xref: /llvm-project/lldb/source/Plugins/Process/elf-core/ThreadElfCore.cpp (revision 911a6f2fcc719c46b5b392823473ba0bb5b1f4e1)
1 //===-- ThreadElfCore.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 "lldb/Target/RegisterContext.h"
10 #include "lldb/Target/StopInfo.h"
11 #include "lldb/Target/Target.h"
12 #include "lldb/Target/Unwind.h"
13 #include "lldb/Utility/DataExtractor.h"
14 #include "lldb/Utility/LLDBLog.h"
15 #include "lldb/Utility/Log.h"
16 #include "lldb/Utility/ProcessInfo.h"
17 
18 #include "Plugins/Process/Utility/RegisterContextFreeBSD_i386.h"
19 #include "Plugins/Process/Utility/RegisterContextFreeBSD_mips64.h"
20 #include "Plugins/Process/Utility/RegisterContextFreeBSD_powerpc.h"
21 #include "Plugins/Process/Utility/RegisterContextFreeBSD_x86_64.h"
22 #include "Plugins/Process/Utility/RegisterContextLinux_i386.h"
23 #include "Plugins/Process/Utility/RegisterContextLinux_s390x.h"
24 #include "Plugins/Process/Utility/RegisterContextLinux_x86_64.h"
25 #include "Plugins/Process/Utility/RegisterContextNetBSD_i386.h"
26 #include "Plugins/Process/Utility/RegisterContextNetBSD_x86_64.h"
27 #include "Plugins/Process/Utility/RegisterContextOpenBSD_i386.h"
28 #include "Plugins/Process/Utility/RegisterContextOpenBSD_x86_64.h"
29 #include "Plugins/Process/Utility/RegisterInfoPOSIX_arm.h"
30 #include "Plugins/Process/Utility/RegisterInfoPOSIX_arm64.h"
31 #include "Plugins/Process/Utility/RegisterInfoPOSIX_ppc64le.h"
32 #include "ProcessElfCore.h"
33 #include "RegisterContextLinuxCore_x86_64.h"
34 #include "RegisterContextPOSIXCore_arm.h"
35 #include "RegisterContextPOSIXCore_arm64.h"
36 #include "RegisterContextPOSIXCore_loongarch64.h"
37 #include "RegisterContextPOSIXCore_mips64.h"
38 #include "RegisterContextPOSIXCore_powerpc.h"
39 #include "RegisterContextPOSIXCore_ppc64le.h"
40 #include "RegisterContextPOSIXCore_riscv64.h"
41 #include "RegisterContextPOSIXCore_s390x.h"
42 #include "RegisterContextPOSIXCore_x86_64.h"
43 #include "ThreadElfCore.h"
44 
45 #include <memory>
46 
47 using namespace lldb;
48 using namespace lldb_private;
49 
50 // Construct a Thread object with given data
51 ThreadElfCore::ThreadElfCore(Process &process, const ThreadData &td)
52     : Thread(process, td.tid), m_thread_name(td.name), m_thread_reg_ctx_sp(),
53       m_signo(td.signo), m_code(td.code), m_gpregset_data(td.gpregset),
54       m_notes(td.notes) {}
55 
56 ThreadElfCore::~ThreadElfCore() { DestroyThread(); }
57 
58 void ThreadElfCore::RefreshStateAfterStop() {
59   GetRegisterContext()->InvalidateIfNeeded(false);
60 }
61 
62 RegisterContextSP ThreadElfCore::GetRegisterContext() {
63   if (!m_reg_context_sp) {
64     m_reg_context_sp = CreateRegisterContextForFrame(nullptr);
65   }
66   return m_reg_context_sp;
67 }
68 
69 RegisterContextSP
70 ThreadElfCore::CreateRegisterContextForFrame(StackFrame *frame) {
71   RegisterContextSP reg_ctx_sp;
72   uint32_t concrete_frame_idx = 0;
73   Log *log = GetLog(LLDBLog::Thread);
74 
75   if (frame)
76     concrete_frame_idx = frame->GetConcreteFrameIndex();
77 
78   bool is_linux = false;
79   if (concrete_frame_idx == 0) {
80     if (m_thread_reg_ctx_sp)
81       return m_thread_reg_ctx_sp;
82 
83     ProcessElfCore *process = static_cast<ProcessElfCore *>(GetProcess().get());
84     ArchSpec arch = process->GetArchitecture();
85     RegisterInfoInterface *reg_interface = nullptr;
86 
87     switch (arch.GetTriple().getOS()) {
88     case llvm::Triple::FreeBSD: {
89       switch (arch.GetMachine()) {
90       case llvm::Triple::aarch64:
91       case llvm::Triple::arm:
92         break;
93       case llvm::Triple::ppc:
94         reg_interface = new RegisterContextFreeBSD_powerpc32(arch);
