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[FAST486]

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Don't perform privilege checks while reading the IDT, GDT or TSS.


svn path=/trunk/; revision=67648
This commit is contained in:
Aleksandar Andrejevic 2015-05-11 02:49:25 +00:00
parent ee08940855
commit f1bf14da62
3 changed files with 39 additions and 22 deletions
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39
reactos/lib/fast486/common.c
View file

@ -123,7 +123,7 @@ Fast486ReadMemory(PFAST486_STATE State,
{
/* We can't prefetch without possibly violating page permissions */
State->PrefetchValid = FALSE;
return Fast486ReadLinearMemory(State, LinearAddress, Buffer, Size);
return Fast486ReadLinearMemory(State, LinearAddress, Buffer, Size, TRUE);
}
}
@ -131,7 +131,8 @@ Fast486ReadMemory(PFAST486_STATE State,
if (Fast486ReadLinearMemory(State,
State->PrefetchAddress,
State->PrefetchCache,
FAST486_CACHE_SIZE))
FAST486_CACHE_SIZE,
TRUE))
{
State->PrefetchValid = TRUE;
@ -150,7 +151,7 @@ Fast486ReadMemory(PFAST486_STATE State,
#endif
{
/* Read from the linear address */
return Fast486ReadLinearMemory(State, LinearAddress, Buffer, Size);
return Fast486ReadLinearMemory(State, LinearAddress, Buffer, Size, TRUE);
}
}
@ -236,7 +237,7 @@ Fast486WriteMemory(PFAST486_STATE State,
#endif
/* Write to the linear address */
return Fast486WriteLinearMemory(State, LinearAddress, Buffer, Size);
return Fast486WriteLinearMemory(State, LinearAddress, Buffer, Size, TRUE);
}
static inline BOOLEAN
@ -253,7 +254,8 @@ Fast486GetIntVector(PFAST486_STATE State,
State->Idtr.Address
+ Number * sizeof(*IdtEntry),
IdtEntry,
sizeof(*IdtEntry)))
sizeof(*IdtEntry),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -325,7 +327,8 @@ Fast486InterruptInternal(PFAST486_STATE State,
State->TaskReg.Base,
&Tss,
State->TaskReg.Limit >= sizeof(FAST486_TSS)
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS)))
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -622,7 +625,8 @@ Fast486TaskSwitch(PFAST486_STATE State, FAST486_TASK_SWITCH_TYPE Type, USHORT Se
State->TaskReg.Base,
&OldTss,
State->TaskReg.Limit >= sizeof(FAST486_TSS)
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS)))
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -649,7 +653,8 @@ Fast486TaskSwitch(PFAST486_STATE State, FAST486_TASK_SWITCH_TYPE Type, USHORT Se
if (!Fast486ReadLinearMemory(State,
State->Gdtr.Address + GET_SEGMENT_INDEX(Selector),
&NewTssDescriptor,
sizeof(NewTssDescriptor)))
sizeof(NewTssDescriptor),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -703,7 +708,8 @@ Fast486TaskSwitch(PFAST486_STATE State, FAST486_TASK_SWITCH_TYPE Type, USHORT Se
NewTssAddress,
&NewTss,
NewTssLimit >= sizeof(FAST486_TSS)
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS)))
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -718,7 +724,8 @@ Fast486TaskSwitch(PFAST486_STATE State, FAST486_TASK_SWITCH_TYPE Type, USHORT Se
State->Gdtr.Address
+ GET_SEGMENT_INDEX(State->TaskReg.Selector),
&OldTssDescriptor,
sizeof(OldTssDescriptor)))
sizeof(OldTssDescriptor),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -730,7 +737,8 @@ Fast486TaskSwitch(PFAST486_STATE State, FAST486_TASK_SWITCH_TYPE Type, USHORT Se
State->Gdtr.Address
+ GET_SEGMENT_INDEX(State->TaskReg.Selector),
&OldTssDescriptor,
sizeof(OldTssDescriptor)))
sizeof(OldTssDescriptor),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -789,7 +797,8 @@ Fast486TaskSwitch(PFAST486_STATE State, FAST486_TASK_SWITCH_TYPE Type, USHORT Se
State->TaskReg.Base,
&OldTss,
State->TaskReg.Limit >= sizeof(FAST486_TSS)
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS)))
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -802,7 +811,8 @@ Fast486TaskSwitch(PFAST486_STATE State, FAST486_TASK_SWITCH_TYPE Type, USHORT Se
if (!Fast486WriteLinearMemory(State,
State->Gdtr.Address + GET_SEGMENT_INDEX(Selector),
&NewTssDescriptor,
sizeof(NewTssDescriptor)))
sizeof(NewTssDescriptor),
FALSE))
{
/* Exception occurred */
return FALSE;
@ -1041,7 +1051,8 @@ Fast486CallGate(PFAST486_STATE State,
State->TaskReg.Base,
&Tss,
State->TaskReg.Limit >= sizeof(FAST486_TSS)
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS)))
? sizeof(FAST486_TSS) : sizeof(FAST486_LEGACY_TSS),
FALSE))
{
/* Exception occurred */
return FALSE;

