xref: /reactos/dll/win32/kernel32/client/except.c (revision 41c99aa6)
1 /*
2  * COPYRIGHT:       See COPYING in the top level directory
3  * PROJECT:         ReactOS system libraries
4  * FILE:            dll/win32/kernel32/client/except.c
5  * PURPOSE:         Exception functions
6  * PROGRAMMER:      Ariadne (ariadne@xs4all.nl)
7  *                  Modified from WINE [ Onno Hovers, (onno@stack.urc.tue.nl) ]
8  * UPDATE HISTORY:
9  *                  Created 01/11/98
10  */
11 
12 /* INCLUDES *******************************************************************/
13 
14 #include <k32.h>
15 #include <strsafe.h>
16 
17 #define NDEBUG
18 #include <debug.h>
19 
20 /*
21  * Private helper function to lookup the module name from a given address.
22  * The address can point to anywhere within the module.
23  */
24 static const char*
_module_name_from_addr(const void * addr,void ** module_start_addr,char * psz,size_t nChars,char ** module_name)25 _module_name_from_addr(const void* addr, void **module_start_addr,
26                        char* psz, size_t nChars, char** module_name)
27 {
28     MEMORY_BASIC_INFORMATION mbi;
29 
30     if ((nChars > MAXDWORD) ||
31         (VirtualQuery(addr, &mbi, sizeof(mbi)) != sizeof(mbi)) ||
32         !GetModuleFileNameA((HMODULE)mbi.AllocationBase, psz, (DWORD)nChars))
33     {
34         psz[0] = '\0';
35         *module_name = psz;
36         *module_start_addr = 0;
37     }
38     else
39     {
40         char* s1 = strrchr(psz, '\\'), *s2 = strrchr(psz, '/');
41         if (s2 && !s1)
42             s1 = s2;
43         else if (s1 && s2 && s1 < s2)
44             s1 = s2;
45 
46         if (!s1)
47             s1 = psz;
48         else
49             s1++;
50 
51         *module_name = s1;
52         *module_start_addr = (void *)mbi.AllocationBase;
53     }
54     return psz;
55 }
56 
57 
58 static VOID
_dump_context(PCONTEXT pc)59 _dump_context(PCONTEXT pc)
60 {
61 #ifdef _M_IX86
62     /*
63      * Print out the CPU registers
64      */
65     DbgPrint("CS:EIP %x:%x\n", pc->SegCs&0xffff, pc->Eip );
66     DbgPrint("DS %x ES %x FS %x GS %x\n", pc->SegDs&0xffff, pc->SegEs&0xffff,
67              pc->SegFs&0xffff, pc->SegGs&0xfff);
68     DbgPrint("EAX: %.8x   EBX: %.8x   ECX: %.8x\n", pc->Eax, pc->Ebx, pc->Ecx);
69     DbgPrint("EDX: %.8x   EBP: %.8x   ESI: %.8x   ESP: %.8x\n", pc->Edx,
70              pc->Ebp, pc->Esi, pc->Esp);
71     DbgPrint("EDI: %.8x   EFLAGS: %.8x\n", pc->Edi, pc->EFlags);
72 #elif defined(_M_AMD64)
73     DbgPrint("CS:RIP %x:%I64x\n", pc->SegCs&0xffff, pc->Rip );
74     DbgPrint("DS %x ES %x FS %x GS %x\n", pc->SegDs&0xffff, pc->SegEs&0xffff,
75              pc->SegFs&0xffff, pc->SegGs&0xfff);
76     DbgPrint("RAX: %I64x   RBX: %I64x   RCX: %I64x RDI: %I64x\n", pc->Rax, pc->Rbx, pc->Rcx, pc->Rdi);
77     DbgPrint("RDX: %I64x   RBP: %I64x   RSI: %I64x   RSP: %I64x\n", pc->Rdx, pc->Rbp, pc->Rsi, pc->Rsp);
78     DbgPrint("R8: %I64x   R9: %I64x   R10: %I64x   R11: %I64x\n", pc->R8, pc->R9, pc->R10, pc->R11);
79     DbgPrint("R12: %I64x   R13: %I64x   R14: %I64x   R15: %I64x\n", pc->R12, pc->R13, pc->R14, pc->R15);
80     DbgPrint("EFLAGS: %.8x\n", pc->EFlags);
81 #elif defined(_M_ARM)
82     DbgPrint("PC:  %08lx   LR:  %08lx   SP:  %08lx\n", pc->Pc);
83     DbgPrint("R0:  %08lx   R1:  %08lx   R2:  %08lx   R3:  %08lx\n", pc->R0, pc->R1, pc->R2, pc->R3);
84     DbgPrint("R4:  %08lx   R5:  %08lx   R6:  %08lx   R7:  %08lx\n", pc->R4, pc->R5, pc->R6, pc->R7);
85     DbgPrint("R8:  %08lx   R9:  %08lx   R10: %08lx   R11: %08lx\n", pc->R8, pc->R9, pc->R10, pc->R11);
86     DbgPrint("R12: %08lx   CPSR: %08lx  FPSCR: %08lx\n", pc->R12, pc->Cpsr, pc->R1, pc->Fpscr, pc->R3);
87 #else
88     #error "Unknown architecture"
89 #endif
90 }
91 
92 static VOID
PrintStackTrace(IN PEXCEPTION_POINTERS ExceptionInfo)93 PrintStackTrace(IN PEXCEPTION_POINTERS ExceptionInfo)
94 {
95     PVOID StartAddr;
96     CHAR szMod[128] = "", *szModFile;
97     PEXCEPTION_RECORD ExceptionRecord = ExceptionInfo->ExceptionRecord;
98     PCONTEXT ContextRecord = ExceptionInfo->ContextRecord;
99 
100     /* Print a stack trace */
