1//===-- NativeProcessNetBSD.cpp -------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "NativeProcessNetBSD.h"
10
11#include "Plugins/Process/NetBSD/NativeRegisterContextNetBSD.h"
12#include "Plugins/Process/POSIX/ProcessPOSIXLog.h"
13#include "lldb/Host/HostProcess.h"
14#include "lldb/Host/common/NativeRegisterContext.h"
15#include "lldb/Host/posix/ProcessLauncherPosixFork.h"
16#include "lldb/Target/Process.h"
17#include "lldb/Utility/State.h"
18#include "llvm/Support/Errno.h"
19
20// System includes - They have to be included after framework includes because
21// they define some macros which collide with variable names in other modules
22// clang-format off
23#include <sys/types.h>
24#include <sys/ptrace.h>
25#include <sys/sysctl.h>
26#include <sys/wait.h>
27#include <uvm/uvm_prot.h>
28#include <elf.h>
29#include <util.h>
30// clang-format on
31
32using namespace lldb;
33using namespace lldb_private;
34using namespace lldb_private::process_netbsd;
35using namespace llvm;
36
37// Simple helper function to ensure flags are enabled on the given file
38// descriptor.
39static Status EnsureFDFlags(int fd, int flags) {
40 Status error;
41
42 int status = fcntl(fd: fd, F_GETFL);
43 if (status == -1) {
44 error = Status::FromErrno();
45 return error;
46 }
47
48 if (fcntl(fd: fd, F_SETFL, status | flags) == -1) {
49 error = Status::FromErrno();
50 return error;
51 }
52
53 return error;
54}
55
56// Public Static Methods
57
58llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
59NativeProcessNetBSD::Manager::Launch(ProcessLaunchInfo &launch_info,
60 NativeDelegate &native_delegate) {
61 Log *log = GetLog(mask: POSIXLog::Process);
62
63 Status status;
64 ::pid_t pid = ProcessLauncherPosixFork()
65 .LaunchProcess(launch_info, error&: status)
66 .GetProcessId();
67 LLDB_LOG(log, "pid = {0:x}", pid);
68 if (status.Fail()) {
69 LLDB_LOG(log, "failed to launch process: {0}", status);
70 return status.ToError();
71 }
72
73 // Wait for the child process to trap on its call to execve.
74 int wstatus;
75 ::pid_t wpid = llvm::sys::RetryAfterSignal(Fail: -1, F&: ::waitpid, As: pid, As: &wstatus, As: 0);
76 assert(wpid == pid);
77 (void)wpid;
78 if (!WIFSTOPPED(wstatus)) {
79 LLDB_LOG(log, "Could not sync with inferior process: wstatus={1}",
80 WaitStatus::Decode(wstatus));
81 return llvm::make_error<StringError>(Args: "Could not sync with inferior process",
82 Args: llvm::inconvertibleErrorCode());
83 }
84 LLDB_LOG(log, "inferior started, now in stopped state");
85
86 ProcessInstanceInfo Info;
87 if (!Host::GetProcessInfo(pid, proc_info&: Info)) {
88 return llvm::make_error<StringError>(Args: "Cannot get process architecture",
89 Args: llvm::inconvertibleErrorCode());
90 }
91
92 // Set the architecture to the exe architecture.
93 LLDB_LOG(log, "pid = {0:x}, detected architecture {1}", pid,
94 Info.GetArchitecture().GetArchitectureName());
95
96 std::unique_ptr<NativeProcessNetBSD> process_up(new NativeProcessNetBSD(
97 pid, launch_info.GetPTY().ReleasePrimaryFileDescriptor(), native_delegate,
98 Info.GetArchitecture(), m_mainloop));
99
100 status = process_up->SetupTrace();
101 if (status.Fail())
102 return status.ToError();
103
104 for (const auto &thread : process_up->m_threads)
105 static_cast<NativeThreadNetBSD &>(*thread).SetStoppedBySignal(SIGSTOP);
106 process_up->SetState(state: StateType::eStateStopped, notify_delegates: false);
107
108 return std::move(process_up);
109}
110
111llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
112NativeProcessNetBSD::Manager::Attach(
113 lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate) {
114 Log *log = GetLog(mask: POSIXLog::Process);
115 LLDB_LOG(log, "pid = {0:x}", pid);
116
117 // Retrieve the architecture for the running process.
118 ProcessInstanceInfo Info;
119 if (!Host::GetProcessInfo(pid, proc_info&: Info)) {
120 return llvm::make_error<StringError>(Args: "Cannot get process architecture",
121 Args: llvm::inconvertibleErrorCode());
122 }
123
124 std::unique_ptr<NativeProcessNetBSD> process_up(new NativeProcessNetBSD(
125 pid, -1, native_delegate, Info.GetArchitecture(), m_mainloop));
126
127 Status status = process_up->Attach();
128 if (!status.Success())
129 return status.ToError();
130
131 return std::move(process_up);
132}
133
134NativeProcessNetBSD::Extension
135NativeProcessNetBSD::Manager::GetSupportedExtensions() const {
136 return Extension::multiprocess | Extension::fork | Extension::vfork |
137 Extension::pass_signals | Extension::auxv | Extension::libraries_svr4 |
138 Extension::savecore;
139}
140
141// Public Instance Methods
142
143NativeProcessNetBSD::NativeProcessNetBSD(::pid_t pid, int terminal_fd,
144 NativeDelegate &delegate,
145 const ArchSpec &arch,
146 MainLoop &mainloop)
147 : NativeProcessELF(pid, terminal_fd, delegate), m_arch(arch),
148 m_main_loop(mainloop) {
149 if (m_terminal_fd != -1) {
150 Status status = EnsureFDFlags(fd: m_terminal_fd, O_NONBLOCK);
151 assert(status.Success());
152 }
153
154 Status status;
155 m_sigchld_handle = mainloop.RegisterSignal(
156 SIGCHLD, callback: [this](MainLoopBase &) { SigchldHandler(); }, error&: status);
157 assert(m_sigchld_handle && status.Success());
158}
159
160// Handles all waitpid events from the inferior process.
