dlls/ntdll/exception.c

   1 /*
   2  * NT exception handling routines
   3  *
   4  * Copyright 1999 Turchanov Sergey
   5  * Copyright 1999 Alexandre Julliard
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include "config.h"
  23 #include "wine/port.h"
  24
  25 #include <assert.h>
  26 #include <signal.h>
  27 #include <stdarg.h>
  28
  29 #include "ntstatus.h"
  30 #include "windef.h"
  31 #include "winbase.h"
  32 #include "thread.h"
  33 #include "winternl.h"
  34 #include "wine/exception.h"
  35 #include "wine/server.h"
  36 #include "wine/list.h"
  37 #include "wine/debug.h"
  38 #include "excpt.h"
  39 #include "ntdll_misc.h"
  40
  41 WINE_DEFAULT_DEBUG_CHANNEL(seh);
  42
  43 /* Exception record for handling exceptions happening inside exception handlers */
  44 typedef struct
  45 {
  46     EXCEPTION_REGISTRATION_RECORD frame;
  47     EXCEPTION_REGISTRATION_RECORD *prevFrame;
  48 } EXC_NESTED_FRAME;
  49
  50 typedef struct
  51 {
  52     struct list                 entry;
  53     PVECTORED_EXCEPTION_HANDLER func;
  54 } VECTORED_HANDLER;
  55
  56 static struct list vectored_handlers = LIST_INIT(vectored_handlers);
  57
  58 static CRITICAL_SECTION vectored_handlers_section;
  59 static CRITICAL_SECTION_DEBUG critsect_debug =
  60 {
  61     0, 0, &vectored_handlers_section,
  62     { &critsect_debug.ProcessLocksList, &critsect_debug.ProcessLocksList },
  63       0, 0, { 0, (DWORD)(__FILE__ ": vectored_handlers_section") }
  64 };
  65 static CRITICAL_SECTION vectored_handlers_section = { &critsect_debug, -1, 0, 0, 0, 0 };
  66
  67 #ifdef __i386__
  68 # define GET_IP(context) ((LPVOID)(context)->Eip)
  69 #elif defined(__sparc__)
  70 # define GET_IP(context) ((LPVOID)(context)->pc)
  71 #elif defined(__powerpc__)
  72 # define GET_IP(context) ((LPVOID)(context)->Iar)
  73 #else
  74 # error You must define GET_IP for this CPU
  75 #endif
  76
  77
  78 /*******************************************************************
  79  *         EXC_RaiseHandler
  80  *
  81  * Handler for exceptions happening inside a handler.
  82  */
  83 static DWORD EXC_RaiseHandler( EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RECORD *frame,
  84                                CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher )
  85 {
  86     if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
  87         return ExceptionContinueSearch;
  88     /* We shouldn't get here so we store faulty frame in dispatcher */
  89     *dispatcher = ((EXC_NESTED_FRAME*)frame)->prevFrame;
  90     return ExceptionNestedException;
  91 }
  92
  93
  94 /*******************************************************************
  95  *         EXC_UnwindHandler
  96  *
  97  * Handler for exceptions happening inside an unwind handler.
  98  */
  99 static DWORD EXC_UnwindHandler( EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RECORD *frame,
 100                                 CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher )
 101 {
 102     if (!(rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND)))
 103         return ExceptionContinueSearch;
 104     /* We shouldn't get here so we store faulty frame in dispatcher */
 105     *dispatcher = ((EXC_NESTED_FRAME*)frame)->prevFrame;
 106     return ExceptionCollidedUnwind;
 107 }
 108
 109
 110 /*******************************************************************
 111  *         EXC_CallHandler
 112  *
 113  * Call an exception handler, setting up an exception frame to catch exceptions
 114  * happening during the handler execution.
 115  * Please do not change the first 4 parameters order in any way - some exceptions handlers
 116  * rely on Base Pointer (EBP) to have a fixed position related to the exception frame
 117  */
 118 static DWORD EXC_CallHandler( EXCEPTION_RECORD *record, EXCEPTION_REGISTRATION_RECORD *frame,
 119                               CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher,
 120                               PEXCEPTION_HANDLER handler, PEXCEPTION_HANDLER nested_handler)
 121 {
 122     EXC_NESTED_FRAME newframe;
 123     DWORD ret;
 124
 125     newframe.frame.Handler = nested_handler;
 126     newframe.prevFrame     = frame;
 127     __wine_push_frame( &newframe.frame );
 128     TRACE( "calling handler at %p code=%lx flags=%lx\n",
 129            handler, record->ExceptionCode, record->ExceptionFlags );
 130     ret = handler( record, frame, context, dispatcher );
 131     TRACE( "handler returned %lx\n", ret );
 132     __wine_pop_frame( &newframe.frame );
 133     return ret;
 134 }
 135
 136
 137 /**********************************************************************
 138  *           send_debug_event
 139  *
 140  * Send an EXCEPTION_DEBUG_EVENT event to the debugger.