101     DbgPrint("Unhandled exception\n");
102     DbgPrint("ExceptionCode:    %8x\n", ExceptionRecord->ExceptionCode);
103 
104     if (ExceptionRecord->ExceptionCode == STATUS_ACCESS_VIOLATION &&
105         ExceptionRecord->NumberParameters == 2)
106     {
107         DbgPrint("Faulting Address: %p\n", (PVOID)ExceptionRecord->ExceptionInformation[1]);
108     }
109 
110     /* Trace the wine special error and show the modulename and functionname */
111     if (ExceptionRecord->ExceptionCode == 0x80000100 /* EXCEPTION_WINE_STUB */ &&
112         ExceptionRecord->NumberParameters == 2)
113     {
114         DbgPrint("Missing function: %s!%s\n", (PSZ)ExceptionRecord->ExceptionInformation[0], (PSZ)ExceptionRecord->ExceptionInformation[1]);
115     }
116 
117     _dump_context(ContextRecord);
118     _module_name_from_addr(ExceptionRecord->ExceptionAddress, &StartAddr, szMod, sizeof(szMod), &szModFile);
119     DbgPrint("Address:\n<%s:%x> (%s@%x)\n",
120              szModFile,
121              (ULONG_PTR)ExceptionRecord->ExceptionAddress - (ULONG_PTR)StartAddr,
122              szMod,
123              StartAddr);
124 #ifdef _M_IX86
125     DbgPrint("Frames:\n");
126 
127     _SEH2_TRY
128     {
129         UINT i;
130         PULONG Frame = (PULONG)ContextRecord->Ebp;
131 
132         for (i = 0; Frame[1] != 0 && Frame[1] != 0xdeadbeef && i < 128; i++)
133         {
134             if (IsBadReadPtr((PVOID)Frame[1], 4))
135             {
136                 DbgPrint("<%s:%x>\n", "[invalid address]", Frame[1]);
137             }
138             else
139             {
140                 _module_name_from_addr((const void*)Frame[1], &StartAddr,
141                                        szMod, sizeof(szMod), &szModFile);
142                 DbgPrint("<%s:%x> (%s@%x)\n",
143                          szModFile,
144                          (ULONG_PTR)Frame[1] - (ULONG_PTR)StartAddr,
145                          szMod,
146                          StartAddr);
147             }
148 
149             if (IsBadReadPtr((PVOID)Frame[0], sizeof(*Frame) * 2))
150                 break;
151 
152             Frame = (PULONG)Frame[0];
153         }
154     }
155     _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
156     {
157         DbgPrint("<error dumping stack trace: 0x%x>\n", _SEH2_GetExceptionCode());
158     }
159     _SEH2_END;
160 #endif
161 }
162 
163 /* GLOBALS ********************************************************************/
164 
165 LPTOP_LEVEL_EXCEPTION_FILTER GlobalTopLevelExceptionFilter;
166 DWORD g_dwLastErrorToBreakOn;
167 
168 /* FUNCTIONS ******************************************************************/
169 
170 LONG
171 WINAPI
BasepCheckForReadOnlyResource(IN PVOID Ptr)172 BasepCheckForReadOnlyResource(IN PVOID Ptr)
173 {
174     PVOID Data;
175     ULONG Size, OldProtect;
176     SIZE_T Size2;
177     MEMORY_BASIC_INFORMATION mbi;
178     NTSTATUS Status;
179     LONG Ret = EXCEPTION_CONTINUE_SEARCH;
180 
181     /* Check if it was an attempt to write to a read-only image section! */
182     Status = NtQueryVirtualMemory(NtCurrentProcess(),
183                                   Ptr,
184                                   MemoryBasicInformation,
185                                   &mbi,
186                                   sizeof(mbi),
187                                   NULL);
188     if (NT_SUCCESS(Status) &&
189         mbi.Protect == PAGE_READONLY && mbi.Type == MEM_IMAGE)
190     {
191         /* Attempt to treat it as a resource section. We need to
192            use SEH here because we don't know if it's actually a
193            resource mapping */
194         _SEH2_TRY
195         {
196             Data = RtlImageDirectoryEntryToData(mbi.AllocationBase,
197                                                 TRUE,
198                                                 IMAGE_DIRECTORY_ENTRY_RESOURCE,
199                                                 &Size);
200 
201             if (Data != NULL &&
202                 (ULONG_PTR)Ptr >= (ULONG_PTR)Data &&
203                 (ULONG_PTR)Ptr < (ULONG_PTR)Data + Size)