161void NativeProcessNetBSD::MonitorCallback(lldb::pid_t pid, int signal) {
162 switch (signal) {
163 case SIGTRAP:
164 return MonitorSIGTRAP(pid);
165 case SIGSTOP:
166 return MonitorSIGSTOP(pid);
167 default:
168 return MonitorSignal(pid, signal);
169 }
170}
171
172void NativeProcessNetBSD::MonitorExited(lldb::pid_t pid, WaitStatus status) {
173 Log *log = GetLog(mask: POSIXLog::Process);
174
175 LLDB_LOG(log, "got exit signal({0}) , pid = {1}", status, pid);
176
177 /* Stop Tracking All Threads attached to Process */
178 m_threads.clear();
179
180 SetExitStatus(status, bNotifyStateChange: true);
181
182 // Notify delegate that our process has exited.
183 SetState(state: StateType::eStateExited, notify_delegates: true);
184}
185
186void NativeProcessNetBSD::MonitorSIGSTOP(lldb::pid_t pid) {
187 ptrace_siginfo_t info;
188
189 const auto siginfo_err =
190 PtraceWrapper(req: PT_GET_SIGINFO, pid, addr: &info, data: sizeof(info));
191
192 // Get details on the signal raised.
193 if (siginfo_err.Success()) {
194 // Handle SIGSTOP from LLGS (LLDB GDB Server)
195 if (info.psi_siginfo.si_code == SI_USER &&
196 info.psi_siginfo.si_pid == ::getpid()) {
197 /* Stop Tracking all Threads attached to Process */
198 for (const auto &thread : m_threads) {
199 static_cast<NativeThreadNetBSD &>(*thread).SetStoppedBySignal(
200 SIGSTOP, info: &info.psi_siginfo);
201 }
202 }
203 SetState(state: StateType::eStateStopped, notify_delegates: true);
204 }
205}
206
207void NativeProcessNetBSD::MonitorSIGTRAP(lldb::pid_t pid) {
208 Log *log = GetLog(mask: POSIXLog::Process);
209 ptrace_siginfo_t info;
210
211 const auto siginfo_err =
212 PtraceWrapper(req: PT_GET_SIGINFO, pid, addr: &info, data: sizeof(info));
213
214 // Get details on the signal raised.
215 if (siginfo_err.Fail()) {
216 LLDB_LOG(log, "PT_GET_SIGINFO failed {0}", siginfo_err);
217 return;
218 }
219
220 LLDB_LOG(log, "got SIGTRAP, pid = {0}, lwpid = {1}, si_code = {2}", pid,
221 info.psi_lwpid, info.psi_siginfo.si_code);
222 NativeThreadNetBSD *thread = nullptr;
223
224 if (info.psi_lwpid > 0) {
225 for (const auto &t : m_threads) {
226 if (t->GetID() == static_cast<lldb::tid_t>(info.psi_lwpid)) {
227 thread = static_cast<NativeThreadNetBSD *>(t.get());
228 break;
229 }
230 static_cast<NativeThreadNetBSD *>(t.get())->SetStoppedWithNoReason();
231 }
232 if (!thread)
233 LLDB_LOG(log, "thread not found in m_threads, pid = {0}, LWP = {1}", pid,
234 info.psi_lwpid);
235 }
236
237 switch (info.psi_siginfo.si_code) {
238 case TRAP_BRKPT:
239 if (thread) {
240 thread->SetStoppedByBreakpoint();
241 FixupBreakpointPCAsNeeded(thread&: *thread);
242 }
243 SetState(state: StateType::eStateStopped, notify_delegates: true);
244 return;
245 case TRAP_TRACE:
246 if (thread)
247 thread->SetStoppedByTrace();
248 SetState(state: StateType::eStateStopped, notify_delegates: true);
249 return;
250 case TRAP_EXEC: {
251 Status error = ReinitializeThreads();
252 if (error.Fail()) {
253 SetState(state: StateType::eStateInvalid);
254 return;
255 }
256
257 // Let our delegate know we have just exec'd.
