diff options
Diffstat (limited to 'lldb/source/Plugins/Process/FreeBSD/NativeProcessFreeBSD.cpp')
| -rw-r--r-- | lldb/source/Plugins/Process/FreeBSD/NativeProcessFreeBSD.cpp | 1011 |
1 files changed, 1011 insertions, 0 deletions
diff --git a/lldb/source/Plugins/Process/FreeBSD/NativeProcessFreeBSD.cpp b/lldb/source/Plugins/Process/FreeBSD/NativeProcessFreeBSD.cpp new file mode 100644 index 000000000000..d6426b3d2367 --- /dev/null +++ b/lldb/source/Plugins/Process/FreeBSD/NativeProcessFreeBSD.cpp @@ -0,0 +1,1011 @@ +//===-- NativeProcessFreeBSD.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 "NativeProcessFreeBSD.h" + +// clang-format off +#include <sys/types.h> +#include <sys/ptrace.h> +#include <sys/sysctl.h> +#include <sys/user.h> +#include <sys/wait.h> +#include <machine/elf.h> +// clang-format on + +#include "Plugins/Process/POSIX/ProcessPOSIXLog.h" +#include "lldb/Host/HostProcess.h" +#include "lldb/Host/posix/ProcessLauncherPosixFork.h" +#include "lldb/Target/Process.h" +#include "lldb/Utility/State.h" +#include "llvm/Support/Errno.h" + +using namespace lldb; +using namespace lldb_private; +using namespace lldb_private::process_freebsd; +using namespace llvm; + +// Simple helper function to ensure flags are enabled on the given file +// descriptor. +static Status EnsureFDFlags(int fd, int flags) { + Status error; + + int status = fcntl(fd, F_GETFL); + if (status == -1) { + error.SetErrorToErrno(); + return error; + } + + if (fcntl(fd, F_SETFL, status | flags) == -1) { + error.SetErrorToErrno(); + return error; + } + + return error; +} + +// Public Static Methods + +llvm::Expected<std::unique_ptr<NativeProcessProtocol>> +NativeProcessFreeBSD::Factory::Launch(ProcessLaunchInfo &launch_info, + NativeDelegate &native_delegate, + MainLoop &mainloop) const { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + + Status status; + ::pid_t pid = ProcessLauncherPosixFork() + .LaunchProcess(launch_info, status) + .GetProcessId(); + LLDB_LOG(log, "pid = {0:x}", pid); + if (status.Fail()) { + LLDB_LOG(log, "failed to launch process: {0}", status); + return status.ToError(); + } + + // Wait for the child process to trap on its call to execve. + int wstatus; + ::pid_t wpid = llvm::sys::RetryAfterSignal(-1, ::waitpid, pid, &wstatus, 0); + assert(wpid == pid); + (void)wpid; + if (!WIFSTOPPED(wstatus)) { + LLDB_LOG(log, "Could not sync with inferior process: wstatus={1}", + WaitStatus::Decode(wstatus)); + return llvm::make_error<StringError>("Could not sync with inferior process", + llvm::inconvertibleErrorCode()); + } + LLDB_LOG(log, "inferior started, now in stopped state"); + + ProcessInstanceInfo Info; + if (!Host::GetProcessInfo(pid, Info)) { + return llvm::make_error<StringError>("Cannot get process architecture", + llvm::inconvertibleErrorCode()); + } + + // Set the architecture to the exe architecture. + LLDB_LOG(log, "pid = {0:x}, detected architecture {1}", pid, + Info.GetArchitecture().GetArchitectureName()); + + std::unique_ptr<NativeProcessFreeBSD> process_up(new NativeProcessFreeBSD( + pid, launch_info.GetPTY().ReleasePrimaryFileDescriptor(), native_delegate, + Info.GetArchitecture(), mainloop)); + + status = process_up->SetupTrace(); + if (status.Fail()) + return status.ToError(); + + for (const auto &thread : process_up->m_threads) + static_cast<NativeThreadFreeBSD &>(*thread).SetStoppedBySignal(SIGSTOP); + process_up->SetState(StateType::eStateStopped, false); + + return std::move(process_up); +} + +llvm::Expected<std::unique_ptr<NativeProcessProtocol>> +NativeProcessFreeBSD::Factory::Attach( + lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate, + MainLoop &mainloop) const { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + LLDB_LOG(log, "pid = {0:x}", pid); + + // Retrieve the architecture for the running process. + ProcessInstanceInfo Info; + if (!Host::GetProcessInfo(pid, Info)) { + return llvm::make_error<StringError>("Cannot get process