204             {
205                 /* The user tried to write into the resources. Make the page
206                    writable... */
207                 Size2 = 1;
208                 Status = NtProtectVirtualMemory(NtCurrentProcess(),
209                                                 &Ptr,
210                                                 &Size2,
211                                                 PAGE_READWRITE,
212                                                 &OldProtect);
213                 if (NT_SUCCESS(Status))
214                 {
215                     Ret = EXCEPTION_CONTINUE_EXECUTION;
216                 }
217             }
218         }
219         _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
220         {
221         }
222         _SEH2_END;
223     }
224 
225     return Ret;
226 }
227 
228 UINT
229 WINAPI
GetErrorMode(VOID)230 GetErrorMode(VOID)
231 {
232     NTSTATUS Status;
233     UINT ErrMode;
234 
235     /* Query the current setting */
236     Status = NtQueryInformationProcess(NtCurrentProcess(),
237                                        ProcessDefaultHardErrorMode,
238                                        &ErrMode,
239                                        sizeof(ErrMode),
240                                        NULL);
241     if (!NT_SUCCESS(Status))
242     {
243         /* Fail if we couldn't query */
244         BaseSetLastNTError(Status);
245         return 0;
246     }
247 
248     /* Check if NOT failing critical errors was requested */
249     if (ErrMode & SEM_FAILCRITICALERRORS)
250     {
251         /* Mask it out, since the native API works differently */
252         ErrMode &= ~SEM_FAILCRITICALERRORS;
253     }
254     else
255     {
256         /* OR it if the caller didn't, due to different native semantics */
257         ErrMode |= SEM_FAILCRITICALERRORS;
258     }
259 
260     /* Return the mode */
261     return ErrMode;
262 }
263 
264 /*
265  * @implemented
266  */
267 LONG
268 WINAPI
UnhandledExceptionFilter(IN PEXCEPTION_POINTERS ExceptionInfo)269 UnhandledExceptionFilter(IN PEXCEPTION_POINTERS ExceptionInfo)
270 {
271     static UNICODE_STRING AeDebugKey =
272         RTL_CONSTANT_STRING(L"\\Registry\\Machine\\" REGSTR_PATH_AEDEBUG);
273 
274     static BOOLEAN IsSecondChance = FALSE;
275 
276     /* Exception data */
277     NTSTATUS Status;
278     PEXCEPTION_RECORD ExceptionRecord = ExceptionInfo->ExceptionRecord;
279     LPTOP_LEVEL_EXCEPTION_FILTER RealFilter;
280     LONG RetValue;
281 
282     /* Debugger and hard error parameters */
283     HANDLE DebugPort = NULL;
284     ULONG_PTR ErrorParameters[4];
285     ULONG DebugResponse, ErrorResponse;
286 
287     /* Post-Mortem "Auto-Execute" (AE) Debugger registry data */
288     HANDLE KeyHandle;
289     OBJECT_ATTRIBUTES ObjectAttributes;
290     UNICODE_STRING ValueString;
291     ULONG Length;
292     UCHAR Buffer[sizeof(KEY_VALUE_PARTIAL_INFORMATION) + MAX_PATH * sizeof(WCHAR)];
293     PKEY_VALUE_PARTIAL_INFORMATION PartialInfo = (PVOID)Buffer;
294     BOOLEAN AeDebugAuto = FALSE;
295     PWCHAR AeDebugPath = NULL;
296     WCHAR AeDebugCmdLine[MAX_PATH];
297 
298     /* Debugger process data */
299     BOOL Success;
300     HRESULT hr;
301     ULONG PrependLength;
302     HANDLE hDebugEvent;
303     HANDLE WaitHandles[2];
304     STARTUPINFOW StartupInfo;
305     PROCESS_INFORMATION ProcessInfo;
306 
307     /* In case this is a nested exception, just kill the process */
308     if (ExceptionRecord->ExceptionFlags & EXCEPTION_NESTED_CALL)
309     {
310         NtTerminateProcess(NtCurrentProcess(), ExceptionRecord->ExceptionCode);
311         return EXCEPTION_EXECUTE_HANDLER;
312     }
313 
314     if ((ExceptionRecord->ExceptionCode == STATUS_ACCESS_VIOLATION) &&
315         (ExceptionRecord->NumberParameters >= 2))
316     {
317         switch (ExceptionRecord->ExceptionInformation[0])
318         {
319             case EXCEPTION_WRITE_FAULT:
320             {
321                 /*
322                  * Change the protection on some write attempts,
323                  * some InstallShield setups have this bug.