258 NotifyDidExec();
259
260 for (const auto &thread : m_threads)
261 static_cast<NativeThreadNetBSD &>(*thread).SetStoppedByExec();
262 SetState(state: StateType::eStateStopped, notify_delegates: true);
263 return;
264 }
265 case TRAP_CHLD: {
266 ptrace_state_t pst;
267 Status error = PtraceWrapper(req: PT_GET_PROCESS_STATE, pid, addr: &pst, data: sizeof(pst));
268 if (error.Fail()) {
269 SetState(state: StateType::eStateInvalid);
270 return;
271 }
272
273 assert(thread);
274 if (pst.pe_report_event == PTRACE_VFORK_DONE) {
275 if ((m_enabled_extensions & Extension::vfork) == Extension::vfork) {
276 thread->SetStoppedByVForkDone();
277 SetState(state: StateType::eStateStopped, notify_delegates: true);
278 } else {
279 Status error =
280 PtraceWrapper(PT_CONTINUE, pid, addr: reinterpret_cast<void *>(1), data: 0);
281 if (error.Fail())
282 SetState(state: StateType::eStateInvalid);
283 }
284 } else {
285 assert(pst.pe_report_event == PTRACE_FORK ||
286 pst.pe_report_event == PTRACE_VFORK);
287 MonitorClone(child_pid: pst.pe_other_pid, is_vfork: pst.pe_report_event == PTRACE_VFORK,
288 parent_thread&: *thread);
289 }
290 return;
291 }
292 case TRAP_LWP: {
293 ptrace_state_t pst;
294 Status error = PtraceWrapper(req: PT_GET_PROCESS_STATE, pid, addr: &pst, data: sizeof(pst));
295 if (error.Fail()) {
296 SetState(state: StateType::eStateInvalid);
297 return;
298 }
299
300 switch (pst.pe_report_event) {
301 case PTRACE_LWP_CREATE: {
302 LLDB_LOG(log, "monitoring new thread, pid = {0}, LWP = {1}", pid,
303 pst.pe_lwp);
304 NativeThreadNetBSD &t = AddThread(thread_id: pst.pe_lwp);
305 error = t.CopyWatchpointsFrom(
306 source&: static_cast<NativeThreadNetBSD &>(*GetCurrentThread()));
307 if (error.Fail()) {
308 LLDB_LOG(log, "failed to copy watchpoints to new thread {0}: {1}",
309 pst.pe_lwp, error);
310 SetState(state: StateType::eStateInvalid);
311 return;
312 }
313 } break;
314 case PTRACE_LWP_EXIT:
315 LLDB_LOG(log, "removing exited thread, pid = {0}, LWP = {1}", pid,
316 pst.pe_lwp);
317 RemoveThread(thread_id: pst.pe_lwp);
318 break;
319 }
320
321 error = PtraceWrapper(PT_CONTINUE, pid, addr: reinterpret_cast<void *>(1), data: 0);
322 if (error.Fail())
323 SetState(state: StateType::eStateInvalid);
324 return;
325 }
326 case TRAP_DBREG: {
327 if (!thread)
328 break;
329
330 auto &regctx = static_cast<NativeRegisterContextNetBSD &>(
331 thread->GetRegisterContext());
332 uint32_t wp_index = LLDB_INVALID_INDEX32;
333 Status error = regctx.GetWatchpointHitIndex(
334 wp_index, trap_addr: (uintptr_t)info.psi_siginfo.si_addr);
335 if (error.Fail())
336 LLDB_LOG(log,
337 "received error while checking for watchpoint hits, pid = "
338 "{0}, LWP = {1}, error = {2}",
339 pid, info.psi_lwpid, error);
340 if (wp_index != LLDB_INVALID_INDEX32) {
341 thread->SetStoppedByWatchpoint(wp_index);
342 regctx.ClearWatchpointHit(hw_index: wp_index);
343 SetState(state: StateType::eStateStopped, notify_delegates: true);
344 return;
345 }
346
347 thread->SetStoppedByTrace();
348 SetState(state: StateType::eStateStopped, notify_delegates: true);
349 return;
350 }
351 }
352
353 // Either user-generated SIGTRAP or an unknown event that would
354 // otherwise leave the debugger hanging.
355 LLDB_LOG(log, "unknown SIGTRAP, passing to generic handler");
356 MonitorSignal(pid, SIGTRAP);
357}
358
359void NativeProcessNetBSD::MonitorSignal(lldb::pid_t pid, int signal) {
360 Log *log = GetLog(mask: POSIXLog::Process);
361 ptrace_siginfo_t info;
362
363 const auto siginfo_err =
364 PtraceWrapper(req: PT_GET_SIGINFO, pid, addr: &info, data: sizeof(info));
365 if (siginfo_err.Fail()) {
366 LLDB_LOG(log, "PT_LWPINFO failed {0}", siginfo_err);
367 return;
368 }
369
370 for (const auto &abs_thread : m_threads) {
371 NativeThreadNetBSD &thread = static_cast<NativeThreadNetBSD &>(*abs_thread);
372 assert(info.psi_lwpid >= 0);
373 if (info.psi_lwpid == 0 ||
374 static_cast<lldb::tid_t>(info.psi_lwpid) == thread.GetID())
375 thread.SetStoppedBySignal(signo: info.psi_siginfo.si_signo, info: &info.psi_siginfo);
376 else
377 thread.SetStoppedWithNoReason();
378 }
379 SetState(state: StateType::eStateStopped, notify_delegates: true);
380}
381
382Status NativeProcessNetBSD::StopProcess(lldb::pid_t pid) {
383#ifdef PT_STOP
384 return PtraceWrapper(PT_STOP, pid);
385#else
386 Log *log = GetLog(mask: POSIXLog::Ptrace);
387 Status error;
388 int ret;
389
390 errno = 0;
391 ret = kill(pid: pid, SIGSTOP);
392
393 if (ret == -1)
394 error = Status::FromErrno();
395
396 LLDB_LOG(log, "kill({0}, SIGSTOP)", pid);
397
398 if (error.Fail())
399 LLDB_LOG(log, "kill() failed: {0}", error);
400
401 return error;
402#endif
403}
404
405Status NativeProcessNetBSD::PtraceWrapper(int req, lldb::pid_t pid, void *addr,
406 int data, int *result) {
407 Log *log = GetLog(mask: POSIXLog::Ptrace);
408 Status error;
409 int ret;
410
411 errno = 0;
412 ret = ptrace(req, static_cast<::pid_t>(pid), addr, data);
413
414 if (ret == -1)
415 error = Status::FromErrno();
416
417 if (result)
418 *result = ret;
419
420 LLDB_LOG(log, "ptrace({0}, {1}, {2}, {3})={4:x}", req, pid, addr, data, ret);
421
422 if (error.Fail())
423 LLDB_LOG(log, "ptrace() failed: {0}", error);
424
425 return error;
426}
427
428static llvm::Expected<ptrace_siginfo_t> ComputeSignalInfo(
429 const std::vector<std::unique_ptr<NativeThreadProtocol>> &threads,
430 const ResumeActionList &resume_actions) {
431 // We need to account for three possible scenarios:
432 // 1. no signal being sent.