95         break;
96       case llvm::Triple::ppc64:
97         reg_interface = new RegisterContextFreeBSD_powerpc64(arch);
98         break;
99       case llvm::Triple::mips64:
100         reg_interface = new RegisterContextFreeBSD_mips64(arch);
101         break;
102       case llvm::Triple::x86:
103         reg_interface = new RegisterContextFreeBSD_i386(arch);
104         break;
105       case llvm::Triple::x86_64:
106         reg_interface = new RegisterContextFreeBSD_x86_64(arch);
107         break;
108       default:
109         break;
110       }
111       break;
112     }
113 
114     case llvm::Triple::NetBSD: {
115       switch (arch.GetMachine()) {
116       case llvm::Triple::aarch64:
117         break;
118       case llvm::Triple::x86:
119         reg_interface = new RegisterContextNetBSD_i386(arch);
120         break;
121       case llvm::Triple::x86_64:
122         reg_interface = new RegisterContextNetBSD_x86_64(arch);
123         break;
124       default:
125         break;
126       }
127       break;
128     }
129 
130     case llvm::Triple::Linux: {
131       is_linux = true;
132       switch (arch.GetMachine()) {
133       case llvm::Triple::aarch64:
134         break;
135       case llvm::Triple::ppc64le:
136         reg_interface = new RegisterInfoPOSIX_ppc64le(arch);
137         break;
138       case llvm::Triple::systemz:
139         reg_interface = new RegisterContextLinux_s390x(arch);
140         break;
141       case llvm::Triple::x86:
142         reg_interface = new RegisterContextLinux_i386(arch);
143         break;
144       case llvm::Triple::x86_64:
145         reg_interface = new RegisterContextLinux_x86_64(arch);
146         break;
147       default:
148         break;
149       }
150       break;
151     }
152 
153     case llvm::Triple::OpenBSD: {
154       switch (arch.GetMachine()) {
155       case llvm::Triple::aarch64:
156         break;
157       case llvm::Triple::x86:
158         reg_interface = new RegisterContextOpenBSD_i386(arch);
159         break;
160       case llvm::Triple::x86_64:
161         reg_interface = new RegisterContextOpenBSD_x86_64(arch);
162         break;
163       default:
164         break;
165       }
166       break;
167     }
168 
169     default:
170       break;
171     }
172 
173     if (!reg_interface && arch.GetMachine() != llvm::Triple::aarch64 &&
174         arch.GetMachine() != llvm::Triple::arm &&
175         arch.GetMachine() != llvm::Triple::loongarch64 &&
176         arch.GetMachine() != llvm::Triple::riscv64) {
177       LLDB_LOGF(log, "elf-core::%s:: Architecture(%d) or OS(%d) not supported",
178                 __FUNCTION__, arch.GetMachine(), arch.GetTriple().getOS());
179       assert(false && "Architecture or OS not supported");
180     }
181 
182     switch (arch.GetMachine()) {
183     case llvm::Triple::aarch64:
184       m_thread_reg_ctx_sp = RegisterContextCorePOSIX_arm64::Create(
185           *this, arch, m_gpregset_data, m_notes);
186       break;
187     case llvm::Triple::arm:
188       m_thread_reg_ctx_sp = std::make_shared<RegisterContextCorePOSIX_arm>(
189           *this, std::make_unique<RegisterInfoPOSIX_arm>(arch), m_gpregset_data,
190           m_notes);
191       break;
192     case llvm::Triple::loongarch64:
193       m_thread_reg_ctx_sp = RegisterContextCorePOSIX_loongarch64::Create(
194           *this, arch, m_gpregset_data, m_notes);
195       break;
196     case llvm::Triple::riscv64:
197       m_thread_reg_ctx_sp = RegisterContextCorePOSIX_riscv64::Create(
198           *this, arch, m_gpregset_data, m_notes);
199       break;
200     case llvm::Triple::mipsel:
201     case llvm::Triple::mips:
202       m_thread_reg_ctx_sp = std::make_shared<RegisterContextCorePOSIX_mips64>(
203           *this, reg_interface, m_gpregset_data, m_notes);
204       break;
205     case llvm::Triple::mips64:
206     case llvm::Triple::mips64el:
207       m_thread_reg_ctx_sp = std::make_shared<RegisterContextCorePOSIX_mips64>(
208           *this, reg_interface, m_gpregset_data, m_notes);
209       break;
210     case llvm::Triple::ppc:
211     case llvm::Triple::ppc64:
212       m_thread_reg_ctx_sp = std::make_shared<RegisterContextCorePOSIX_powerpc>(
213           *this, reg_interface, m_gpregset_data, m_notes);
214       break;
215     case llvm::Triple::ppc64le:
216       m_thread_reg_ctx_sp = std::make_shared<RegisterContextCorePOSIX_ppc64le>(
217           *this, reg_interface, m_gpregset_data, m_notes);
218       break;
219     case llvm::Triple::systemz:
220       m_thread_reg_ctx_sp = std::make_shared<RegisterContextCorePOSIX_s390x>(
221           *this, reg_interface, m_gpregset_data, m_notes);
222       break;
223     case llvm::Triple::x86:
224     case llvm::Triple::x86_64:
225       if (is_linux) {
226         m_thread_reg_ctx_sp = std::make_shared<RegisterContextLinuxCore_x86_64>(
227               *this, reg_interface, m_gpregset_data, m_notes);
228       } else {
229         m_thread_reg_ctx_sp = std::make_shared<RegisterContextCorePOSIX_x86_64>(
230               *this, reg_interface, m_gpregset_data, m_notes);
231       }
232       break;
233     default:
234       break;
235     }
236 
237     reg_ctx_sp = m_thread_reg_ctx_sp;
238   } else {
239     reg_ctx_sp = GetUnwinder().CreateRegisterContextForFrame(frame);
240   }
241   return reg_ctx_sp;
242 }
243 
244 bool ThreadElfCore::CalculateStopInfo() {
245   ProcessSP process_sp(GetProcess());
246   if (!process_sp)
247     return false;
248 
249   SetStopInfo(StopInfo::CreateStopReasonWithSignal(
250       *this, m_signo, /*description=*/nullptr, m_code));
251   return true;
252 }
253 
254 // Parse PRSTATUS from NOTE entry
255 ELFLinuxPrStatus::ELFLinuxPrStatus() {
256   memset(this, 0, sizeof(ELFLinuxPrStatus));
257 }
258 
259 size_t ELFLinuxPrStatus::GetSize(const lldb_private::ArchSpec &arch) {
260   constexpr size_t mips_linux_pr_status_size_o32 = 96;
261   constexpr size_t mips_linux_pr_status_size_n32 = 72;
262   constexpr size_t num_ptr_size_members = 10;
263   if (arch.IsMIPS()) {
264     std::string abi = arch.GetTargetABI();
265     assert(!abi.empty() && "ABI is not set");
266     if (!abi.compare("n64"))
267       return sizeof(ELFLinuxPrStatus);
268     else if (!abi.compare("o32"))
269       return mips_linux_pr_status_size_o32;
270     // N32 ABI
271     return mips_linux_pr_status_size_n32;
272   }
273   switch (arch.GetCore()) {
274   case lldb_private::ArchSpec::eCore_x86_32_i386:
275   case lldb_private::ArchSpec::eCore_x86_32_i486:
276     return 72;
277   default:
278     if (arch.GetAddressByteSize() == 8)
279       return sizeof(ELFLinuxPrStatus);
280     else
281       return sizeof(ELFLinuxPrStatus) - num_ptr_size_members * 4;
282   }
283 }
284 
285 Status ELFLinuxPrStatus::Parse(const DataExtractor &data,
286                                const ArchSpec &arch) {
287   Status error;
288   if (GetSize(arch) > data.GetByteSize()) {
289     error = Status::FromErrorStringWithFormat(
290         "NT_PRSTATUS size should be %zu, but the remaining bytes are: %" PRIu64,
291         GetSize(arch), data.GetByteSize());
292     return error;
293   }
294 
295   // Read field by field to correctly account for endianess of both the core
296   // dump and the platform running lldb.