324                  */
325                 RetValue = BasepCheckForReadOnlyResource(
326                     (PVOID)ExceptionRecord->ExceptionInformation[1]);
327                 if (RetValue == EXCEPTION_CONTINUE_EXECUTION)
328                     return EXCEPTION_CONTINUE_EXECUTION;
329                 break;
330             }
331 
332             case EXCEPTION_EXECUTE_FAULT:
333                 /* FIXME */
334                 break;
335         }
336     }
337 
338     /* If the process is being debugged, pass the exception to the debugger */
339     Status = NtQueryInformationProcess(NtCurrentProcess(),
340                                        ProcessDebugPort,
341                                        &DebugPort,
342                                        sizeof(DebugPort),
343                                        NULL);
344     if (NT_SUCCESS(Status) && DebugPort)
345     {
346         DPRINT("Passing exception to debugger\n");
347         return EXCEPTION_CONTINUE_SEARCH;
348     }
349 
350     /* No debugger present, let's continue... */
351 
352     RealFilter = RtlDecodePointer(GlobalTopLevelExceptionFilter);
353     if (RealFilter)
354     {
355         RetValue = RealFilter(ExceptionInfo);
356         if (RetValue != EXCEPTION_CONTINUE_SEARCH)
357             return RetValue;
358     }
359 
360     /* ReactOS-specific: DPRINT a stack trace */
361     PrintStackTrace(ExceptionInfo);
362 
363     /*
364      * Now pop up an error if needed. Check both the process-wide (Win32)
365      * and per-thread error-mode flags (NT).
366      */
367     if ((GetErrorMode() & SEM_NOGPFAULTERRORBOX) ||
368         (RtlGetThreadErrorMode() & RTL_SEM_NOGPFAULTERRORBOX))
369     {
370         /* Do not display the pop-up error box, just transfer control to the exception handler */
371         return EXCEPTION_EXECUTE_HANDLER;
372     }
373 
374     /* Save exception code and address */
375     ErrorParameters[0] = (ULONG_PTR)ExceptionRecord->ExceptionCode;
376     ErrorParameters[1] = (ULONG_PTR)ExceptionRecord->ExceptionAddress;
377 
378     if (ExceptionRecord->ExceptionCode == STATUS_IN_PAGE_ERROR)
379     {
380         /*
381          * Get the underlying status code that resulted in the exception,
382          * and just forget about the type of operation (read/write).
383          */
384         ErrorParameters[2] = ExceptionRecord->ExceptionInformation[2];
385     }
386     else // if (ExceptionRecord->ExceptionCode == STATUS_ACCESS_VIOLATION) or others...
387     {
388         /* Get the type of operation that caused the access violation */
389         ErrorParameters[2] = ExceptionRecord->ExceptionInformation[0];
390     }
391 
392     /* Save faulting address */
393     ErrorParameters[3] = ExceptionRecord->ExceptionInformation[1];
394 
395     /*
396      * Prepare the hard error dialog: default to only OK
397      * in case we do not have any debugger at our disposal.
398      */
399     DebugResponse = OptionOk;
400     AeDebugAuto = FALSE;
401 
402     /*
403      * Retrieve Post-Mortem Debugger settings from the registry, under:
404      * HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AeDebug
405      * (REGSTR_PATH_AEDEBUG).
406      */
407 
408     InitializeObjectAttributes(&ObjectAttributes,
409                                &AeDebugKey,
410                                OBJ_CASE_INSENSITIVE,
411                                NULL,
412                                NULL);
413     Status = NtOpenKey(&KeyHandle, KEY_QUERY_VALUE, &ObjectAttributes);
414     if (NT_SUCCESS(Status))
415     {
416         /*
417          * Read the 'Auto' REG_SZ value:
418          * "0" (or any other value): Prompt the user for starting the debugger.
419          * "1": Start the debugger without prompting.
420          */
421         RtlInitUnicodeString(&ValueString, REGSTR_VAL_AEDEBUG_AUTO);
422         Status = NtQueryValueKey(KeyHandle,
423                                  &ValueString,
424                                  KeyValuePartialInformation,
425                                  PartialInfo,
426                                  sizeof(Buffer),
427                                  &Length);
428         if (NT_SUCCESS(Status) && (PartialInfo->Type == REG_SZ))
429         {
430             AeDebugAuto = (*(PWCHAR)PartialInfo->Data == L'1');
431         }
432         else
433         {
434             AeDebugAuto = FALSE;
435         }
436 
437         /*
438          * Read and store the 'Debugger' REG_SZ value. Its usual format is:
439          *    C:\dbgtools\ntsd.exe -p %ld -e %ld -g
440          * with the first and second parameters being respectively
441          * the process ID and a notification event handle.
442          */
443         RtlInitUnicodeString(&ValueString, REGSTR_VAL_AEDEBUG_DEBUGGER);
444         Status = NtQueryValueKey(KeyHandle,
445                                  &ValueString,
446                                  KeyValuePartialInformation,
447                                  PartialInfo,
448                                  sizeof(Buffer),
449                                  &Length);
450         if (NT_SUCCESS(Status) && (PartialInfo->Type == REG_SZ))
451         {
452             /* We hope the string is NULL-terminated */
453             AeDebugPath = (PWCHAR)PartialInfo->Data;
454 
455             /* Skip any prepended whitespace */
456             while (  *AeDebugPath &&
457                    ((*AeDebugPath == L' ') ||
458                     (*AeDebugPath == L'\t')) ) // iswspace(*AeDebugPath)
459             {
460                 ++AeDebugPath;
461             }
462 
463             if (*AeDebugPath)
464             {
465                 /* We have a debugger path, we can prompt the user to debug the program */
466                 DebugResponse = OptionOkCancel;
467             }
468             else
469             {
470                 /* We actually do not have anything, reset the pointer */
471                 AeDebugPath = NULL;
472             }
473         }
474         else
475         {
476             AeDebugPath = NULL;
477         }
478 
479         NtClose(KeyHandle);
480     }
481 
482     // TODO: Start a ReactOS Fault Reporter (unimplemented!)