433 // 2. a signal being sent to one thread.
434 // 3. a signal being sent to the whole process.
435
436 // Count signaled threads. While at it, determine which signal is being sent
437 // and ensure there's only one.
438 size_t signaled_threads = 0;
439 int signal = LLDB_INVALID_SIGNAL_NUMBER;
440 lldb::tid_t signaled_lwp;
441 for (const auto &thread : threads) {
442 assert(thread && "thread list should not contain NULL threads");
443 const ResumeAction *action =
444 resume_actions.GetActionForThread(tid: thread->GetID(), default_ok: true);
445 if (action) {
446 if (action->signal != LLDB_INVALID_SIGNAL_NUMBER) {
447 signaled_threads++;
448 if (action->signal != signal) {
449 if (signal != LLDB_INVALID_SIGNAL_NUMBER)
450 return Status::FromErrorString(
451 str: "NetBSD does not support passing multiple signals "
452 "simultaneously")
453 .ToError();
454 signal = action->signal;
455 signaled_lwp = thread->GetID();
456 }
457 }
458 }
459 }
460
461 if (signaled_threads == 0) {
462 ptrace_siginfo_t siginfo;
463 siginfo.psi_siginfo.si_signo = LLDB_INVALID_SIGNAL_NUMBER;
464 return siginfo;
465 }
466
467 if (signaled_threads > 1 && signaled_threads < threads.size())
468 return Status::FromErrorString(
469 str: "NetBSD does not support passing signal to 1<i<all threads")
470 .ToError();
471
472 ptrace_siginfo_t siginfo;
473 siginfo.psi_siginfo.si_signo = signal;
474 siginfo.psi_siginfo.si_code = SI_USER;
475 siginfo.psi_siginfo.si_pid = getpid();
476 siginfo.psi_siginfo.si_uid = getuid();
477 if (signaled_threads == 1)
478 siginfo.psi_lwpid = signaled_lwp;
479 else // signal for the whole process
480 siginfo.psi_lwpid = 0;
481 return siginfo;
482}
483
484Status NativeProcessNetBSD::Resume(const ResumeActionList &resume_actions) {
485 Log *log = GetLog(mask: POSIXLog::Process);
486 LLDB_LOG(log, "pid {0}", GetID());
487
488 Status ret;
489
490 Expected<ptrace_siginfo_t> siginfo =
491 ComputeSignalInfo(m_threads, resume_actions);
492 if (!siginfo)
493 return Status(siginfo.takeError());
494
495 for (const auto &abs_thread : m_threads) {
496 assert(abs_thread && "thread list should not contain NULL threads");
497 NativeThreadNetBSD &thread = static_cast<NativeThreadNetBSD &>(*abs_thread);
498
499 const ResumeAction *action =
500 resume_actions.GetActionForThread(tid: thread.GetID(), default_ok: true);
501 // we need to explicit issue suspend requests, so it is simpler to map it
502 // into proper action
503 ResumeAction suspend_action{.tid: thread.GetID(), .state: eStateSuspended,
504 LLDB_INVALID_SIGNAL_NUMBER};
505
506 if (action == nullptr) {
507 LLDB_LOG(log, "no action specified for pid {0} tid {1}", GetID(),
508 thread.GetID());
509 action = &suspend_action;
510 }
511
512 LLDB_LOG(
513 log,
514 "processing resume action state {0} signal {1} for pid {2} tid {3}",
515 action->state, action->signal, GetID(), thread.GetID());
516
517 switch (action->state) {
518 case eStateRunning:
519 ret = thread.Resume();
520 break;
521 case eStateStepping:
522 ret = thread.SingleStep();
523 break;
524 case eStateSuspended:
525 case eStateStopped:
526 if (action->signal != LLDB_INVALID_SIGNAL_NUMBER)
527 return Status::FromErrorString(
528 str: "Passing signal to suspended thread unsupported");
529
530 ret = thread.Suspend();
531 break;
532
533 default:
534 return Status::FromErrorStringWithFormat(
535 format: "NativeProcessNetBSD::%s (): unexpected state %s specified "
536 "for pid %" PRIu64 ", tid %" PRIu64,
537 __FUNCTION__, StateAsCString(state: action->state), GetID(), thread.GetID());
538 }
539
540 if (!ret.Success())
541 return ret;
542 }
543
544 int signal = 0;
545 if (siginfo->psi_siginfo.si_signo != LLDB_INVALID_SIGNAL_NUMBER) {
546 ret = PtraceWrapper(req: PT_SET_SIGINFO, pid: GetID(), addr: &siginfo.get(),
547 data: sizeof(*siginfo));
548 if (!ret.Success())
549 return ret;
550 signal = siginfo->psi_siginfo.si_signo;
551 }
552
553 ret =
554 PtraceWrapper(PT_CONTINUE, pid: GetID(), addr: reinterpret_cast<void *>(1), data: signal);
555 if (ret.Success())
556 SetState(state: eStateRunning, notify_delegates: true);
557 return ret;
558}
559
560Status NativeProcessNetBSD::Halt() { return StopProcess(pid: GetID()); }
561
562Status NativeProcessNetBSD::Detach() {
563 Status error;
564
565 // Stop monitoring the inferior.
566 m_sigchld_handle.reset();
567
568 // Tell ptrace to detach from the process.
