reactos/ntoskrnl/ke/except.c

   1 /*
   2  * PROJECT:         ReactOS Kernel
   3  * LICENSE:         GPL - See COPYING in the top level directory
   4  * FILE:            ntoskrnl/ke/except.c
   5  * PURPOSE:         Platform independent exception handling
   6  * PROGRAMMERS:     Alex Ionescu (alex.ionescu@reactos.org)
   7  */
   8
   9 /* INCLUDES ******************************************************************/
  10
  11 #include <ntoskrnl.h>
  12 #define NDEBUG
  13 #include <internal/debug.h>
  14
  15 /* FUNCTIONS *****************************************************************/
  16
  17 VOID
  18 NTAPI
  19 KiContinuePreviousModeUser(IN PCONTEXT Context,
  20                            IN PKEXCEPTION_FRAME ExceptionFrame,
  21                            IN PKTRAP_FRAME TrapFrame)
  22 {
  23     CONTEXT LocalContext;
  24
  25     /* We'll have to make a copy and probe it */
  26     ProbeForRead(Context, sizeof(CONTEXT), sizeof(ULONG));
  27     RtlCopyMemory(&LocalContext, Context, sizeof(CONTEXT));
  28     Context = &LocalContext;
  29
  30     /* Convert the context into Exception/Trap Frames */
  31     KeContextToTrapFrame(&LocalContext,
  32                          ExceptionFrame,
  33                          TrapFrame,
  34                          LocalContext.ContextFlags,
  35                          UserMode);
  36 }
  37
  38 NTSTATUS
  39 NTAPI
  40 KiContinue(IN PCONTEXT Context,
  41            IN PKEXCEPTION_FRAME ExceptionFrame,
  42            IN PKTRAP_FRAME TrapFrame)
  43 {
  44     NTSTATUS Status = STATUS_SUCCESS;
  45     KIRQL OldIrql = APC_LEVEL;
  46     KPROCESSOR_MODE PreviousMode = KeGetPreviousMode();
  47
  48     /* Raise to APC_LEVEL, only if needed */
  49     if (KeGetCurrentIrql() < APC_LEVEL) KeRaiseIrql(APC_LEVEL, &OldIrql);
  50
  51     /* Set up SEH to validate the context */
  52     _SEH_TRY
  53     {
  54         /* Check the previous mode */
  55         if (PreviousMode != KernelMode)
  56         {
  57             /* Validate from user-mode */
  58             KiContinuePreviousModeUser(Context,
  59                                        ExceptionFrame,
  60                                        TrapFrame);
  61         }
  62         else
  63         {
  64             /* Convert the context into Exception/Trap Frames */
  65             KeContextToTrapFrame(Context,
  66                                  ExceptionFrame,
  67                                  TrapFrame,
  68                                  Context->ContextFlags,
  69                                  KernelMode);
  70         }
  71     }
  72     _SEH_HANDLE
  73     {
  74         /* Save the exception code */
  75         Status = _SEH_GetExceptionCode();
  76     }
  77     _SEH_END;
  78
  79     /* Lower the IRQL if needed */
  80     if (OldIrql < APC_LEVEL) KeLowerIrql(OldIrql);
  81
  82     /* Return status */
  83     return Status;
  84 }
  85
  86 NTSTATUS
  87 NTAPI
  88 KiRaiseException(IN PEXCEPTION_RECORD ExceptionRecord,
  89                  IN PCONTEXT Context,
  90                  IN PKEXCEPTION_FRAME ExceptionFrame,
  91                  IN PKTRAP_FRAME TrapFrame,
  92                  IN BOOLEAN SearchFrames)
  93 {
  94     KPROCESSOR_MODE PreviousMode = KeGetPreviousMode();
  95     CONTEXT LocalContext;
  96     EXCEPTION_RECORD LocalExceptionRecord;
  97     ULONG ParameterCount, Size;
  98     NTSTATUS Status = STATUS_SUCCESS;
  99
 100     /* Set up SEH */
 101     _SEH_TRY
 102     {
 103         /* Check the previous mode */
 104         if (PreviousMode != KernelMode)
 105         {
 106 #if 0
 107             /* Probe the context */
 108             ProbeForRead(Context, sizeof(CONTEXT), sizeof(ULONG));
 109
 110             /* Probe the Exception Record */
 111             ProbeForRead(ExceptionRecord,
 112                          FIELD_OFFSET(EXCEPTION_RECORD, NumberParameters) +
 113                          sizeof(ULONG),
 114                          sizeof(ULONG));
 115 #endif
 116             /* Validate the maximum parameters */
 117             if ((ParameterCount = ExceptionRecord->NumberParameters) >
 118                 EXCEPTION_MAXIMUM_PARAMETERS)
 119             {
 120                 /* Too large */
 121                 Status = STATUS_INVALID_PARAMETER;
 122                 _SEH_LEAVE;
 123             }
 124
 125             /* Probe the entire parameters now*/
 126             Size = (sizeof(EXCEPTION_RECORD) -
 127                     ((EXCEPTION_MAXIMUM_PARAMETERS - ParameterCount) * sizeof(ULONG)));
 128             ProbeForRead(ExceptionRecord, Size, sizeof(ULONG));
 129
 130             /* Now make copies in the stack */
 131             RtlCopyMemory(&LocalContext, Context, sizeof(CONTEXT));
 132             RtlCopyMemory(&LocalExceptionRecord, ExceptionRecord, Size);
 133             Context = &LocalContext;
 134             ExceptionRecord = &LocalExceptionRecord;
 135
 136             /* Update the parameter count */
 137             ExceptionRecord->NumberParameters = ParameterCount;
 138         }
 139     }
 140     _SEH_HANDLE
 141     {
 142         /* Get the exception code */
 143         Status = _SEH_GetExceptionCode();
 144     }
 145     _SEH_END;
 146
 147     /* Make sure we didn't crash in SEH */
 148     if (NT_SUCCESS(Status))
 149     {
 150         /* Convert the context record */
 151         KeContextToTrapFrame(Context,
 152                              ExceptionFrame,
 153                              TrapFrame,
 154                              Context->ContextFlags,
 155                              PreviousMode);
 156
 157         /* Dispatch the exception */
 158         KiDispatchException(ExceptionRecord,
 159                             ExceptionFrame,
 160                             TrapFrame,
 161                             PreviousMode,
 162                             SearchFrames);
 163     }
 164
 165     /* Return the status */
 166     return Status;
 167 }
 168
 169 /* EOF */