 141  */
 142 static int send_debug_event( EXCEPTION_RECORD *rec, int first_chance, CONTEXT *context )
 143 {
 144     int ret;
 145     HANDLE handle = 0;
 146
 147     if (!NtCurrentTeb()->Peb->BeingDebugged) return 0;  /* no debugger present */
 148
 149     SERVER_START_REQ( queue_exception_event )
 150     {
 151         req->first   = first_chance;
 152         wine_server_add_data( req, context, sizeof(*context) );
 153         wine_server_add_data( req, rec, sizeof(*rec) );
 154         if (!wine_server_call( req )) handle = reply->handle;
 155     }
 156     SERVER_END_REQ;
 157     if (!handle) return 0;
 158
 159     /* No need to wait on the handle since the process gets suspended
 160      * once the event is passed to the debugger, so when we get back
 161      * here the event has been continued already.
 162      */
 163     SERVER_START_REQ( get_exception_status )
 164     {
 165         req->handle = handle;
 166         wine_server_set_reply( req, context, sizeof(*context) );
 167         wine_server_call( req );
 168         ret = reply->status;
 169     }
 170     SERVER_END_REQ;
 171     NtClose( handle );
 172     return ret;
 173 }
 174
 175
 176 /**********************************************************************
 177  *           call_vectored_handlers
 178  *
 179  * Call the vectored handlers chain.
 180  */
 181 static LONG call_vectored_handlers( EXCEPTION_RECORD *rec, CONTEXT *context )
 182 {
 183     struct list *ptr;
 184     LONG ret = EXCEPTION_CONTINUE_SEARCH;
 185     EXCEPTION_POINTERS except_ptrs;
 186
 187     except_ptrs.ExceptionRecord = rec;
 188     except_ptrs.ContextRecord = context;
 189
 190     RtlEnterCriticalSection( &vectored_handlers_section );
 191     LIST_FOR_EACH( ptr, &vectored_handlers )
 192     {
 193         VECTORED_HANDLER *handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 194         ret = handler->func( &except_ptrs );
 195         if (ret == EXCEPTION_CONTINUE_EXECUTION) break;
 196     }
 197     RtlLeaveCriticalSection( &vectored_handlers_section );
 198     return ret;
 199 }
 200
 201
 202 /*******************************************************************
 203  *         EXC_DefaultHandling
 204  *
 205  * Default handling for exceptions. Called when we didn't find a suitable handler.
 206  */
 207 static void EXC_DefaultHandling( EXCEPTION_RECORD *rec, CONTEXT *context )
 208 {
 209     if (send_debug_event( rec, FALSE, context ) == DBG_CONTINUE) return;  /* continue execution */
 210
 211     if (rec->ExceptionFlags & EH_STACK_INVALID)
 212         ERR("Exception frame is not in stack limits => unable to dispatch exception.\n");
 213     else if (rec->ExceptionCode == EXCEPTION_NONCONTINUABLE_EXCEPTION)
 214         ERR("Process attempted to continue execution after noncontinuable exception.\n");
 215     else
 216         ERR("Unhandled exception code %lx flags %lx addr %p\n",
 217             rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
 218     NtTerminateProcess( NtCurrentProcess(), 1 );
 219 }
 220
 221
 222 /***********************************************************************
 223  *              RtlRaiseException (NTDLL.@)
 224  */
 225 void WINAPI EXC_RtlRaiseException( EXCEPTION_RECORD *rec, CONTEXT *context )
 226 {
 227     PEXCEPTION_REGISTRATION_RECORD frame, dispatch, nested_frame;
 228     EXCEPTION_RECORD newrec;
 229     DWORD res, c;
 230
 231     TRACE( "code=%lx flags=%lx addr=%p\n", rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
 232     for (c=0; c<rec->NumberParameters; c++) TRACE(" info[%ld]=%08lx\n", c, rec->ExceptionInformation[c]);
 233     if (rec->ExceptionCode == EXCEPTION_WINE_STUB)
 234         FIXME( "call to unimplemented function %s.%s\n",
 235                (char*)rec->ExceptionInformation[0], (char*)rec->ExceptionInformation[1] );
 236 #ifdef __i386__
 237     else