569 if (GetID() == LLDB_INVALID_PROCESS_ID)
570 return error;
571
572 return PtraceWrapper(PT_DETACH, pid: GetID(), addr: reinterpret_cast<void *>(1));
573}
574
575Status NativeProcessNetBSD::Signal(int signo) {
576 Status error;
577
578 if (kill(pid: GetID(), sig: signo))
579 error = Status::FromErrno();
580
581 return error;
582}
583
584Status NativeProcessNetBSD::Interrupt() { return StopProcess(pid: GetID()); }
585
586Status NativeProcessNetBSD::Kill() {
587 Log *log = GetLog(mask: POSIXLog::Process);
588 LLDB_LOG(log, "pid {0}", GetID());
589
590 Status error;
591
592 switch (m_state) {
593 case StateType::eStateInvalid:
594 case StateType::eStateExited:
595 case StateType::eStateCrashed:
596 case StateType::eStateDetached:
597 case StateType::eStateUnloaded:
598 // Nothing to do - the process is already dead.
599 LLDB_LOG(log, "ignored for PID {0} due to current state: {1}", GetID(),
600 StateAsCString(m_state));
601 return error;
602
603 case StateType::eStateConnected:
604 case StateType::eStateAttaching:
605 case StateType::eStateLaunching:
606 case StateType::eStateStopped:
607 case StateType::eStateRunning:
608 case StateType::eStateStepping:
609 case StateType::eStateSuspended:
610 // We can try to kill a process in these states.
611 break;
612 }
613
614 if (kill(pid: GetID(), SIGKILL) != 0) {
615 error = Status::FromErrno();
616 return error;
617 }
618
619 return error;
620}
621
622Status NativeProcessNetBSD::GetMemoryRegionInfo(lldb::addr_t load_addr,
623 MemoryRegionInfo &range_info) {
624
625 if (m_supports_mem_region == LazyBool::eLazyBoolNo) {
626 // We're done.
627 return Status::FromErrorString(str: "unsupported");
628 }
629
630 Status error = PopulateMemoryRegionCache();
631 if (error.Fail()) {
632 return error;
633 }
634
635 lldb::addr_t prev_base_address = 0;
636 // FIXME start by finding the last region that is <= target address using
637 // binary search. Data is sorted.
638 // There can be a ton of regions on pthreads apps with lots of threads.
639 for (auto it = m_mem_region_cache.begin(); it != m_mem_region_cache.end();
640 ++it) {
641 MemoryRegionInfo &proc_entry_info = it->first;
642 // Sanity check assumption that memory map entries are ascending.
643 assert((proc_entry_info.GetRange().GetRangeBase() >= prev_base_address) &&
644 "descending memory map entries detected, unexpected");
645 prev_base_address = proc_entry_info.GetRange().GetRangeBase();
646 UNUSED_IF_ASSERT_DISABLED(prev_base_address);
647 // If the target address comes before this entry, indicate distance to next
648 // region.
649 if (load_addr < proc_entry_info.GetRange().GetRangeBase()) {
650 range_info.GetRange().SetRangeBase(load_addr);
651 range_info.GetRange().SetByteSize(
652 proc_entry_info.GetRange().GetRangeBase() - load_addr);
653 range_info.SetReadable(MemoryRegionInfo::OptionalBool::eNo);
654 range_info.SetWritable(MemoryRegionInfo::OptionalBool::eNo);
655 range_info.SetExecutable(MemoryRegionInfo::OptionalBool::eNo);
656 range_info.SetMapped(MemoryRegionInfo::OptionalBool::eNo);
657 return error;
658 } else if (proc_entry_info.GetRange().Contains(r: load_addr)) {
659 // The target address is within the memory region we're processing here.
660 range_info = proc_entry_info;
661 return error;
662 }
663 // The target memory address comes somewhere after the region we just
664 // parsed.
665 }
666 // If we made it here, we didn't find an entry that contained the given
667 // address. Return the load_addr as start and the amount of bytes betwwen
668 // load address and the end of the memory as size.
669 range_info.GetRange().SetRangeBase(load_addr);
670 range_info.GetRange().SetRangeEnd(LLDB_INVALID_ADDRESS);
671 range_info.SetReadable(MemoryRegionInfo::OptionalBool::eNo);
672 range_info.SetWritable(MemoryRegionInfo::OptionalBool::eNo);
673 range_info.SetExecutable(MemoryRegionInfo::OptionalBool::eNo);
674 range_info.SetMapped(MemoryRegionInfo::OptionalBool::eNo);
675 return error;
676}
677
678Status NativeProcessNetBSD::PopulateMemoryRegionCache() {
679 Log *log = GetLog(mask: POSIXLog::Process);
680 // If our cache is empty, pull the latest. There should always be at least
681 // one memory region if memory region handling is supported.
682 if (!m_mem_region_cache.empty()) {
683 LLDB_LOG(log, "reusing {0} cached memory region entries",
684 m_mem_region_cache.size());
685 return Status();
686 }
687
688 struct kinfo_vmentry *vm;
689 size_t count, i;
690 vm = kinfo_getvmmap(GetID(), &count);
691 if (vm == NULL) {
692 m_supports_mem_region = LazyBool::eLazyBoolNo;
693 Status error;
694 error = Status::FromErrorString(str: "not supported");
695 return error;
696 }
697 for (i = 0; i < count; i++) {
698 MemoryRegionInfo info;
699 info.Clear();
700 info.GetRange().SetRangeBase(vm[i].kve_start);
701 info.GetRange().SetRangeEnd(vm[i].kve_end);
702 info.SetMapped(MemoryRegionInfo::OptionalBool::eYes);
703
704 if (vm[i].kve_protection & VM_PROT_READ)
705 info.SetReadable(MemoryRegionInfo::OptionalBool::eYes);
706 else
707 info.SetReadable(MemoryRegionInfo::OptionalBool::eNo);
708
709 if (vm[i].kve_protection & VM_PROT_WRITE)
710 info.SetWritable(MemoryRegionInfo::OptionalBool::eYes);
711 else
712 info.SetWritable(MemoryRegionInfo::OptionalBool::eNo);
713
714 if (vm[i].kve_protection & VM_PROT_EXECUTE)
715 info.SetExecutable(MemoryRegionInfo::OptionalBool::eYes);
716 else
717 info.SetExecutable(MemoryRegionInfo::OptionalBool::eNo);
718
719 if (vm[i].kve_path[0])
720 info.SetName(vm[i].kve_path);
721
722 m_mem_region_cache.emplace_back(args&: info,
723 args: FileSpec(info.GetName().GetCString()));
724 }
725 free(ptr: vm);
726
727 if (m_mem_region_cache.empty()) {
728 // No entries after attempting to read them. This shouldn't happen. Assume
729 // we don't support map entries.