297   offset_t offset = 0;
298   si_signo = data.GetU32(&offset);
299   si_code = data.GetU32(&offset);
300   si_errno = data.GetU32(&offset);
301 
302   pr_cursig = data.GetU16(&offset);
303   offset += 2; // pad
304 
305   pr_sigpend = data.GetAddress(&offset);
306   pr_sighold = data.GetAddress(&offset);
307 
308   pr_pid = data.GetU32(&offset);
309   pr_ppid = data.GetU32(&offset);
310   pr_pgrp = data.GetU32(&offset);
311   pr_sid = data.GetU32(&offset);
312 
313   pr_utime.tv_sec = data.GetAddress(&offset);
314   pr_utime.tv_usec = data.GetAddress(&offset);
315 
316   pr_stime.tv_sec = data.GetAddress(&offset);
317   pr_stime.tv_usec = data.GetAddress(&offset);
318 
319   pr_cutime.tv_sec = data.GetAddress(&offset);
320   pr_cutime.tv_usec = data.GetAddress(&offset);
321 
322   pr_cstime.tv_sec = data.GetAddress(&offset);
323   pr_cstime.tv_usec = data.GetAddress(&offset);
324 
325   return error;
326 }
327 
328 static struct compat_timeval
329 copy_timespecs(const ProcessInstanceInfo::timespec &oth) {
330   using sec_t = decltype(compat_timeval::tv_sec);
331   using usec_t = decltype(compat_timeval::tv_usec);
332   return {static_cast<sec_t>(oth.tv_sec), static_cast<usec_t>(oth.tv_usec)};
333 }
334 
335 std::optional<ELFLinuxPrStatus>
336 ELFLinuxPrStatus::Populate(const lldb::ThreadSP &thread_sp) {
337   ELFLinuxPrStatus prstatus{};
338   prstatus.pr_pid = thread_sp->GetID();
339   lldb::ProcessSP process_sp = thread_sp->GetProcess();
340   ProcessInstanceInfo info;
341   if (!process_sp->GetProcessInfo(info))
342     return std::nullopt;
343 
344   prstatus.pr_ppid = info.GetParentProcessID();
345   prstatus.pr_pgrp = info.GetProcessGroupID();
346   prstatus.pr_sid = info.GetProcessSessionID();
347   prstatus.pr_utime = copy_timespecs(info.GetUserTime());
348   prstatus.pr_stime = copy_timespecs(info.GetSystemTime());
349   prstatus.pr_cutime = copy_timespecs(info.GetCumulativeUserTime());
350   prstatus.pr_cstime = copy_timespecs(info.GetCumulativeSystemTime());
351   return prstatus;
352 }
353 
354 // Parse PRPSINFO from NOTE entry
355 ELFLinuxPrPsInfo::ELFLinuxPrPsInfo() {
356   memset(this, 0, sizeof(ELFLinuxPrPsInfo));
357 }
358 
359 size_t ELFLinuxPrPsInfo::GetSize(const lldb_private::ArchSpec &arch) {
360   constexpr size_t mips_linux_pr_psinfo_size_o32_n32 = 128;
361   if (arch.IsMIPS()) {
362     uint8_t address_byte_size = arch.GetAddressByteSize();
363     if (address_byte_size == 8)
364       return sizeof(ELFLinuxPrPsInfo);
365     return mips_linux_pr_psinfo_size_o32_n32;
366   }
367 
368   switch (arch.GetCore()) {
369   case lldb_private::ArchSpec::eCore_s390x_generic:
370   case lldb_private::ArchSpec::eCore_x86_64_x86_64:
371     return sizeof(ELFLinuxPrPsInfo);
372   case lldb_private::ArchSpec::eCore_x86_32_i386:
373   case lldb_private::ArchSpec::eCore_x86_32_i486:
374     return 124;
375   default:
376     return 0;
377   }
378 }
379 
380 Status ELFLinuxPrPsInfo::Parse(const DataExtractor &data,
381                                const ArchSpec &arch) {
382   Status error;
383   ByteOrder byteorder = data.GetByteOrder();
384   if (GetSize(arch) > data.GetByteSize()) {
385     error = Status::FromErrorStringWithFormat(
386         "NT_PRPSINFO size should be %zu, but the remaining bytes are: %" PRIu64,
387         GetSize(arch), data.GetByteSize());
388     return error;
389   }
390   size_t size = 0;
391   offset_t offset = 0;
392 
393   pr_state = data.GetU8(&offset);
394   pr_sname = data.GetU8(&offset);
395   pr_zomb = data.GetU8(&offset);
396   pr_nice = data.GetU8(&offset);
397   if (data.GetAddressByteSize() == 8) {
398     // Word align the next field on 64 bit.