 238     {
 239         TRACE(" eax=%08lx ebx=%08lx ecx=%08lx edx=%08lx esi=%08lx edi=%08lx\n",
 240               context->Eax, context->Ebx, context->Ecx,
 241               context->Edx, context->Esi, context->Edi );
 242         TRACE(" ebp=%08lx esp=%08lx cs=%04lx ds=%04lx es=%04lx fs=%04lx gs=%04lx flags=%08lx\n",
 243               context->Ebp, context->Esp, context->SegCs, context->SegDs,
 244               context->SegEs, context->SegFs, context->SegGs, context->EFlags );
 245     }
 246 #endif
 247
 248     if (send_debug_event( rec, TRUE, context ) == DBG_CONTINUE) return;  /* continue execution */
 249
 250     if (call_vectored_handlers( rec, context ) == EXCEPTION_CONTINUE_EXECUTION) return;
 251
 252     frame = NtCurrentTeb()->Tib.ExceptionList;
 253     nested_frame = NULL;
 254     while (frame != (PEXCEPTION_REGISTRATION_RECORD)~0UL)
 255     {
 256         /* Check frame address */
 257         if (((void*)frame < NtCurrentTeb()->Tib.StackLimit) ||
 258             ((void*)(frame+1) > NtCurrentTeb()->Tib.StackBase) ||
 259             (int)frame & 3)
 260         {
 261             rec->ExceptionFlags |= EH_STACK_INVALID;
 262             break;
 263         }
 264
 265         /* Call handler */
 266         res = EXC_CallHandler( rec, frame, context, &dispatch, frame->Handler, EXC_RaiseHandler );
 267         if (frame == nested_frame)
 268         {
 269             /* no longer nested */
 270             nested_frame = NULL;
 271             rec->ExceptionFlags &= ~EH_NESTED_CALL;
 272         }
 273
 274         switch(res)
 275         {
 276         case ExceptionContinueExecution:
 277             if (!(rec->ExceptionFlags & EH_NONCONTINUABLE)) return;
 278             newrec.ExceptionCode    = STATUS_NONCONTINUABLE_EXCEPTION;
 279             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 280             newrec.ExceptionRecord  = rec;
 281             newrec.NumberParameters = 0;
 282             RtlRaiseException( &newrec );  /* never returns */
 283             break;
 284         case ExceptionContinueSearch:
 285             break;
 286         case ExceptionNestedException:
 287             if (nested_frame < dispatch) nested_frame = dispatch;
 288             rec->ExceptionFlags |= EH_NESTED_CALL;
 289             break;
 290         default:
 291             newrec.ExceptionCode    = STATUS_INVALID_DISPOSITION;
 292             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 293             newrec.ExceptionRecord  = rec;
 294             newrec.NumberParameters = 0;
 295             RtlRaiseException( &newrec );  /* never returns */
 296             break;
 297         }
 298         frame = frame->Prev;
 299     }
 300     EXC_DefaultHandling( rec, context );
 301 }
 302
 303 #ifdef DEFINE_REGS_ENTRYPOINT
 304 DEFINE_REGS_ENTRYPOINT( RtlRaiseException, EXC_RtlRaiseException, 4, 4 );
 305 #else
 306 void WINAPI RtlRaiseException( EXCEPTION_RECORD *rec )
 307 {
 308     CONTEXT context;
 309     memset( &context, 0, sizeof(context) );
 310     EXC_RtlRaiseException( rec, &context );
 311 }
 312 #endif
 313
 314
 315 /*******************************************************************
 316  *              RtlUnwind (NTDLL.@)
 317  */
 318 void WINAPI EXC_RtlUnwind( PEXCEPTION_REGISTRATION_RECORD pEndFrame, PVOID unusedEip,
 319                            PEXCEPTION_RECORD pRecord, PVOID returnEax, CONTEXT *context )
 320 {
 321     EXCEPTION_RECORD record, newrec;
 322     PEXCEPTION_REGISTRATION_RECORD frame, dispatch;
 323
 324 #ifdef __i386__
 325     context->Eax = (DWORD)returnEax;
 326 #endif
 327
 328     /* build an exception record, if we do not have one */
 329     if (!pRecord)
 330     {
 331         record.ExceptionCode    = STATUS_UNWIND;
 332         record.ExceptionFlags   = 0;
 333         record.ExceptionRecord  = NULL;