483     //
484     // For now we are doing the "old way" (aka Win2k), that is also the fallback
485     // case for Windows XP/2003 in case it does not find faultrep.dll to display
486     // the nice "Application Error" dialog box: We use a hard error to communicate
487     // the problem and prompt the user to continue debugging the application or
488     // to terminate it.
489     //
490     // Since Windows XP/2003, we have the ReportFault API available.
491     // See http://www.clausbrod.de/twiki/pub/Blog/DefinePrivatePublic20070616/reportfault.cpp
492     // and https://msdn.microsoft.com/en-us/library/windows/desktop/bb513616(v=vs.85).aspx
493     // and the legacy ReportFault API: https://msdn.microsoft.com/en-us/library/windows/desktop/bb513615(v=vs.85).aspx
494     //
495     // NOTE: Starting Vista+, the fault API is constituted of the WerXXX functions.
496     //
497     // Also see Vostokov's book "Memory Dump Analysis Anthology Collector's Edition, Volume 1"
498     // at: https://books.google.fr/books?id=9w2x6NHljg4C&pg=PA115&lpg=PA115
499 
500     if (!(AeDebugPath && AeDebugAuto))
501     {
502         /*
503          * Either there is no debugger specified, or the debugger should
504          * not start automatically: display the hard error no matter what.
505          * For a first chance exception, allow continuing or debugging;
506          * for a second chance exception, just debug or kill the process.
507          */
508         Status = NtRaiseHardError(STATUS_UNHANDLED_EXCEPTION | HARDERROR_OVERRIDE_ERRORMODE,
509                                   4,
510                                   0,
511                                   ErrorParameters,
512                                   (!IsSecondChance ? DebugResponse : OptionOk),
513                                   &ErrorResponse);
514     }
515     else
516     {
517         Status = STATUS_SUCCESS;
518         ErrorResponse = (AeDebugPath ? ResponseCancel : ResponseOk);
519     }
520 
521     /*
522      * If the user has chosen not to debug the process, or
523      * if this is a second chance exception, kill the process.
524      */
525     if (!NT_SUCCESS(Status) || (ErrorResponse != ResponseCancel) || IsSecondChance)
526         goto Quit;
527 
528     /* If the exception comes from a CSR Server, kill it (this will lead to ReactOS shutdown) */
529     if (BaseRunningInServerProcess)
530     {
531         IsSecondChance = TRUE;
532         goto Quit;
533     }
534 
535     /*
536      * Attach a debugger to this process. The debugger process is given
537      * the process ID of the current process to be debugged, as well as
538      * a notification event handle. After being spawned, the debugger
539      * initializes and attaches to the process by calling DebugActiveProcess.
540      * When the debugger is ready, it signals the notification event,
541      * so that we can give it control over the process being debugged,
542      * by passing it the exception.
543      *
544      * See https://msdn.microsoft.com/en-us/library/ms809754.aspx
545      * and http://www.debuginfo.com/articles/ntsdwatson.html
546      * and https://sourceware.org/ml/gdb-patches/2012-08/msg00893.html
547      * for more details.
548      */
549 
550     /* Create an inheritable notification debug event for the debugger */
551     InitializeObjectAttributes(&ObjectAttributes,
552                                NULL,
553                                OBJ_INHERIT,
554                                NULL,
555                                NULL);
556     Status = NtCreateEvent(&hDebugEvent,
557                            EVENT_ALL_ACCESS,
558                            &ObjectAttributes,
559                            NotificationEvent,
560                            FALSE);
561     if (!NT_SUCCESS(Status))
562         hDebugEvent = NULL;
563 
564     /* Build the debugger command line */
565 
566     Success = FALSE;
567 
568     /*
569      * We will add two longs (process ID and event handle) to the command
570      * line. The biggest 32-bit unsigned int (0xFFFFFFFF == 4.294.967.295)
571      * takes 10 decimal digits. We then count the terminating NULL.
