CORPSE_VARIANT_BIT";
|
|
#endif
|
|
default:
|
|
break;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
std::optional<exception_type_t>
|
|
StopInfoMachException::MachException::ExceptionCode(const char *name) {
|
|
return llvm::StringSwitch<std::optional<exception_type_t>>(name)
|
|
.Case("EXC_BAD_ACCESS", EXC_BAD_ACCESS)
|
|
.Case("EXC_BAD_INSTRUCTION", EXC_BAD_INSTRUCTION)
|
|
.Case("EXC_ARITHMETIC", EXC_ARITHMETIC)
|
|
.Case("EXC_EMULATION", EXC_EMULATION)
|
|
.Case("EXC_SOFTWARE", EXC_SOFTWARE)
|
|
.Case("EXC_BREAKPOINT", EXC_BREAKPOINT)
|
|
.Case("EXC_SYSCALL", EXC_SYSCALL)
|
|
.Case("EXC_MACH_SYSCALL", EXC_MACH_SYSCALL)
|
|
.Case("EXC_RPC_ALERT", EXC_RPC_ALERT)
|
|
#ifdef EXC_CRASH
|
|
.Case("EXC_CRASH", EXC_CRASH)
|
|
#endif
|
|
.Case("EXC_RESOURCE", EXC_RESOURCE)
|
|
#ifdef EXC_GUARD
|
|
.Case("EXC_GUARD", EXC_GUARD)
|
|
#endif
|
|
#ifdef EXC_CORPSE_NOTIFY
|
|
.Case("EXC_CORPSE_NOTIFY", EXC_CORPSE_NOTIFY)
|
|
#endif
|
|
.Default(std::nullopt);
|
|
}
|
|
#endif
|
|
|
|
StopInfoSP StopInfoMachException::CreateStopReasonWithMachException(
|
|
Thread &thread, uint32_t exc_type, uint32_t exc_data_count,
|
|
uint64_t exc_code, uint64_t exc_sub_code, uint64_t exc_sub_sub_code,
|
|
bool pc_already_adjusted, bool adjust_pc_if_needed) {
|
|
if (exc_type == 0)
|
|
return StopInfoSP();
|
|
|
|
uint32_t pc_decrement = 0;
|
|
ExecutionContext exe_ctx(thread.shared_from_this());
|
|
Target *target = exe_ctx.GetTargetPtr();
|
|
const llvm::Triple::ArchType cpu =
|
|
target ? target->GetArchitecture().GetMachine()
|
|
: llvm::Triple::UnknownArch;
|
|
|
|
switch (exc_type) {
|
|
case 1: // EXC_BAD_ACCESS
|
|
case 2: // EXC_BAD_INSTRUCTION
|
|
case 3: // EXC_ARITHMETIC
|
|
case 4: // EXC_EMULATION
|
|
break;
|
|
|
|
case 5: // EXC_SOFTWARE
|
|
if (exc_code == 0x10003) // EXC_SOFT_SIGNAL
|
|
{
|
|
if (exc_sub_code == 5) {
|
|
// On MacOSX, a SIGTRAP can signify that a process has called exec,
|
|
// so we should check with our dynamic loader to verify.
|
|
ProcessSP process_sp(thread.GetProcess());
|
|
if (process_sp) {
|
|
DynamicLoader *dynamic_loader = process_sp->GetDynamicLoader();
|
|
if (dynamic_loader && dynamic_loader->ProcessDidExec()) {
|
|
// The program was re-exec'ed
|
|
return StopInfo::CreateStopReasonWithExec(thread);
|
|
}
|
|
}
|
|
}
|
|
return StopInfo::CreateStopReasonWithSignal(thread, exc_sub_code);
|
|
}
|
|
break;
|
|
|
|
case 6: // EXC_BREAKPOINT
|
|
{
|
|
bool is_actual_breakpoint = false;
|
|
bool is_trace_if_actual_breakpoint_missing = false;
|
|
switch (cpu) {
|
|
case llvm::Triple::x86:
|
|
case llvm::Triple::x86_64:
|
|
if (exc_code == 1) // EXC_I386_SGL
|
|
{
|
|
if (!exc_sub_code) {
|
|
// This looks like a plain trap.
|
|
// Have to check if there is a breakpoint here as well. When you
|
|
// single-step onto a trap, the single step stops you not to trap.
|
|
// Since we also do that check below, let's just use that logic.