 334         record.ExceptionAddress = GET_IP(context);
 335         record.NumberParameters = 0;
 336         pRecord = &record;
 337     }
 338
 339     pRecord->ExceptionFlags |= EH_UNWINDING | (pEndFrame ? 0 : EH_EXIT_UNWIND);
 340
 341     TRACE( "code=%lx flags=%lx\n", pRecord->ExceptionCode, pRecord->ExceptionFlags );
 342
 343     /* get chain of exception frames */
 344     frame = NtCurrentTeb()->Tib.ExceptionList;
 345     while ((frame != (PEXCEPTION_REGISTRATION_RECORD)~0UL) && (frame != pEndFrame))
 346     {
 347         /* Check frame address */
 348         if (pEndFrame && (frame > pEndFrame))
 349         {
 350             newrec.ExceptionCode    = STATUS_INVALID_UNWIND_TARGET;
 351             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 352             newrec.ExceptionRecord  = pRecord;
 353             newrec.NumberParameters = 0;
 354             RtlRaiseException( &newrec );  /* never returns */
 355         }
 356         if (((void*)frame < NtCurrentTeb()->Tib.StackLimit) ||
 357             ((void*)(frame+1) > NtCurrentTeb()->Tib.StackBase) ||
 358             (int)frame & 3)
 359         {
 360             newrec.ExceptionCode    = STATUS_BAD_STACK;
 361             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 362             newrec.ExceptionRecord  = pRecord;
 363             newrec.NumberParameters = 0;
 364             RtlRaiseException( &newrec );  /* never returns */
 365         }
 366
 367         /* Call handler */
 368         switch(EXC_CallHandler( pRecord, frame, context, &dispatch,
 369                                 frame->Handler, EXC_UnwindHandler ))
 370         {
 371         case ExceptionContinueSearch:
 372             break;
 373         case ExceptionCollidedUnwind:
 374             frame = dispatch;
 375             break;
 376         default:
 377             newrec.ExceptionCode    = STATUS_INVALID_DISPOSITION;
 378             newrec.ExceptionFlags   = EH_NONCONTINUABLE;
 379             newrec.ExceptionRecord  = pRecord;
 380             newrec.NumberParameters = 0;
 381             RtlRaiseException( &newrec );  /* never returns */
 382             break;
 383         }
 384         frame = __wine_pop_frame( frame );
 385     }
 386 }
 387
 388 #ifdef DEFINE_REGS_ENTRYPOINT
 389 DEFINE_REGS_ENTRYPOINT( RtlUnwind, EXC_RtlUnwind, 16, 16 );
 390 #else
 391 void WINAPI RtlUnwind( PVOID pEndFrame, PVOID unusedEip,
 392                        PEXCEPTION_RECORD pRecord, PVOID returnEax )
 393 {
 394     CONTEXT context;
 395     memset( &context, 0, sizeof(context) );
 396     EXC_RtlUnwind( pEndFrame, unusedEip, pRecord, returnEax, &context );
 397 }
 398 #endif
 399
 400
 401 /*******************************************************************
 402  *              NtRaiseException (NTDLL.@)
 403  */
 404 void WINAPI EXC_NtRaiseException( EXCEPTION_RECORD *rec, CONTEXT *ctx,
 405                                   BOOL first, CONTEXT *context )
 406 {
 407     EXC_RtlRaiseException( rec, ctx );
 408     *context = *ctx;
 409 }
 410
 411 #ifdef DEFINE_REGS_ENTRYPOINT
 412 DEFINE_REGS_ENTRYPOINT( NtRaiseException, EXC_NtRaiseException, 12, 12 );
 413 #else
 414 void WINAPI NtRaiseException( EXCEPTION_RECORD *rec, CONTEXT *ctx, BOOL first )
 415 {
 416     CONTEXT context;
 417     memset( &context, 0, sizeof(context) );
 418     EXC_NtRaiseException( rec, ctx, first, &context );
 419 }
 420 #endif
 421
 422
 423 /***********************************************************************
 424  *            RtlRaiseStatus  (NTDLL.@)
 425  *
 426  * Raise an exception with ExceptionCode = status
 427  */
 428 void WINAPI RtlRaiseStatus( NTSTATUS status )
 429 {
 430     EXCEPTION_RECORD ExceptionRec;
 431
 432     ExceptionRec.ExceptionCode    = status;
 433     ExceptionRec.ExceptionFlags   = EH_NONCONTINUABLE;
 434     ExceptionRec.ExceptionRecord  = NULL;