572      */
573     Length = (ULONG)wcslen(AeDebugPath) + 2*10 + 1;
574 
575     /* Check whether the debugger path may be a relative path */
576     if ((*AeDebugPath != L'"') &&
577         (RtlDetermineDosPathNameType_U(AeDebugPath) == RtlPathTypeRelative))
578     {
579         /* Relative path, prepend SystemRoot\System32 */
580         PrependLength = (ULONG)wcslen(SharedUserData->NtSystemRoot) + 10 /* == wcslen(L"\\System32\\") */;
581         if (PrependLength + Length <= ARRAYSIZE(AeDebugCmdLine))
582         {
583             hr = StringCchPrintfW(AeDebugCmdLine,
584                                   PrependLength + 1,
585                                   L"%s\\System32\\",
586                                   SharedUserData->NtSystemRoot);
587             Success = SUCCEEDED(hr);
588         }
589     }
590     else
591     {
592         /* Full path */
593         PrependLength = 0;
594         if (Length <= ARRAYSIZE(AeDebugCmdLine))
595             Success = TRUE;
596     }
597 
598     /* Format the command line */
599     if (Success)
600     {
601         hr = StringCchPrintfW(&AeDebugCmdLine[PrependLength],
602                               Length,
603                               AeDebugPath,
604                               HandleToUlong(NtCurrentTeb()->ClientId.UniqueProcess), // GetCurrentProcessId()
605                               hDebugEvent);
606         Success = SUCCEEDED(hr);
607     }
608 
609     /* Start the debugger */
610     if (Success)
611     {
612         DPRINT1("\nStarting debugger: '%S'\n", AeDebugCmdLine);
613 
614         RtlZeroMemory(&StartupInfo, sizeof(StartupInfo));
615         RtlZeroMemory(&ProcessInfo, sizeof(ProcessInfo));
616 
617         StartupInfo.cb = sizeof(StartupInfo);
618         StartupInfo.lpDesktop = L"WinSta0\\Default";
619 
620         Success = CreateProcessW(NULL,
621                                  AeDebugCmdLine,
622                                  NULL, NULL,
623                                  TRUE, 0,
624                                  NULL, NULL,
625                                  &StartupInfo, &ProcessInfo);
626     }
627 
628     if (Success)
629     {
630         WaitHandles[0] = hDebugEvent;
631         WaitHandles[1] = ProcessInfo.hProcess;
632 
633         /* Loop until the debugger gets ready or terminates unexpectedly */
634         do
635         {
636             /* Alertable wait */
637             Status = NtWaitForMultipleObjects(ARRAYSIZE(WaitHandles),
638                                               WaitHandles,
639                                               WaitAny,
640                                               TRUE, NULL);
641         } while ((Status == STATUS_ALERTED) || (Status == STATUS_USER_APC));
642 
643         /*
644          * The debugger terminated unexpectedly and we cannot attach to it.
645          * Kill the process being debugged.
646          */
647         if (Status == STATUS_WAIT_1)
648         {
649             /* Be sure there is no other debugger attached */
650             Status = NtQueryInformationProcess(NtCurrentProcess(),
651                                                ProcessDebugPort,
652                                                &DebugPort,
653                                                sizeof(DebugPort),
654                                                NULL);
655             if (!NT_SUCCESS(Status) || !DebugPort)
656             {
657                 /* No debugger is attached, kill the process at next round */
658                 IsSecondChance = TRUE;
659             }
660         }
661 
662         CloseHandle(ProcessInfo.hThread);
663         CloseHandle(ProcessInfo.hProcess);
664 
665         if (hDebugEvent)
666             NtClose(hDebugEvent);
667 
668         return EXCEPTION_CONTINUE_SEARCH;
669     }
670 
671     /* We failed starting the debugger, close the event handle and kill the process */
672 
673     if (hDebugEvent)
674         NtClose(hDebugEvent);
675 
676     IsSecondChance = TRUE;
677 
678 
679 Quit:
680     /* If this is a second chance exception, kill the process */
681     if (IsSecondChance)
682         NtTerminateProcess(NtCurrentProcess(), ExceptionRecord->ExceptionCode);
683 
684     /* Otherwise allow handling exceptions in first chance */
685 
686     /*
687      * Returning EXCEPTION_EXECUTE_HANDLER means that the code in
688      * the __except block will be executed. Normally this will end up in a
689      * Terminate process.
690      */
691 
692     return EXCEPTION_EXECUTE_HANDLER;
693 }
694 
695 /*
696  * @implemented
697  */
698 VOID
699 WINAPI
RaiseException(_In_ DWORD dwExceptionCode,_In_ DWORD dwExceptionFlags,_In_ DWORD nNumberOfArguments,_In_opt_ const ULONG_PTR * lpArguments)700 RaiseException(
701     _In_ DWORD dwExceptionCode,
702     _In_ DWORD dwExceptionFlags,
703     _In_ DWORD nNumberOfArguments,