19
reactos/lib/fast486/common.inl
View file

@ -150,7 +150,8 @@ FASTCALL
Fast486ReadLinearMemory(PFAST486_STATE State,
ULONG LinearAddress,
PVOID Buffer,
ULONG Size)
ULONG Size,
BOOLEAN CheckPrivilege)
{
/* Check if paging is enabled */
if (State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PG)
@ -177,7 +178,7 @@ Fast486ReadLinearMemory(PFAST486_STATE State,
PageLength -= PageOffset;
}
if (!TableEntry.Present || (!TableEntry.Usermode && (Cpl > 0)))
if (CheckPrivilege && (!TableEntry.Present || (!TableEntry.Usermode && (Cpl > 0))))
{
State->ControlRegisters[FAST486_REG_CR2] = Page + PageOffset;
@ -219,7 +220,8 @@ FASTCALL
Fast486WriteLinearMemory(PFAST486_STATE State,
ULONG LinearAddress,
PVOID Buffer,
ULONG Size)
ULONG Size,
BOOLEAN CheckPrivilege)
{
/* Check if paging is enabled */
if (State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PG)
@ -246,9 +248,10 @@ Fast486WriteLinearMemory(PFAST486_STATE State,
PageLength -= PageOffset;
}
if ((!TableEntry.Present || (!TableEntry.Usermode && (Cpl > 0)))
if (CheckPrivilege
&& ((!TableEntry.Present || (!TableEntry.Usermode && (Cpl > 0)))
|| ((State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_WP)
&& !TableEntry.Writeable))
&& !TableEntry.Writeable)))
{
State->ControlRegisters[FAST486_REG_CR2] = Page + PageOffset;
@ -503,7 +506,8 @@ Fast486ReadDescriptorEntry(PFAST486_STATE State,
State->Gdtr.Address
+ GET_SEGMENT_INDEX(Selector),
Entry,
sizeof(*Entry)))
sizeof(*Entry),
FALSE))
{
/* Exception occurred */
*EntryValid = FALSE;
@ -524,7 +528,8 @@ Fast486ReadDescriptorEntry(PFAST486_STATE State,
State->Ldtr.Base
+ GET_SEGMENT_INDEX(Selector),
Entry,
sizeof(*Entry)))
sizeof(*Entry),
FALSE))
{
/* Exception occurred */
*EntryValid = FALSE;

3
reactos/lib/fast486/opgroups.c
View file

@ -1979,7 +1979,8 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodeGroup0F00)
Fast486WriteLinearMemory(State,
State->Gdtr.Address + GET_SEGMENT_INDEX(Selector),
&GdtEntry,
sizeof(GdtEntry));
sizeof(GdtEntry),
FALSE /* We already made sure CPL is 0 */);
}
break;