730 LLDB_LOG(log, "failed to find any vmmap entries, assuming no support "
731 "for memory region metadata retrieval");
732 m_supports_mem_region = LazyBool::eLazyBoolNo;
733 Status error;
734 error = Status::FromErrorString(str: "not supported");
735 return error;
736 }
737 LLDB_LOG(log, "read {0} memory region entries from process {1}",
738 m_mem_region_cache.size(), GetID());
739 // We support memory retrieval, remember that.
740 m_supports_mem_region = LazyBool::eLazyBoolYes;
741 return Status();
742}
743
744lldb::addr_t NativeProcessNetBSD::GetSharedLibraryInfoAddress() {
745 // punt on this for now
746 return LLDB_INVALID_ADDRESS;
747}
748
749size_t NativeProcessNetBSD::UpdateThreads() { return m_threads.size(); }
750
751Status NativeProcessNetBSD::SetBreakpoint(lldb::addr_t addr, uint32_t size,
752 bool hardware) {
753 if (hardware)
754 return Status::FromErrorString(
755 str: "NativeProcessNetBSD does not support hardware breakpoints");
756 else
757 return SetSoftwareBreakpoint(addr, size_hint: size);
758}
759
760Status NativeProcessNetBSD::GetLoadedModuleFileSpec(const char *module_path,
761 FileSpec &file_spec) {
762 Status error = PopulateMemoryRegionCache();
763 if (error.Fail())
764 return error;
765
766 FileSpec module_file_spec(module_path);
767 FileSystem::Instance().Resolve(file_spec&: module_file_spec);
768
769 file_spec.Clear();
770 for (const auto &it : m_mem_region_cache) {
771 if (it.second.GetFilename() == module_file_spec.GetFilename()) {
772 file_spec = it.second;
773 return Status();
774 }
775 }
776 return Status::FromErrorStringWithFormat(
777 format: "Module file (%s) not found in process' memory map!",
778 module_file_spec.GetFilename().AsCString());
779}
780
781Status NativeProcessNetBSD::GetFileLoadAddress(const llvm::StringRef &file_name,
782 lldb::addr_t &load_addr) {
783 load_addr = LLDB_INVALID_ADDRESS;
784 Status error = PopulateMemoryRegionCache();
785 if (error.Fail())
786 return error;
787
788 FileSpec file(file_name);
789 for (const auto &it : m_mem_region_cache) {
790 if (it.second == file) {
791 load_addr = it.first.GetRange().GetRangeBase();
792 return Status();
793 }
794 }
795 return Status::FromErrorStringWithFormat(format: "No load address found for file %s.",
796 file_name.str().c_str());
797}
798
799void NativeProcessNetBSD::SigchldHandler() {
800 Log *log = GetLog(mask: POSIXLog::Process);
801 int status;
802 ::pid_t wait_pid = llvm::sys::RetryAfterSignal(-1, waitpid, GetID(), &status,
803 WALLSIG | WNOHANG);
804
805 if (wait_pid == 0)
806 return;
807
808 if (wait_pid == -1) {
809 Status error(errno, eErrorTypePOSIX);
810 LLDB_LOG(log, "waitpid ({0}, &status, _) failed: {1}", GetID(), error);
811 return;
812 }
813
814 WaitStatus wait_status = WaitStatus::Decode(wstatus: status);
815 bool exited = wait_status.type == WaitStatus::Exit ||
816 (wait_status.type == WaitStatus::Signal &&
817 wait_pid == static_cast<::pid_t>(GetID()));
818
819 LLDB_LOG(log,
820 "waitpid ({0}, &status, _) => pid = {1}, status = {2}, exited = {3}",
821 GetID(), wait_pid, status, exited);
822
823 if (exited)
824 MonitorExited(pid: wait_pid, status: wait_status);
825 else {
826 assert(wait_status.type == WaitStatus::Stop);
827 MonitorCallback(pid: wait_pid, signal: wait_status.status);
828 }
829}
830
831bool NativeProcessNetBSD::HasThreadNoLock(lldb::tid_t thread_id) {
832 for (const auto &thread : m_threads) {
833 assert(thread && "thread list should not contain NULL threads");
834 if (thread->GetID() == thread_id) {
835 // We have this thread.
836 return true;
837 }
838 }
839
840 // We don't have this thread.