architecture", + llvm::inconvertibleErrorCode()); + } + + std::unique_ptr<NativeProcessFreeBSD> process_up(new NativeProcessFreeBSD( + pid, -1, native_delegate, Info.GetArchitecture(), mainloop)); + + Status status = process_up->Attach(); + if (!status.Success()) + return status.ToError(); + + return std::move(process_up); +} + +NativeProcessFreeBSD::Extension +NativeProcessFreeBSD::Factory::GetSupportedExtensions() const { + return Extension::multiprocess | Extension::fork | Extension::vfork | + Extension::pass_signals | Extension::auxv | Extension::libraries_svr4; +} + +// Public Instance Methods + +NativeProcessFreeBSD::NativeProcessFreeBSD(::pid_t pid, int terminal_fd, + NativeDelegate &delegate, + const ArchSpec &arch, + MainLoop &mainloop) + : NativeProcessELF(pid, terminal_fd, delegate), m_arch(arch), + m_main_loop(mainloop) { + if (m_terminal_fd != -1) { + Status status = EnsureFDFlags(m_terminal_fd, O_NONBLOCK); + assert(status.Success()); + } + + Status status; + m_sigchld_handle = mainloop.RegisterSignal( + SIGCHLD, [this](MainLoopBase &) { SigchldHandler(); }, status); + assert(m_sigchld_handle && status.Success()); +} + +// Handles all waitpid events from the inferior process. +void NativeProcessFreeBSD::MonitorCallback(lldb::pid_t pid, int signal) { + switch (signal) { + case SIGTRAP: + return MonitorSIGTRAP(pid); + case SIGSTOP: + return MonitorSIGSTOP(pid); + default: + return MonitorSignal(pid, signal); + } +} + +void NativeProcessFreeBSD::MonitorExited(lldb::pid_t pid, WaitStatus status) { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + + LLDB_LOG(log, "got exit signal({0}) , pid = {1}", status, pid); + + /* Stop Tracking All Threads attached to Process */ + m_threads.clear(); + + SetExitStatus(status, true); + + // Notify delegate that our process has exited. + SetState(StateType::eStateExited, true); +} + +void NativeProcessFreeBSD::MonitorSIGSTOP(lldb::pid_t pid) { + /* Stop all Threads attached to Process */ + for (const auto &thread : m_threads) { + static_cast<NativeThreadFreeBSD &>(*thread).SetStoppedBySignal(SIGSTOP, + nullptr); + } + SetState(StateType::eStateStopped, true); +} + +void NativeProcessFreeBSD::MonitorSIGTRAP(lldb::pid_t pid) { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + struct ptrace_lwpinfo info; + + const auto siginfo_err = PtraceWrapper(PT_LWPINFO, pid, &info, sizeof(info)); + if (siginfo_err.Fail()) { + LLDB_LOG(log, "PT_LWPINFO failed {0}", siginfo_err); + return; + } + assert(info.pl_event == PL_EVENT_SIGNAL); + + LLDB_LOG(log, "got SIGTRAP, pid = {0}, lwpid = {1}, flags = {2:x}", pid, + info.pl_lwpid, info.pl_flags); + NativeThreadFreeBSD *thread = nullptr; + + if (info.pl_flags & (PL_FLAG_BORN | PL_FLAG_EXITED)) { + if (info.pl_flags & PL_FLAG_BORN) { + LLDB_LOG(log, "monitoring new thread, tid = {0}", info.pl_lwpid); + NativeThreadFreeBSD &t = AddThread(info.pl_lwpid); + + // Technically, the FreeBSD kernel copies the debug registers to new + // threads. However, there is a non-negligible delay between acquiring + // the DR values and reporting the new thread during which the user may + // establish a new watchpoint. In order to ensure that watchpoints + // established during this period are propagated to new threads, + // explicitly copy the DR value at the time the new thread is reported. + // + // See also: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=250954 + + llvm::Error error = t.CopyWatchpointsFrom( + static_cast<NativeThreadFreeBSD &>(*GetCurrentThread())); + if (error) { + LLDB_LOG_ERROR(log, std::move(error), + "failed to copy watchpoints to new thread {1}: {0}", + info.pl_lwpid); + SetState(StateType::eStateInvalid); + return; + } + } else /*if (info.pl_flags & PL_FLAG_EXITED)*/ { + LLDB_LOG(log, "thread exited, tid = {0}", info.pl_lwpid); + RemoveThread(info.pl_lwpid); + } + + Status error = + PtraceWrapper(PT_CONTINUE, pid, reinterpret_cast<void *>(1), 0); + if (error.Fail()) + SetState(StateType::eStateInvalid); + return; + } + + if (info.pl_flags & PL_FLAG_EXEC) { + Status error = ReinitializeThreads(); + if (error.Fail()) { + SetState(StateType::eStateInvalid); + return; + } + + // Let our delegate know we have just exec'd. + NotifyDidExec(); + + for (const auto &thread : m_threads) + static_cast<NativeThreadFreeBSD &>(*thread).SetStoppedByExec(); + SetState(StateType::eStateStopped, true); + return; + } + + if (info.pl_lwpid > 0) { + for (const auto &t : m_threads) { + if (t->GetID() == static_cast<lldb::tid_t>(info.pl_lwpid)) + thread = static_cast<NativeThreadFreeBSD *>(t.get()); + static_cast<NativeThreadFreeBSD *>(t.get())->SetStoppedWithNoReason(); + } + if (!thread) + LLDB_LOG(log, "thread not found in m_threads, pid = {0}, LWP = {1}", pid, + info.pl_lwpid); + } + + if (info.pl_flags & PL_FLAG_FORKED) { + assert(thread); + MonitorClone(info.pl_child_pid, info.pl_flags & PL_FLAG_VFORKED, *thread); + return; + } + + if (info.pl_flags & PL_FLAG_VFORK_DONE) { + assert(thread); + if ((m_enabled_extensions & Extension::vfork) == Extension::vfork) { + thread->SetStoppedByVForkDone(); + SetState(StateType::eStateStopped, true); + } else { + Status error = + PtraceWrapper(PT_CONTINUE, pid, reinterpret_cast<void *>(1), 0); + if (error.Fail()) + SetState(StateType::eStateInvalid); + } + return; + } + + if (info.pl_flags & PL_FLAG_SI) { + assert(info.pl_siginfo.si_signo == SIGTRAP); + LLDB_LOG(log, "SIGTRAP siginfo: si_code = {0}, pid = {1}", + info.pl_siginfo.si_code, info.pl_siginfo.si_pid); + + switch (info.pl_siginfo.si_code) { + case TRAP_BRKPT: + LLDB_LOG(log, "SIGTRAP/TRAP_BRKPT: si_addr: {0}", + info.pl_siginfo.si_addr); + + if (thread) { + auto thread_info = + m_threads_stepping_with_breakpoint.find(thread->GetID()); + if (thread_info != m_threads_stepping_with_breakpoint.end()) { + thread->SetStoppedByTrace(); + Status brkpt_error = RemoveBreakpoint(thread_info->second); + if (brkpt_error.Fail()) + LLDB_LOG(log, "pid = {0} remove stepping breakpoint: {1}", + thread_info->first, brkpt_error); + m_threads_stepping_with_breakpoint.erase(thread_info); + } else + thread->SetStoppedByBreakpoint(); + FixupBreakpointPCAsNeeded(*thread); + } + SetState(StateType::eStateStopped, true); + return; + case TRAP_TRACE: + LLDB_LOG(log, "SIGTRAP/TRAP_TRACE: si_addr: {0}", + info.pl_siginfo.si_addr); + + if (thread) { + auto ®ctx = static_cast<NativeRegisterContextFreeBSD &>( + thread->GetRegisterContext()); + uint32_t wp_index = LLDB_INVALID_INDEX32; + Status error = regctx.GetWatchpointHitIndex( + wp_index, reinterpret_cast<uintptr_t>(info.pl_siginfo.si_addr)); + if (error.Fail()) + LLDB_LOG(log, + "received error while checking for watchpoint hits, pid = " + "{0}, LWP = {1}, error = {2}", + pid, info.pl_lwpid, error); + if (wp_index != LLDB_INVALID_INDEX32) { + regctx.ClearWatchpointHit(wp_index); + thread->SetStoppedByWatchpoint(wp_index); + SetState(StateType::eStateStopped, true); + break; + } + + thread->SetStoppedByTrace(); + } + + SetState(StateType::eStateStopped, true); + return; + } + } + + // Either user-generated SIGTRAP or an unknown event that would + // otherwise leave the debugger hanging. + LLDB_LOG(log, "unknown SIGTRAP, passing to generic handler"); + MonitorSignal(pid, SIGTRAP); +} + +void NativeProcessFreeBSD::MonitorSignal(lldb::pid_t pid, int signal) { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + struct ptrace_lwpinfo info; + + const auto siginfo_err = PtraceWrapper(PT_LWPINFO, pid, &info, sizeof(info)); + if (siginfo_err.Fail()) { + LLDB_LOG(log, "PT_LWPINFO failed {0}", siginfo_err); + return; + } + assert(info.pl_event == PL_EVENT_SIGNAL); + // TODO: do we need to handle !PL_FLAG_SI? + assert(info.pl_flags & PL_FLAG_SI); + assert(info.pl_siginfo.si_signo == signal); + + for (const auto &abs_thread : m_threads) { + NativeThreadFreeBSD &thread = + static_cast<NativeThreadFreeBSD &>(*abs_thread); + assert(info.pl_lwpid >= 0); + if (info.pl_lwpid == 0 || + static_cast<lldb::tid_t>(info.pl_lwpid) == thread.GetID()) + thread.SetStoppedBySignal(info.pl_siginfo.si_signo, &info.pl_siginfo); + else + thread.SetStoppedWithNoReason(); + } + SetState(StateType::eStateStopped, true); +} + +Status NativeProcessFreeBSD::PtraceWrapper(int req, lldb::pid_t pid, void *addr, + int data, int *result) { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PTRACE)); + Status error; + int ret; + + errno = 0; + ret = + ptrace(req, static_cast<::pid_t>(pid), static_cast<caddr_t>(addr), data); + + if (ret == -1) + error.SetErrorToErrno(); + + if (result) + *result = ret; + + LLDB_LOG(log, "ptrace({0}, {1}, {2}, {3})={4:x}", req, pid, addr, data, ret); + + if (error.Fail()) + LLDB_LOG(log, "ptrace() failed: {0}", error); + + return error; +} + +llvm::Expected<llvm::ArrayRef<uint8_t>> +NativeProcessFreeBSD::GetSoftwareBreakpointTrapOpcode(size_t size_hint) { + static const uint8_t g_arm_opcode[] = {0xfe, 0xde, 0xff, 0xe7}; + static const uint8_t g_thumb_opcode[] = {0x01, 0xde}; + + switch (GetArchitecture().GetMachine()) { + case llvm::Triple::arm: + switch (size_hint) { + case 2: + return llvm::makeArrayRef(g_thumb_opcode); + case 4: + return llvm::makeArrayRef(g_arm_opcode); + default: + return llvm::createStringError(llvm::inconvertibleErrorCode(), + "Unrecognised trap opcode size hint!"); + } + default: + return NativeProcessProtocol::GetSoftwareBreakpointTrapOpcode(size_hint); + } +} + +Status NativeProcessFreeBSD::Resume(const ResumeActionList &resume_actions) { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + LLDB_LOG(log, "pid {0}", GetID()); + + Status ret; + + int signal = 0; + for (const auto &abs_thread : m_threads) { + assert(abs_thread && "thread list should not contain NULL threads"); + NativeThreadFreeBSD &thread = + static_cast<NativeThreadFreeBSD &>(*abs_thread); + + const ResumeAction *action = + resume_actions.GetActionForThread(thread.GetID(), true); + // we need to explicit issue suspend requests, so it is simpler to map it + // into proper action + ResumeAction suspend_action{thread.GetID(), eStateSuspended, + LLDB_INVALID_SIGNAL_NUMBER}; + + if (action == nullptr) { + LLDB_LOG(log, "no action specified for pid {0} tid {1}", GetID(), + thread.GetID()); + action = &suspend_action; + } + + LLDB_LOG( + log, + "processing resume action state {0} signal {1} for pid {2} tid {3}", + action->state, action->signal, GetID(), thread.GetID()); + + switch (action->state) { + case eStateRunning: + ret = thread.Resume(); + break; + case eStateStepping: + ret = thread.SingleStep(); + break; + case eStateSuspended: + case eStateStopped: + if (action->signal != LLDB_INVALID_SIGNAL_NUMBER) + return Status("Passing signal to suspended thread unsupported"); + + ret = thread.Suspend(); + break; + + default: + return Status( + "NativeProcessFreeBSD::%s (): unexpected state %s specified " + "for pid %" PRIu64 ", tid %" PRIu64, + __FUNCTION__, StateAsCString(action->state), GetID(), thread.GetID()); + } + + if (!ret.Success()) + return ret; + if (action->signal != LLDB_INVALID_SIGNAL_NUMBER) + signal = action->signal; + } + + ret = + PtraceWrapper(PT_CONTINUE, GetID(), reinterpret_cast<void *>(1), signal); + if (ret.Success()) + SetState(eStateRunning, true); + return ret; +} + +Status NativeProcessFreeBSD::Halt() { + Status error; + + if (kill(GetID(), SIGSTOP) != 0) + error.SetErrorToErrno(); + return error; +} + +Status NativeProcessFreeBSD::Detach() { + Status error; + + // Stop monitoring the inferior. + m_sigchld_handle.reset(); + + // Tell ptrace to detach from the process. + if (GetID() == LLDB_INVALID_PROCESS_ID) + return error; + + return PtraceWrapper(PT_DETACH, GetID()); +} + +Status NativeProcessFreeBSD::Signal(int signo) { + Status error; + + if (kill(GetID(), signo)) + error.SetErrorToErrno(); + + return error; +} + +Status NativeProcessFreeBSD::Interrupt() { return Halt(); } + +Status NativeProcessFreeBSD::Kill() { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + LLDB_LOG(log, "pid {0}", GetID()); + + Status error; + + switch (m_state) { + case StateType::eStateInvalid: + case StateType::eStateExited: + case StateType::eStateCrashed: + case StateType::eStateDetached: + case StateType::eStateUnloaded: + // Nothing to do - the process is already dead. + LLDB_LOG(log, "ignored for PID {0} due to current state: {1}", GetID(), + StateAsCString(m_state)); + return error; + + case StateType::eStateConnected: + case StateType::eStateAttaching: + case StateType::eStateLaunching: + case StateType::eStateStopped: + case StateType::eStateRunning: + case StateType::eStateStepping: + case StateType::eStateSuspended: + // We can try to kill a process in these states. + break; + } + + return PtraceWrapper(PT_KILL, m_pid); +} + +Status NativeProcessFreeBSD::GetMemoryRegionInfo(lldb::addr_t load_addr, + MemoryRegionInfo &range_info) { + + if (m_supports_mem_region == LazyBool::eLazyBoolNo) { + // We're done. + return Status("unsupported"); + } + + Status error = PopulateMemoryRegionCache(); + if (error.Fail()) { + return error; + } + + lldb::addr_t prev_base_address = 0; + // FIXME start by finding the last region that is <= target address using + // binary search. Data is sorted. + // There can be a ton of regions on pthreads apps with lots of threads. + for (auto it = m_mem_region_cache.begin(); it != m_mem_region_cache.end(); + ++it) { + MemoryRegionInfo &proc_entry_info = it->first; + // Sanity check assumption that memory map entries are ascending. + assert((proc_entry_info.GetRange().GetRangeBase() >= prev_base_address) && + "descending memory map entries detected, unexpected"); + prev_base_address = proc_entry_info.GetRange().GetRangeBase(); + UNUSED_IF_ASSERT_DISABLED(prev_base_address); + // If the target address comes before this entry, indicate distance to next + // region. + if (load_addr < proc_entry_info.GetRange().GetRangeBase()) { + range_info.GetRange().SetRangeBase(load_addr); + range_info.GetRange().SetByteSize( + proc_entry_info.GetRange().GetRangeBase() - load_addr); + range_info.SetReadable(MemoryRegionInfo::OptionalBool::eNo); + range_info.SetWritable(MemoryRegionInfo::OptionalBool::eNo); + range_info.SetExecutable(MemoryRegionInfo::OptionalBool::eNo); + range_info.SetMapped(MemoryRegionInfo::OptionalBool::eNo); + return error; + } else if (proc_entry_info.GetRange().Contains(load_addr)) { + // The target address is within the memory region we're processing here. + range_info = proc_entry_info; + return error; + } + // The target memory address comes somewhere after the region we just + // parsed. + } + // If we made it here, we didn't find an entry that contained the given + // address. Return the load_addr as start and the amount of bytes betwwen + // load address and the end of the memory as size. + range_info.GetRange().SetRangeBase(load_addr); + range_info.GetRange().SetRangeEnd(LLDB_INVALID_ADDRESS); + range_info.SetReadable(MemoryRegionInfo::OptionalBool::eNo); + range_info.SetWritable(MemoryRegionInfo::OptionalBool::eNo); + range_info.SetExecutable(MemoryRegionInfo::OptionalBool::eNo); + range_info.SetMapped(MemoryRegionInfo::OptionalBool::eNo); + return error; +} + +Status NativeProcessFreeBSD::PopulateMemoryRegionCache() { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + // If our cache is empty, pull the latest. There should always be at least + // one memory region if memory region handling is supported. + if (!m_mem_region_cache.empty()) { + LLDB_LOG(log, "reusing {0} cached memory region entries", + m_mem_region_cache.size()); + return Status(); + } + + int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_VMMAP, static_cast<int>(m_pid)}; + int ret; + size_t len; + + ret = ::sysctl(mib, 4, nullptr, &len, nullptr, 0); + if (ret != 0) { + m_supports_mem_region = LazyBool::eLazyBoolNo; + return Status("sysctl() for KERN_PROC_VMMAP failed"); + } + + std::unique_ptr<WritableMemoryBuffer> buf = + llvm::WritableMemoryBuffer::getNewMemBuffer(len); + ret = ::sysctl(mib, 4, buf->getBufferStart(), &len, nullptr, 0); + if (ret != 0) { + m_supports_mem_region = LazyBool::eLazyBoolNo; + return Status("sysctl() for KERN_PROC_VMMAP failed"); + } + + char *bp = buf->getBufferStart(); + char *end = bp + len; + while (bp < end) { + auto *kv = reinterpret_cast<struct kinfo_vmentry *>(bp); + if (kv->kve_structsize == 0) + break; + bp += kv->kve_structsize; + + MemoryRegionInfo info; + info.Clear(); + info.GetRange().SetRangeBase(kv->kve_start); + info.GetRange().SetRangeEnd(kv->kve_end); + info.SetMapped(MemoryRegionInfo::OptionalBool::eYes); + + if (kv->kve_protection & VM_PROT_READ) + info.SetReadable(MemoryRegionInfo::OptionalBool::eYes); + else + info.SetReadable(MemoryRegionInfo::OptionalBool::eNo); + + if (kv->kve_protection & VM_PROT_WRITE) + info.SetWritable(MemoryRegionInfo::OptionalBool::eYes); + else + info.SetWritable(MemoryRegionInfo::OptionalBool::eNo); + + if (kv->kve_protection & VM_PROT_EXECUTE) + info.SetExecutable(MemoryRegionInfo::OptionalBool::eYes); + else + info.SetExecutable(MemoryRegionInfo::OptionalBool::eNo); + + if (kv->kve_path[0]) + info.SetName(kv->kve_path); + + m_mem_region_cache.emplace_back(info, + FileSpec(info.GetName().GetCString())); + } + + if (m_mem_region_cache.empty()) { + // No entries after attempting to read them. This shouldn't happen. Assume + // we don't support map entries. + LLDB_LOG(log, "failed to find any vmmap entries, assuming no support " + "for memory region metadata retrieval"); + m_supports_mem_region = LazyBool::eLazyBoolNo; + return Status("not supported"); + } + LLDB_LOG(log, "read {0} memory region entries from process {1}", + m_mem_region_cache.size(), GetID()); + // We support memory retrieval, remember that. + m_supports_mem_region = LazyBool::eLazyBoolYes; + + return Status(); +} + +size_t NativeProcessFreeBSD::UpdateThreads() { return m_threads.size(); } + +Status NativeProcessFreeBSD::SetBreakpoint(lldb::addr_t addr, uint32_t size, + bool hardware) { + if (hardware) + return SetHardwareBreakpoint(addr, size); + return SetSoftwareBreakpoint(addr, size); +} + +Status NativeProcessFreeBSD::GetLoadedModuleFileSpec(const char *module_path, + FileSpec &file_spec) { + Status error = PopulateMemoryRegionCache(); + if (error.Fail()) + return error; + + FileSpec module_file_spec(module_path); + FileSystem::Instance().Resolve(module_file_spec); + + file_spec.Clear(); + for (const auto &it : m_mem_region_cache) { + if (it.second.GetFilename() == module_file_spec.GetFilename()) { + file_spec = it.second; + return Status(); + } + } + return Status("Module file (%s) not found in process' memory map!", + module_file_spec.GetFilename().AsCString()); +} + +Status +NativeProcessFreeBSD::GetFileLoadAddress(const llvm::StringRef &file_name, + lldb::addr_t &load_addr) { + load_addr = LLDB_INVALID_ADDRESS; + Status error = PopulateMemoryRegionCache(); + if (error.Fail()) + return error; + + FileSpec file(file_name); + for (const auto &it : m_mem_region_cache) { + if (it.second == file) { + load_addr = it.first.GetRange().GetRangeBase(); + return Status(); + } + } + return Status("No load address found for file %s.", file_name.str().c_str()); +} + +void NativeProcessFreeBSD::SigchldHandler() { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + int status; + ::pid_t wait_pid = + llvm::sys::RetryAfterSignal(-1, waitpid, GetID(), &status, WNOHANG); + + if (wait_pid == 0) + return; + + if (wait_pid == -1) { + Status error(errno, eErrorTypePOSIX); + LLDB_LOG(log, "waitpid ({0}, &status, _) failed: {1}", GetID(), error); + return; + } + + WaitStatus wait_status = WaitStatus::Decode(status); + bool exited = wait_status.type == WaitStatus::Exit || + (wait_status.type == WaitStatus::Signal && + wait_pid == static_cast<::pid_t>(GetID())); + + LLDB_LOG(log, + "waitpid ({0}, &status, _) => pid = {1}, status = {2}, exited = {3}", + GetID(), wait_pid, status, exited); + + if (exited) + MonitorExited(wait_pid, wait_status); + else { + assert(wait_status.type == WaitStatus::Stop); + MonitorCallback(wait_pid, wait_status.status); + } +} + +bool NativeProcessFreeBSD::HasThreadNoLock(lldb::tid_t thread_id) { + for (const auto &thread : m_threads) { + assert(thread && "thread list should not contain NULL threads"); + if (thread->GetID() == thread_id) { + // We have this thread. + return true; + } + } + + // We don't have this thread. + return false; +} + +NativeThreadFreeBSD &NativeProcessFreeBSD::AddThread(lldb::tid_t thread_id) { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_THREAD)); + LLDB_LOG(log, "pid {0} adding thread with tid {1}", GetID(), thread_id); + + assert(thread_id > 0); + assert(!HasThreadNoLock(thread_id) && + "attempted to add a thread by id that already exists"); + + // If this is the first thread, save it as the current thread + if (m_threads.empty()) + SetCurrentThreadID(thread_id); + + m_threads.push_back(std::make_unique<NativeThreadFreeBSD>(*this, thread_id)); + return static_cast<NativeThreadFreeBSD &>(*m_threads.back()); +} + +void NativeProcessFreeBSD::RemoveThread(lldb::tid_t thread_id) { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_THREAD)); + LLDB_LOG(log, "pid {0} removing thread with tid {1}", GetID(), thread_id); + + assert(thread_id > 0); + assert(HasThreadNoLock(thread_id) && + "attempted to remove a thread that does not exist"); + + for (auto it = m_threads.begin(); it != m_threads.end(); ++it) { + if ((*it)->GetID() == thread_id) { + m_threads.erase(it); + break; + } + } +} + +Status NativeProcessFreeBSD::Attach() { + // Attach to the requested process. + // An attach will cause the thread to stop with a SIGSTOP. + Status status = PtraceWrapper(PT_ATTACH, m_pid); + if (status.Fail()) + return status; + + int wstatus; + // Need to use WALLSIG otherwise we receive an error with errno=ECHLD At this + // point we should have a thread stopped if waitpid succeeds. + if ((wstatus = llvm::sys::RetryAfterSignal(-1, waitpid, m_pid, nullptr, 0)) < + 0) + return Status(errno, eErrorTypePOSIX); + + // Initialize threads and tracing status + // NB: this needs to be called before we set thread state + status = SetupTrace(); + if (status.Fail()) + return status; + + for (const auto &thread : m_threads) + static_cast<NativeThreadFreeBSD &>(*thread).SetStoppedBySignal(SIGSTOP); + + // Let our process instance know the thread has stopped. + SetCurrentThreadID(m_threads.front()->GetID()); + SetState(StateType::eStateStopped, false); + return Status(); +} + +Status NativeProcessFreeBSD::ReadMemory(lldb::addr_t addr, void *buf, + size_t size, size_t &bytes_read) { + unsigned char *dst = static_cast<unsigned char *>(buf); + struct ptrace_io_desc io; + + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_MEMORY)); + LLDB_LOG(log, "addr = {0}, buf = {1}, size = {2}", addr, buf, size); + + bytes_read = 0; + io.piod_op = PIOD_READ_D; + io.piod_len = size; + + do { + io.piod_offs = (void *)(addr + bytes_read); + io.piod_addr = dst + bytes_read; + + Status error = NativeProcessFreeBSD::PtraceWrapper(PT_IO, GetID(), &io); + if (error.Fail() || io.piod_len == 0) + return error; + + bytes_read += io.piod_len; + io.piod_len = size - bytes_read; + } while (bytes_read < size); + + return Status(); +} + +Status NativeProcessFreeBSD::WriteMemory(lldb::addr_t addr, const void *buf, + size_t size, size_t &bytes_written) { + const unsigned char *src = static_cast<const unsigned char *>(buf); + Status error; + struct ptrace_io_desc io; + + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_MEMORY)); + LLDB_LOG(log, "addr = {0}, buf = {1}, size = {2}", addr, buf, size); + + bytes_written = 0; + io.piod_op = PIOD_WRITE_D; + io.piod_len = size; + + do { + io.piod_addr = + const_cast<void *>(static_cast<const void *>(src + bytes_written)); + io.piod_offs = (void *)(addr + bytes_written); + + Status error = NativeProcessFreeBSD::PtraceWrapper(PT_IO, GetID(), &io); + if (error.Fail() || io.piod_len == 0) + return error; + + bytes_written += io.piod_len; + io.piod_len = size - bytes_written; + } while (bytes_written < size); + + return error; +} + +llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> +NativeProcessFreeBSD::GetAuxvData() const { + int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_AUXV, static_cast<int>(GetID())}; + size_t auxv_size = AT_COUNT * sizeof(Elf_Auxinfo); + std::unique_ptr<WritableMemoryBuffer> buf = + llvm::WritableMemoryBuffer::getNewMemBuffer(auxv_size); + + if (::sysctl(mib, 4, buf->getBufferStart(), &auxv_size, nullptr, 0) != 0) + return std::error_code(errno, std::generic_category()); + + return buf; +} + +Status NativeProcessFreeBSD::SetupTrace() { + // Enable event reporting + int events; + Status status = + PtraceWrapper(PT_GET_EVENT_MASK, GetID(), &events, sizeof(events)); + if (status.Fail()) + return status; + events |= PTRACE_LWP | PTRACE_FORK | PTRACE_VFORK; + status = PtraceWrapper(PT_SET_EVENT_MASK, GetID(), &events, sizeof(events)); + if (status.Fail()) + return status; + + return ReinitializeThreads(); +} + +Status NativeProcessFreeBSD::ReinitializeThreads() { + // Clear old threads + m_threads.clear(); + + int num_lwps; + Status error = PtraceWrapper(PT_GETNUMLWPS, GetID(), nullptr, 0, &num_lwps); + if (error.Fail()) + return error; + + std::vector<lwpid_t> lwp_ids; + lwp_ids.resize(num_lwps); + error = PtraceWrapper(PT_GETLWPLIST, GetID(), lwp_ids.data(), + lwp_ids.size() * sizeof(lwpid_t), &num_lwps); + if (error.Fail()) + return error; + + // Reinitialize from scratch threads and register them in process + for (lwpid_t lwp : lwp_ids) + AddThread(lwp); + + return error; +} + +bool NativeProcessFreeBSD::SupportHardwareSingleStepping() const { + return !m_arch.IsMIPS(); +} + +void NativeProcessFreeBSD::MonitorClone(::pid_t child_pid, bool is_vfork, + NativeThreadFreeBSD &parent_thread) { + Log *log(ProcessPOSIXLog::GetLogIfAllCategoriesSet(POSIX_LOG_PROCESS)); + LLDB_LOG(log, "fork, child_pid={0}", child_pid); + + int status; + ::pid_t wait_pid = + llvm::sys::RetryAfterSignal(-1, ::waitpid, child_pid, &status, 0); + if (wait_pid != child_pid) { + LLDB_LOG(log, + "waiting for pid {0} failed. Assuming the pid has " + "disappeared in the meantime", + child_pid); + return; + } + if (WIFEXITED(status)) { + LLDB_LOG(log, + "waiting for pid {0} returned an 'exited' event. Not " + "tracking it.", + child_pid); + return; + } + + struct ptrace_lwpinfo info; + const auto siginfo_err = PtraceWrapper(PT_LWPINFO, child_pid, &info, sizeof(info)); + if (siginfo_err.Fail()) { + LLDB_LOG(log, "PT_LWPINFO failed {0}", siginfo_err); + return; + } + assert(info.pl_event == PL_EVENT_SIGNAL); + lldb::tid_t child_tid = info.pl_lwpid; + + std::unique_ptr<NativeProcessFreeBSD> child_process{ + new NativeProcessFreeBSD(static_cast<::pid_t>(child_pid), m_terminal_fd, + m_delegate, m_arch, m_main_loop)}; + if (!is_vfork) + child_process->m_software_breakpoints = m_software_breakpoints; + + Extension expected_ext = is_vfork ? Extension::vfork : Extension::fork; + if ((m_enabled_extensions & expected_ext) == expected_ext) { + child_process->SetupTrace(); + for (const auto &thread : child_process->m_threads) + static_cast<NativeThreadFreeBSD &>(*thread).SetStoppedBySignal(SIGSTOP); + child_process->SetState(StateType::eStateStopped, false); + + m_delegate.NewSubprocess(this, std::move(child_process)); + if (is_vfork) + parent_thread.SetStoppedByVFork(child_pid, child_tid); + else + parent_thread.SetStoppedByFork(child_pid, child_tid); + SetState(StateType::eStateStopped, true); + } else { + child_process->Detach(); + Status pt_error = + PtraceWrapper(PT_CONTINUE, GetID(), reinterpret_cast<void *>(1), 0); + if (pt_error.Fail()) { + LLDB_LOG_ERROR(log, pt_error.ToError(), + "unable to resume parent process {1}: {0}", GetID()); + SetState(StateType::eStateInvalid); + } + } +} |