 435     ExceptionRec.NumberParameters = 0;
 436     RtlRaiseException( &ExceptionRec );
 437 }
 438
 439
 440 /*******************************************************************
 441  *         RtlAddVectoredExceptionHandler   (NTDLL.@)
 442  */
 443 PVOID WINAPI RtlAddVectoredExceptionHandler( ULONG first, PVECTORED_EXCEPTION_HANDLER func )
 444 {
 445     VECTORED_HANDLER *handler = RtlAllocateHeap( GetProcessHeap(), 0, sizeof(*handler) );
 446     if (handler)
 447     {
 448         handler->func = func;
 449         RtlEnterCriticalSection( &vectored_handlers_section );
 450         if (first) list_add_head( &vectored_handlers, &handler->entry );
 451         else list_add_tail( &vectored_handlers, &handler->entry );
 452         RtlLeaveCriticalSection( &vectored_handlers_section );
 453     }
 454     return handler;
 455 }
 456
 457
 458 /*******************************************************************
 459  *         RtlRemoveVectoredExceptionHandler   (NTDLL.@)
 460  */
 461 ULONG WINAPI RtlRemoveVectoredExceptionHandler( PVOID handler )
 462 {
 463     struct list *ptr;
 464     ULONG ret = FALSE;
 465
 466     RtlEnterCriticalSection( &vectored_handlers_section );
 467     LIST_FOR_EACH( ptr, &vectored_handlers )
 468     {
 469         if (ptr == &((VECTORED_HANDLER *)handler)->entry)
 470         {
 471             list_remove( ptr );
 472             ret = TRUE;
 473             break;
 474         }
 475     }
 476     RtlLeaveCriticalSection( &vectored_handlers_section );
 477     if (ret) RtlFreeHeap( GetProcessHeap(), 0, handler );
 478     return ret;
 479 }
 480
 481
 482 /*************************************************************
 483  *            __wine_exception_handler (NTDLL.@)
 484  *
 485  * Exception handler for exception blocks declared in Wine code.
 486  */
 487 DWORD __wine_exception_handler( EXCEPTION_RECORD *record, EXCEPTION_REGISTRATION_RECORD *frame,
 488                                 CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **pdispatcher )
 489 {
 490     __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
 491
 492     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND | EH_NESTED_CALL))
 493         return ExceptionContinueSearch;
 494     if (wine_frame->u.filter)
 495     {
 496         EXCEPTION_POINTERS ptrs;
 497         ptrs.ExceptionRecord = record;
 498         ptrs.ContextRecord = context;
 499         switch(wine_frame->u.filter( &ptrs ))
 500         {
 501         case EXCEPTION_CONTINUE_SEARCH:
 502             return ExceptionContinueSearch;
 503         case EXCEPTION_CONTINUE_EXECUTION:
 504             return ExceptionContinueExecution;
 505         case EXCEPTION_EXECUTE_HANDLER:
 506             break;
 507         default:
 508             MESSAGE( "Invalid return value from exception filter\n" );
 509             assert( FALSE );
 510         }
 511     }
 512     /* hack to make GetExceptionCode() work in handler */
 513     wine_frame->ExceptionCode   = record->ExceptionCode;
 514     wine_frame->ExceptionRecord = wine_frame;
 515
 516     RtlUnwind( frame, 0, record, 0 );
 517     __wine_pop_frame( frame );
 518     siglongjmp( wine_frame->jmp, 1 );
 519 }
 520
 521
 522 /*************************************************************
 523  *            __wine_finally_handler (NTDLL.@)
 524  *
 525  * Exception handler for try/finally blocks declared in Wine code.
 526  */
 527 DWORD __wine_finally_handler( EXCEPTION_RECORD *record, EXCEPTION_REGISTRATION_RECORD *frame,
 528                               CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **pdispatcher )
 529 {
 530     if (record->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
 531     {
 532         __WINE_FRAME *wine_frame = (__WINE_FRAME *)frame;
 533         wine_frame->u.finally_func( FALSE );
 534     }
 535     return ExceptionContinueSearch;
 536 }