704     _In_opt_ const ULONG_PTR *lpArguments)
705 {
706     EXCEPTION_RECORD ExceptionRecord;
707 
708     /* Setup the exception record */
709     RtlZeroMemory(&ExceptionRecord, sizeof(ExceptionRecord));
710     ExceptionRecord.ExceptionCode = dwExceptionCode;
711     ExceptionRecord.ExceptionRecord = NULL;
712     ExceptionRecord.ExceptionAddress = (PVOID)RaiseException;
713     ExceptionRecord.ExceptionFlags = dwExceptionFlags & EXCEPTION_NONCONTINUABLE;
714 
715     /* Check if we have arguments */
716     if (!lpArguments)
717     {
718         /* We don't */
719         ExceptionRecord.NumberParameters = 0;
720     }
721     else
722     {
723         /* We do, normalize the count */
724         if (nNumberOfArguments > EXCEPTION_MAXIMUM_PARAMETERS)
725             nNumberOfArguments = EXCEPTION_MAXIMUM_PARAMETERS;
726 
727         /* Set the count of parameters and copy them */
728         ExceptionRecord.NumberParameters = nNumberOfArguments;
729         RtlCopyMemory(ExceptionRecord.ExceptionInformation,
730                       lpArguments,
731                       nNumberOfArguments * sizeof(ULONG_PTR));
732     }
733 
734     /* Better handling of Delphi Exceptions... a ReactOS Hack */
735     if (dwExceptionCode == 0xeedface || dwExceptionCode == 0xeedfade)
736     {
737         DPRINT1("Delphi Exception at address: %p\n", ExceptionRecord.ExceptionInformation[0]);
738         DPRINT1("Exception-Object: %p\n", ExceptionRecord.ExceptionInformation[1]);
739         DPRINT1("Exception text: %lx\n", ExceptionRecord.ExceptionInformation[2]);
740     }
741 
742     /* Raise the exception */
743     RtlRaiseException(&ExceptionRecord);
744 }
745 
746 /*
747  * @implemented
748  */
749 UINT
750 WINAPI
SetErrorMode(IN UINT uMode)751 SetErrorMode(IN UINT uMode)
752 {
753     UINT PrevErrMode, NewMode;
754 
755     /* Get the previous mode */
756     PrevErrMode = GetErrorMode();
757     NewMode = uMode;
758 
759     /* Check if failing critical errors was requested */
760     if (NewMode & SEM_FAILCRITICALERRORS)
761     {
762         /* Mask it out, since the native API works differently */
763         NewMode &= ~SEM_FAILCRITICALERRORS;
764     }
765     else
766     {
767         /* OR it if the caller didn't, due to different native semantics */
768         NewMode |= SEM_FAILCRITICALERRORS;
769     }
770 
771     /* Always keep no alignment faults if they were set */
772     NewMode |= (PrevErrMode & SEM_NOALIGNMENTFAULTEXCEPT);
773 
774     /* Set the new mode */
775     NtSetInformationProcess(NtCurrentProcess(),
776                             ProcessDefaultHardErrorMode,
777                             (PVOID)&NewMode,
778                             sizeof(NewMode));
779 
780     /* Return the previous mode */
781     return PrevErrMode;
782 }
783 
784 /*
785  * @implemented
786  */
787 LPTOP_LEVEL_EXCEPTION_FILTER
788 WINAPI
789 DECLSPEC_HOTPATCH
SetUnhandledExceptionFilter(IN LPTOP_LEVEL_EXCEPTION_FILTER lpTopLevelExceptionFilter)790 SetUnhandledExceptionFilter(IN LPTOP_LEVEL_EXCEPTION_FILTER lpTopLevelExceptionFilter)
791 {
792     PVOID EncodedPointer, EncodedOldPointer;
793 
794     EncodedPointer = RtlEncodePointer(lpTopLevelExceptionFilter);
795     EncodedOldPointer = InterlockedExchangePointer((PVOID*)&GlobalTopLevelExceptionFilter,
796                                             EncodedPointer);
797     return RtlDecodePointer(EncodedOldPointer);
798 }
799 
800 /*
801  * @implemented
802  */
803 BOOL
804 WINAPI
IsBadReadPtr(IN LPCVOID lp,IN UINT_PTR ucb)805 IsBadReadPtr(IN LPCVOID lp,
806              IN UINT_PTR ucb)
807 {
808     ULONG PageSize;
809     BOOLEAN Result = FALSE;
810     volatile CHAR *Current;
811     PCHAR Last;
812 
813     /* Quick cases */
814     if (!ucb) return FALSE;
815     if (!lp) return TRUE;
816 
817     /* Get the page size */
818     PageSize = BaseStaticServerData->SysInfo.PageSize;
819 
820     /* Calculate start and end */
821     Current = (volatile CHAR*)lp;
822     Last = (PCHAR)((ULONG_PTR)lp + ucb - 1);
823 
824     /* Another quick failure case */
825     if (Last < Current) return TRUE;
826 
827     /* Enter SEH */
828     _SEH2_TRY
829     {
830         /* Do an initial probe */
831         *Current;
832 
833         /* Align the addresses */
834         Current = (volatile CHAR *)ALIGN_DOWN_POINTER_BY(Current, PageSize);
835         Last = (PCHAR)ALIGN_DOWN_POINTER_BY(Last, PageSize);
836 
837         /* Probe the entire range */
838         while (Current != Last)
839         {
840             Current += PageSize;
841             *Current;
842         }
843     }
844     _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
845     {
846         /* We hit an exception, so return true */
847         Result = TRUE;
848     }
849     _SEH2_END
850 
851     /* Return exception status */
852     return Result;
853 }
854 
855 /*
856  * @implemented
857  */
858 BOOL
859 NTAPI