399     offset += 4;
400   }
401 
402   pr_flag = data.GetAddress(&offset);
403 
404   if (arch.IsMIPS()) {
405     // The pr_uid and pr_gid is always 32 bit irrespective of platforms
406     pr_uid = data.GetU32(&offset);
407     pr_gid = data.GetU32(&offset);
408   } else {
409     // 16 bit on 32 bit platforms, 32 bit on 64 bit platforms
410     pr_uid = data.GetMaxU64(&offset, data.GetAddressByteSize() >> 1);
411     pr_gid = data.GetMaxU64(&offset, data.GetAddressByteSize() >> 1);
412   }
413 
414   pr_pid = data.GetU32(&offset);
415   pr_ppid = data.GetU32(&offset);
416   pr_pgrp = data.GetU32(&offset);
417   pr_sid = data.GetU32(&offset);
418 
419   size = 16;
420   data.ExtractBytes(offset, size, byteorder, pr_fname);
421   offset += size;
422 
423   size = 80;
424   data.ExtractBytes(offset, size, byteorder, pr_psargs);
425   offset += size;
426 
427   return error;
428 }
429 
430 std::optional<ELFLinuxPrPsInfo>
431 ELFLinuxPrPsInfo::Populate(const lldb::ProcessSP &process_sp) {
432   ProcessInstanceInfo info;
433   if (!process_sp->GetProcessInfo(info))
434     return std::nullopt;
435 
436   return Populate(info, process_sp->GetState());
437 }
438 
439 std::optional<ELFLinuxPrPsInfo>
440 ELFLinuxPrPsInfo::Populate(const lldb_private::ProcessInstanceInfo &info,
441                            lldb::StateType process_state) {
442   ELFLinuxPrPsInfo prpsinfo{};
443   prpsinfo.pr_pid = info.GetProcessID();
444   prpsinfo.pr_nice = info.GetPriorityValue().value_or(0);
445   prpsinfo.pr_zomb = 0;
446   if (auto zombie_opt = info.IsZombie(); zombie_opt.value_or(false)) {
447     prpsinfo.pr_zomb = 1;
448   }
449   /**
450    * In the linux kernel this comes from:
451    * state = READ_ONCE(p->__state);
452    * i = state ? ffz(~state) + 1 : 0;
453    * psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
454    *
455    * So we replicate that here. From proc_pid_stats(5)
456    * R = Running
457    * S = Sleeping on uninterrutible wait
458    * D = Waiting on uninterruptable disk sleep
459    * T = Tracing stop
460    * Z = Zombie
461    * W = Paging
462    */
463   switch (process_state) {
464   case lldb::StateType::eStateSuspended:
465     prpsinfo.pr_sname = 'S';
466     prpsinfo.pr_state = 1;
467     break;
468   case lldb::StateType::eStateStopped:
469     [[fallthrough]];
470   case lldb::StateType::eStateStepping:
471     prpsinfo.pr_sname = 'T';
472     prpsinfo.pr_state = 3;
473     break;
474   case lldb::StateType::eStateUnloaded:
475     [[fallthrough]];
476   case lldb::StateType::eStateRunning:
477     prpsinfo.pr_sname = 'R';
478     prpsinfo.pr_state = 0;
479     break;
480   default:
481     break;
482   }
483 
484   /**
485    * pr_flags is left as 0. The values (in linux) are specific
486    * to the kernel. We recover them from the proc filesystem
487    * but don't put them in ProcessInfo because it would really
488    * become very linux specific and the utility here seems pretty