|
|
is_actual_breakpoint = true;
|
|
is_trace_if_actual_breakpoint_missing = true;
|
|
} else {
|
|
if (StopInfoSP stop_info =
|
|
GetStopInfoForHardwareBP(thread, target, exc_data_count,
|
|
exc_sub_code, exc_sub_sub_code))
|
|
return stop_info;
|
|
}
|
|
} else if (exc_code == 2 || // EXC_I386_BPT
|
|
exc_code == 3) // EXC_I386_BPTFLT
|
|
{
|
|
// KDP returns EXC_I386_BPTFLT for trace breakpoints
|
|
if (exc_code == 3)
|
|
is_trace_if_actual_breakpoint_missing = true;
|
|
|
|
is_actual_breakpoint = true;
|
|
if (!pc_already_adjusted)
|
|
pc_decrement = 1;
|
|
}
|
|
break;
|
|
|
|
case llvm::Triple::arm:
|
|
case llvm::Triple::thumb:
|
|
if (exc_code == 0x102) // EXC_ARM_DA_DEBUG
|
|
{
|
|
// LWP_TODO: We need to find the WatchpointResource that matches
|
|
// the address, and evaluate its Watchpoints.
|
|
|
|
// It's a watchpoint, then, if the exc_sub_code indicates a
|
|
// known/enabled data break address from our watchpoint list.
|
|
lldb::WatchpointSP wp_sp;
|
|
if (target)
|
|
wp_sp = target->GetWatchpointList().FindByAddress(
|
|
(lldb::addr_t)exc_sub_code);
|
|
if (wp_sp && wp_sp->IsEnabled()) {
|
|
return StopInfo::CreateStopReasonWithWatchpointID(thread,
|
|
wp_sp->GetID());
|
|
} else {
|
|
is_actual_breakpoint = true;
|
|
is_trace_if_actual_breakpoint_missing = true;
|
|
}
|
|
} else if (exc_code == 1) // EXC_ARM_BREAKPOINT
|
|
{
|
|
is_actual_breakpoint = true;
|
|
is_trace_if_actual_breakpoint_missing = true;
|
|
} else if (exc_code == 0) // FIXME not EXC_ARM_BREAKPOINT but a kernel
|
|
// is currently returning this so accept it
|
|
// as indicating a breakpoint until the
|
|
// kernel is fixed
|
|
{
|
|
is_actual_breakpoint = true;
|
|
is_trace_if_actual_breakpoint_missing = true;
|
|
}
|
|
break;
|
|
|
|
case llvm::Triple::aarch64_32:
|
|
case llvm::Triple::aarch64: {
|
|
// xnu describes three things with type EXC_BREAKPOINT:
|
|
//
|
|
// exc_code 0x102 [EXC_ARM_DA_DEBUG], exc_sub_code addr-of-insn
|
|
// Watchpoint access. exc_sub_code is the address of the
|
|
// instruction which trigged the watchpoint trap.
|
|
// debugserver may add the watchpoint number that was triggered
|
|
// in exc_sub_sub_code.
|
|
//
|
|
// exc_code 1 [EXC_ARM_BREAKPOINT], exc_sub_code 0
|
|
// Instruction step has completed.
|
|
//
|
|
// exc_code 1 [EXC_ARM_BREAKPOINT], exc_sub_code address-of-instruction
|
|
// Software breakpoint instruction executed.
|
|
|
|
if (exc_code == 1 && exc_sub_code == 0) // EXC_ARM_BREAKPOINT
|
|
{
|
|
// This is hit when we single instruction step aka MDSCR_EL1 SS bit 0
|
|
// is set
|
|
is_actual_breakpoint = true;
|
|
is_trace_if_actual_breakpoint_missing = true;
|
|
#ifndef NDEBUG
|
|
if (thread.GetTemporaryResumeState() != eStateStepping) {
|
|
StreamString s;
|
|
s.Printf("CreateStopReasonWithMachException got EXC_BREAKPOINT [1,0] "
|
|
"indicating trace event, but thread is not tracing, it has "
|
|
"ResumeState %d",
|
|
thread.GetTemporaryResumeState());
|
|
if (RegisterContextSP regctx = thread.GetRegisterContext()) {
|
|
if (const RegisterInfo *ri = regctx->GetRegisterInfoByName("esr")) {
|
|
uint32_t esr =
|
|
(uint32_t)regctx->ReadRegisterAsUnsigned(ri, UINT32_MAX);
|
|
if (esr != UINT32_MAX) {
|
|
s.Printf(" esr value: 0x%" PRIx32, esr);
|
|
}
|
|
}
|
|
}
|
|
thread.GetProcess()->DumpPluginHistory(s);
|
|
llvm::report_fatal_error(s.GetData());
|
|
lldbassert(
|
|
false &&
|
|
"CreateStopReasonWithMachException got EXC_BREAKPOINT [1,0] "
|
|
"indicating trace event, but thread was not doing a step.");
|
|
}
|
|
#endif
|
|
}
|
|
if (exc_code == 0x102) // EXC_ARM_DA_DEBUG
|
|
{
|
|
// LWP_TODO: We need to find the WatchpointResource that matches
|
|
// the address, and evaluate its Watchpoints.