IsBadHugeReadPtr(LPCVOID lp,UINT_PTR ucb)860 IsBadHugeReadPtr(LPCVOID lp,
861                  UINT_PTR ucb)
862 {
863     /* Implementation is the same on 32-bit */
864     return IsBadReadPtr(lp, ucb);
865 }
866 
867 /*
868  * @implemented
869  */
870 BOOL
871 NTAPI
IsBadCodePtr(FARPROC lpfn)872 IsBadCodePtr(FARPROC lpfn)
873 {
874     /* Executing has the same privileges as reading */
875     return IsBadReadPtr((LPVOID)lpfn, 1);
876 }
877 
878 /*
879  * @implemented
880  */
881 BOOL
882 NTAPI
IsBadWritePtr(IN LPVOID lp,IN UINT_PTR ucb)883 IsBadWritePtr(IN LPVOID lp,
884               IN UINT_PTR ucb)
885 {
886     ULONG PageSize;
887     BOOLEAN Result = FALSE;
888     volatile CHAR *Current;
889     PCHAR Last;
890 
891     /* Quick cases */
892     if (!ucb) return FALSE;
893     if (!lp) return TRUE;
894 
895     /* Get the page size */
896     PageSize = BaseStaticServerData->SysInfo.PageSize;
897 
898     /* Calculate start and end */
899     Current = (volatile CHAR*)lp;
900     Last = (PCHAR)((ULONG_PTR)lp + ucb - 1);
901 
902     /* Another quick failure case */
903     if (Last < Current) return TRUE;
904 
905     /* Enter SEH */
906     _SEH2_TRY
907     {
908         /* Do an initial probe */
909         *Current = *Current;
910 
911         /* Align the addresses */
912         Current = (volatile CHAR *)ALIGN_DOWN_POINTER_BY(Current, PageSize);
913         Last = (PCHAR)ALIGN_DOWN_POINTER_BY(Last, PageSize);
914 
915         /* Probe the entire range */
916         while (Current != Last)
917         {
918             Current += PageSize;
919             *Current = *Current;
920         }
921     }
922     _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
923     {
924         /* We hit an exception, so return true */
925         Result = TRUE;
926     }
927     _SEH2_END
928 
929     /* Return exception status */
930     return Result;
931 }
932 
933 /*
934  * @implemented
935  */
936 BOOL
937 NTAPI
IsBadHugeWritePtr(IN LPVOID lp,IN UINT_PTR ucb)938 IsBadHugeWritePtr(IN LPVOID lp,
939                   IN UINT_PTR ucb)
940 {
941     /* Implementation is the same on 32-bit */
942     return IsBadWritePtr(lp, ucb);
943 }
944 
945 /*
946  * @implemented
947  */
948 BOOL
949 NTAPI
IsBadStringPtrW(IN LPCWSTR lpsz,IN UINT_PTR ucchMax)950 IsBadStringPtrW(IN LPCWSTR lpsz,
951                 IN UINT_PTR ucchMax)
952 {
953     BOOLEAN Result = FALSE;
954     volatile WCHAR *Current;
955     PWCHAR Last;
956     WCHAR Char;
957 
958     /* Quick cases */
959     if (!ucchMax) return FALSE;
960     if (!lpsz) return TRUE;
961 
962     /* Calculate start and end */
963     Current = (volatile WCHAR*)lpsz;
964     Last = (PWCHAR)((ULONG_PTR)lpsz + (ucchMax * 2) - 2);
965 
966     /* Enter SEH */
967     _SEH2_TRY
968     {
969         /* Probe the entire range */
970         Char = *Current++;
971         while ((Char) && (Current != Last)) Char = *Current++;
972     }
973     _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
974     {
975         /* We hit an exception, so return true */
976         Result = TRUE;
977     }
978     _SEH2_END
979 
980     /* Return exception status */
981     return Result;
982 }
983 
984 /*
985  * @implemented
986  */
987 BOOL
988 NTAPI
IsBadStringPtrA(IN LPCSTR lpsz,IN UINT_PTR ucchMax)989 IsBadStringPtrA(IN LPCSTR lpsz,
990                 IN UINT_PTR ucchMax)
991 {
992     BOOLEAN Result = FALSE;
993     volatile CHAR *Current;
994     PCHAR Last;
995     CHAR Char;
996 
997     /* Quick cases */
998     if (!ucchMax) return FALSE;
999     if (!lpsz) return TRUE;
1000 
1001     /* Calculate start and end */
1002     Current = (volatile CHAR*)lpsz;
1003     Last = (PCHAR)((ULONG_PTR)lpsz + ucchMax - 1);
1004 
1005     /* Enter SEH */
1006     _SEH2_TRY
1007     {
1008         /* Probe the entire range */
1009         Char = *Current++;
1010         while ((Char) && (Current != Last)) Char = *Current++;
1011     }
1012     _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
1013     {
1014         /* We hit an exception, so return true */
1015         Result = TRUE;
1016     }
1017     _SEH2_END
1018 
1019     /* Return exception status */
1020     return Result;
1021 }
1022 
1023 /*
1024  * @implemented
1025  */
1026 VOID
1027 WINAPI
SetLastError(IN DWORD dwErrCode)1028 SetLastError(IN DWORD dwErrCode)
1029 {
1030     /* Break if a debugger requested checking for this error code */
1031     if ((g_dwLastErrorToBreakOn) && (g_dwLastErrorToBreakOn == dwErrCode)) DbgBreakPoint();
1032 
1033     /* Set last error if it's a new error */
1034     if (NtCurrentTeb()->LastErrorValue != dwErrCode) NtCurrentTeb()->LastErrorValue = dwErrCode;
1035 }
1036 
1037 /*
1038  * @implemented
1039  */
1040 DWORD
1041 WINAPI
GetLastError(VOID)1042 GetLastError(VOID)
1043 {
1044     /* Return the current value */
1045     return NtCurrentTeb()->LastErrorValue;
1046 }
1047 
1048 /* EOF */
1049