841 return false;
842}
843
844NativeThreadNetBSD &NativeProcessNetBSD::AddThread(lldb::tid_t thread_id) {
845 Log *log = GetLog(mask: POSIXLog::Thread);
846 LLDB_LOG(log, "pid {0} adding thread with tid {1}", GetID(), thread_id);
847
848 assert(thread_id > 0);
849 assert(!HasThreadNoLock(thread_id) &&
850 "attempted to add a thread by id that already exists");
851
852 // If this is the first thread, save it as the current thread
853 if (m_threads.empty())
854 SetCurrentThreadID(thread_id);
855
856 m_threads.push_back(x: std::make_unique<NativeThreadNetBSD>(args&: *this, args&: thread_id));
857 return static_cast<NativeThreadNetBSD &>(*m_threads.back());
858}
859
860void NativeProcessNetBSD::RemoveThread(lldb::tid_t thread_id) {
861 Log *log = GetLog(mask: POSIXLog::Thread);
862 LLDB_LOG(log, "pid {0} removing thread with tid {1}", GetID(), thread_id);
863
864 assert(thread_id > 0);
865 assert(HasThreadNoLock(thread_id) &&
866 "attempted to remove a thread that does not exist");
867
868 for (auto it = m_threads.begin(); it != m_threads.end(); ++it) {
869 if ((*it)->GetID() == thread_id) {
870 m_threads.erase(position: it);
871 break;
872 }
873 }
874}
875
876Status NativeProcessNetBSD::Attach() {
877 // Attach to the requested process.
878 // An attach will cause the thread to stop with a SIGSTOP.
879 Status status = PtraceWrapper(PT_ATTACH, pid: m_pid);
880 if (status.Fail())
881 return status;
882
883 int wstatus;
884 // Need to use WALLSIG otherwise we receive an error with errno=ECHLD At this
885 // point we should have a thread stopped if waitpid succeeds.
886 if ((wstatus = llvm::sys::RetryAfterSignal(-1, waitpid, m_pid, nullptr,
887 WALLSIG)) < 0)
888 return Status(errno, eErrorTypePOSIX);
889
890 // Initialize threads and tracing status
891 // NB: this needs to be called before we set thread state
892 status = SetupTrace();
893 if (status.Fail())
894 return status;
895
896 for (const auto &thread : m_threads)
897 static_cast<NativeThreadNetBSD &>(*thread).SetStoppedBySignal(SIGSTOP);
898
899 // Let our process instance know the thread has stopped.
900 SetCurrentThreadID(m_threads.front()->GetID());
901 SetState(state: StateType::eStateStopped, notify_delegates: false);
902 return Status();
903}
904
905Status NativeProcessNetBSD::ReadMemory(lldb::addr_t addr, void *buf,
906 size_t size, size_t &bytes_read) {
907 unsigned char *dst = static_cast<unsigned char *>(buf);
908 struct ptrace_io_desc io;
909
910 Log *log = GetLog(mask: POSIXLog::Memory);
911 LLDB_LOG(log, "addr = {0}, buf = {1}, size = {2}", addr, buf, size);
912
913 bytes_read = 0;
914 io.piod_op = PIOD_READ_D;
915 io.piod_len = size;
916
917 do {
918 io.piod_offs = (void *)(addr + bytes_read);
919 io.piod_addr = dst + bytes_read;
920
921 Status error = NativeProcessNetBSD::PtraceWrapper(req: PT_IO, pid: GetID(), addr: &io);
922 if (error.Fail() || io.piod_len == 0)
923 return error;
924
925 bytes_read += io.piod_len;
926 io.piod_len = size - bytes_read;
927 } while (bytes_read < size);
928
929 return Status();
930}
931
932Status NativeProcessNetBSD::WriteMemory(lldb::addr_t addr, const void *buf,
933 size_t size, size_t &bytes_written) {
934 const unsigned char *src = static_cast<const unsigned char *>(buf);
935 Status error;
936 struct ptrace_io_desc io;
937
938 Log *log = GetLog(mask: POSIXLog::Memory);
939 LLDB_LOG(log, "addr = {0}, buf = {1}, size = {2}", addr, buf, size);
940
941 bytes_written = 0;
942 io.piod_op = PIOD_WRITE_D;
943 io.piod_len = size;
944
945 do {
946 io.piod_addr =
947 const_cast<void *>(static_cast<const void *>(src + bytes_written));
948 io.piod_offs = (void *)(addr + bytes_written);
949
950 Status error = NativeProcessNetBSD::PtraceWrapper(req: PT_IO, pid: GetID(), addr: &io);
951 if (error.Fail() || io.piod_len == 0)
952 return error;
953
954 bytes_written += io.piod_len;
955 io.piod_len = size - bytes_written;
956 } while (bytes_written < size);
957
958 return error;
959}
960
961llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
962NativeProcessNetBSD::GetAuxvData() const {
963 /*
964 * ELF_AUX_ENTRIES is currently restricted to kernel
965 * (<sys/exec_elf.h> r. 1.155 specifies 15)
966 *
967 * ptrace(2) returns the whole AUXV including extra fiels after AT_NULL this
968 * information isn't needed.
969 */
970 size_t auxv_size = 100 * sizeof(AuxInfo);
971
972 ErrorOr<std::unique_ptr<WritableMemoryBuffer>> buf =
973 llvm::WritableMemoryBuffer::getNewMemBuffer(Size: auxv_size);
974
975 struct ptrace_io_desc io;
976 io.piod_op = PIOD_READ_AUXV;
977 io.piod_offs = 0;
978 io.piod_addr = static_cast<void *>(buf.get()->getBufferStart());
979 io.piod_len = auxv_size;
980
981 Status error = NativeProcessNetBSD::PtraceWrapper(req: PT_IO, pid: GetID(), addr: &io);
982
983 if (error.Fail())
984 return std::error_code(error.GetError(), std::generic_category());
985
986 if (io.piod_len < 1)
987 return std::error_code(ECANCELED, std::generic_category());
988
989 return std::move(buf);
990}
991
992Status NativeProcessNetBSD::SetupTrace() {
993 // Enable event reporting
994 ptrace_event_t events;
995 Status status =
996 PtraceWrapper(req: PT_GET_EVENT_MASK, pid: GetID(), addr: &events, data: sizeof(events));
997 if (status.Fail())
998 return status;
999 // TODO: PTRACE_POSIX_SPAWN?