|
|
|
|
// It's a watchpoint, then, if the exc_sub_code indicates a
|
|
// known/enabled data break address from our watchpoint list.
|
|
lldb::WatchpointSP wp_sp;
|
|
if (target)
|
|
wp_sp = target->GetWatchpointList().FindByAddress(
|
|
(lldb::addr_t)exc_sub_code);
|
|
if (wp_sp && wp_sp->IsEnabled()) {
|
|
return StopInfo::CreateStopReasonWithWatchpointID(thread,
|
|
wp_sp->GetID());
|
|
}
|
|
// EXC_ARM_DA_DEBUG seems to be reused for EXC_BREAKPOINT as well as
|
|
// EXC_BAD_ACCESS
|
|
if (thread.GetTemporaryResumeState() == eStateStepping)
|
|
return StopInfo::CreateStopReasonToTrace(thread);
|
|
}
|
|
// It looks like exc_sub_code has the 4 bytes of the instruction that
|
|
// triggered the exception, i.e. our breakpoint opcode
|
|
is_actual_breakpoint = exc_code == 1;
|
|
break;
|
|
}
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
if (is_actual_breakpoint) {
|
|
RegisterContextSP reg_ctx_sp(thread.GetRegisterContext());
|
|
addr_t pc = reg_ctx_sp->GetPC() - pc_decrement;
|
|
|
|
ProcessSP process_sp(thread.CalculateProcess());
|
|
|
|
lldb::BreakpointSiteSP bp_site_sp;
|
|
if (process_sp)
|
|
bp_site_sp = process_sp->GetBreakpointSiteList().FindByAddress(pc);
|
|
if (bp_site_sp && bp_site_sp->IsEnabled()) {
|
|
// Update the PC if we were asked to do so, but only do so if we find
|
|
// a breakpoint that we know about cause this could be a trap
|
|
// instruction in the code
|
|
if (pc_decrement > 0 && adjust_pc_if_needed)
|
|
reg_ctx_sp->SetPC(pc);
|
|
|
|
// If the breakpoint is for this thread, then we'll report the hit,
|
|
// but if it is for another thread, we can just report no reason. We
|
|
// don't need to worry about stepping over the breakpoint here, that
|
|
// will be taken care of when the thread resumes and notices that
|
|
// there's a breakpoint under the pc. If we have an operating system
|
|
// plug-in, we might have set a thread specific breakpoint using the
|
|
// operating system thread ID, so we can't make any assumptions about
|
|
// the thread ID so we must always report the breakpoint regardless
|
|
// of the thread.
|
|
if (bp_site_sp->ValidForThisThread(thread) ||
|
|
thread.GetProcess()->GetOperatingSystem() != nullptr)
|
|
return StopInfo::CreateStopReasonWithBreakpointSiteID(
|
|
thread, bp_site_sp->GetID());
|
|
else if (is_trace_if_actual_breakpoint_missing)
|
|
return StopInfo::CreateStopReasonToTrace(thread);
|
|
else
|
|
return StopInfoSP();
|
|
}
|
|
|
|
// Don't call this a trace if we weren't single stepping this thread.
|
|
if (is_trace_if_actual_breakpoint_missing &&
|
|
thread.GetTemporaryResumeState() == eStateStepping) {
|
|
return StopInfo::CreateStopReasonToTrace(thread);
|
|
}
|
|
}
|
|
} break;
|
|
|
|
case 7: // EXC_SYSCALL
|
|
case 8: // EXC_MACH_SYSCALL
|
|
case 9: // EXC_RPC_ALERT
|
|
case 10: // EXC_CRASH
|
|
break;
|
|
}
|
|
|
|
return StopInfoSP(new StopInfoMachException(thread, exc_type, exc_data_count,
|
|
exc_code, exc_sub_code));
|
|
}
|