489    * dubious
490    */
491 
492   if (info.EffectiveUserIDIsValid())
493     prpsinfo.pr_uid = info.GetUserID();
494 
495   if (info.EffectiveGroupIDIsValid())
496     prpsinfo.pr_gid = info.GetGroupID();
497 
498   if (info.ParentProcessIDIsValid())
499     prpsinfo.pr_ppid = info.GetParentProcessID();
500 
501   if (info.ProcessGroupIDIsValid())
502     prpsinfo.pr_pgrp = info.GetProcessGroupID();
503 
504   if (info.ProcessSessionIDIsValid())
505     prpsinfo.pr_sid = info.GetProcessSessionID();
506 
507   constexpr size_t fname_len = std::extent_v<decltype(prpsinfo.pr_fname)>;
508   static_assert(fname_len > 0, "This should always be non zero");
509   const llvm::StringRef fname = info.GetNameAsStringRef();
510   auto fname_begin = fname.begin();
511   std::copy_n(fname_begin, std::min(fname_len, fname.size()),
512               prpsinfo.pr_fname);
513   prpsinfo.pr_fname[fname_len - 1] = '\0';
514   auto args = info.GetArguments();
515   auto argentry_iterator = std::begin(args);
516   char *psargs = prpsinfo.pr_psargs;
517   char *psargs_end = std::end(prpsinfo.pr_psargs);
518   while (psargs < psargs_end && argentry_iterator != args.end()) {
519     llvm::StringRef argentry = argentry_iterator->ref();
520     size_t len =
521         std::min<size_t>(std::distance(psargs, psargs_end), argentry.size());
522     auto arg_iterator = std::begin(argentry);
523     psargs = std::copy_n(arg_iterator, len, psargs);
524     if (psargs != psargs_end)
525       *(psargs++) = ' ';
526     ++argentry_iterator;
527   }
528   *(psargs - 1) = '\0';
529   return prpsinfo;
530 }
531 
532 // Parse SIGINFO from NOTE entry
533 ELFLinuxSigInfo::ELFLinuxSigInfo() { memset(this, 0, sizeof(ELFLinuxSigInfo)); }
534 
535 size_t ELFLinuxSigInfo::GetSize(const lldb_private::ArchSpec &arch) {
536   if (arch.IsMIPS())
537     return sizeof(ELFLinuxSigInfo);
538   switch (arch.GetCore()) {
539   case lldb_private::ArchSpec::eCore_x86_64_x86_64:
540     return sizeof(ELFLinuxSigInfo);
541   case lldb_private::ArchSpec::eCore_s390x_generic:
542   case lldb_private::ArchSpec::eCore_x86_32_i386:
543   case lldb_private::ArchSpec::eCore_x86_32_i486:
544     return 12;
545   default:
546     return 0;
547   }
548 }
549 
550 Status ELFLinuxSigInfo::Parse(const DataExtractor &data, const ArchSpec &arch) {
551   Status error;
552   if (GetSize(arch) > data.GetByteSize()) {
553     error = Status::FromErrorStringWithFormat(
554         "NT_SIGINFO size should be %zu, but the remaining bytes are: %" PRIu64,
555         GetSize(arch), data.GetByteSize());
556     return error;
557   }
558 
559   // Parsing from a 32 bit ELF core file, and populating/reusing the structure
560   // properly, because the struct is for the 64 bit version
561   offset_t offset = 0;
562   si_signo = data.GetU32(&offset);
563   si_errno = data.GetU32(&offset);
564   si_code = data.GetU32(&offset);
565 
566   return error;
567 }
568