1000 events.pe_set_event |= PTRACE_LWP_CREATE | PTRACE_LWP_EXIT | PTRACE_FORK |
1001 PTRACE_VFORK | PTRACE_VFORK_DONE;
1002 status = PtraceWrapper(req: PT_SET_EVENT_MASK, pid: GetID(), addr: &events, data: sizeof(events));
1003 if (status.Fail())
1004 return status;
1005
1006 return ReinitializeThreads();
1007}
1008
1009Status NativeProcessNetBSD::ReinitializeThreads() {
1010 // Clear old threads
1011 m_threads.clear();
1012
1013 // Initialize new thread
1014#ifdef PT_LWPSTATUS
1015 struct ptrace_lwpstatus info = {};
1016 int op = PT_LWPNEXT;
1017#else
1018 struct ptrace_lwpinfo info = {};
1019 int op = PT_LWPINFO;
1020#endif
1021
1022 Status error = PtraceWrapper(req: op, pid: GetID(), addr: &info, data: sizeof(info));
1023
1024 if (error.Fail()) {
1025 return error;
1026 }
1027 // Reinitialize from scratch threads and register them in process
1028 while (info.pl_lwpid != 0) {
1029 AddThread(thread_id: info.pl_lwpid);
1030 error = PtraceWrapper(req: op, pid: GetID(), addr: &info, data: sizeof(info));
1031 if (error.Fail()) {
1032 return error;
1033 }
1034 }
1035
1036 return error;
1037}
1038
1039void NativeProcessNetBSD::MonitorClone(::pid_t child_pid, bool is_vfork,
1040 NativeThreadNetBSD &parent_thread) {
1041 Log *log = GetLog(mask: POSIXLog::Process);
1042 LLDB_LOG(log, "clone, child_pid={0}", child_pid);
1043
1044 int status;
1045 ::pid_t wait_pid =
1046 llvm::sys::RetryAfterSignal(Fail: -1, F&: ::waitpid, As: child_pid, As: &status, As: 0);
1047 if (wait_pid != child_pid) {
1048 LLDB_LOG(log,
1049 "waiting for pid {0} failed. Assuming the pid has "
1050 "disappeared in the meantime",
1051 child_pid);
1052 return;
1053 }
1054 if (WIFEXITED(status)) {
1055 LLDB_LOG(log,
1056 "waiting for pid {0} returned an 'exited' event. Not "
1057 "tracking it.",
1058 child_pid);
1059 return;
1060 }
1061
1062 ptrace_siginfo_t info;
1063 const auto siginfo_err =
1064 PtraceWrapper(req: PT_GET_SIGINFO, pid: child_pid, addr: &info, data: sizeof(info));
1065 if (siginfo_err.Fail()) {
1066 LLDB_LOG(log, "PT_GET_SIGINFO failed {0}", siginfo_err);
1067 return;
1068 }
1069 assert(info.psi_lwpid >= 0);
1070 lldb::tid_t child_tid = info.psi_lwpid;
1071
1072 std::unique_ptr<NativeProcessNetBSD> child_process{
1073 new NativeProcessNetBSD(static_cast<::pid_t>(child_pid), m_terminal_fd,
1074 m_delegate, m_arch, m_main_loop)};
1075 if (!is_vfork)
1076 child_process->m_software_breakpoints = m_software_breakpoints;
1077
1078 Extension expected_ext = is_vfork ? Extension::vfork : Extension::fork;
1079 if ((m_enabled_extensions & expected_ext) == expected_ext) {
1080 child_process->SetupTrace();
1081 for (const auto &thread : child_process->m_threads)
1082 static_cast<NativeThreadNetBSD &>(*thread).SetStoppedBySignal(SIGSTOP);
1083 child_process->SetState(state: StateType::eStateStopped, notify_delegates: false);
1084
1085 m_delegate.NewSubprocess(parent_process: this, child_process: std::move(child_process));
1086 if (is_vfork)
1087 parent_thread.SetStoppedByVFork(child_pid, child_tid);
1088 else
1089 parent_thread.SetStoppedByFork(child_pid, child_tid);
1090 SetState(state: StateType::eStateStopped, notify_delegates: true);
1091 } else {
1092 child_process->Detach();
1093 Status pt_error =
1094 PtraceWrapper(PT_CONTINUE, pid: GetID(), addr: reinterpret_cast<void *>(1), data: 0);
1095 if (pt_error.Fail()) {
1096 LLDB_LOG_ERROR(log, std::move(pt_error.ToError()),
1097 "unable to resume parent process {1}: {0}", GetID());
1098 SetState(state: StateType::eStateInvalid);
1099 }
1100 }
1101}
1102
1103llvm::Expected<std::string>
1104NativeProcessNetBSD::SaveCore(llvm::StringRef path_hint) {
1105 llvm::SmallString<128> path{path_hint};
1106 Status error;
1107
1108 // Try with the suggested path first.
1109 if (!path.empty()) {
1110 error = PtraceWrapper(req: PT_DUMPCORE, pid: GetID(), addr: path.data(), data: path.size());
1111 if (!error.Fail())
1112 return path.str().str();
1113
1114 // If the request errored, fall back to a generic temporary file.
1115 }
1116
1117 if (std::error_code errc =
1118 llvm::sys::fs::createTemporaryFile(Prefix: "lldb", Suffix: "core", ResultPath&: path))
1119 return llvm::createStringError(EC: errc, S: "Unable to create a temporary file");
1120
1121 error = PtraceWrapper(PT_DUMPCORE, GetID(), path.data(), path.size());
1122 if (error.Fail())
1123 return error.ToError();
1124 return path.str().str();
1125}
1126

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source code of lldb/source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp