[ros-diffs] [aandrejevic] 69420: [FAST486] - Don't forget to push the error code when the exception handler is a task gate. - Use SS0/ESP0, SS1/ESP1, or SS2/ESP2 for ring 0/1/2 code task CALLs.

Author: aandrejevic
Date: Wed Sep 30 21:08:31 2015
New Revision: 69420

URL: http://svn.reactos.org/svn/reactos?rev=69420&view=rev
Log:
[FAST486]
- Don't forget to push the error code when the exception handler is a task gate.
- Use SS0/ESP0, SS1/ESP1, or SS2/ESP2 for ring 0/1/2 code task CALLs.


Modified:
    trunk/reactos/lib/fast486/common.c

Modified: trunk/reactos/lib/fast486/common.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/lib/fast486/common.c?rev=6…
==============================================================================
--- trunk/reactos/lib/fast486/common.c	[iso-8859-1] (original)
+++ trunk/reactos/lib/fast486/common.c	[iso-8859-1] Wed Sep 30 21:08:31 2015
@@ -313,7 +313,13 @@
         if (IdtEntry->Type == FAST486_TASK_GATE_SIGNATURE)
         {
             /* Task call */
-            return Fast486TaskSwitch(State, FAST486_TASK_CALL, IdtEntry->Selector);
+            if (!Fast486TaskSwitch(State, FAST486_TASK_CALL, IdtEntry->Selector))
+            {
+                /* Exception occurred */
+                return FALSE;
+            }
+
+            goto Finish;
         }
 
         /* Check if the interrupt handler is more privileged or if we're in V86 mode
*/
@@ -428,7 +434,7 @@
         }
 
         /* Clear NT */
-       State->Flags.Nt = FALSE;
+        State->Flags.Nt = FALSE;
 
         if (OldVm)
         {
@@ -496,6 +502,8 @@
 
     /* Push the instruction pointer */
     if (!Fast486StackPushInternal(State, GateSize, OldEip)) return FALSE;
+
+Finish:
 
     if (PushErrorCode)
     {
@@ -908,15 +916,45 @@
         State->GeneralRegs[FAST486_REG_ECX].Long = NewTss.Ecx;
         State->GeneralRegs[FAST486_REG_EDX].Long = NewTss.Edx;
         State->GeneralRegs[FAST486_REG_EBX].Long = NewTss.Ebx;
-        State->GeneralRegs[FAST486_REG_ESP].Long = NewTss.Esp;
         State->GeneralRegs[FAST486_REG_EBP].Long = NewTss.Ebp;
         State->GeneralRegs[FAST486_REG_ESI].Long = NewTss.Esi;
         State->GeneralRegs[FAST486_REG_EDI].Long = NewTss.Edi;
         NewEs = NewTss.Es;
         NewCs = NewTss.Cs;
-        NewSs = NewTss.Ss;
         NewDs = NewTss.Ds;
         NewLdtr = NewTss.Ldtr;
+
+        if (Type == FAST486_TASK_CALL && State->Cpl < 3)
+        {
+            switch (State->Cpl)
+            {
+                case 0:
+                {
+                    State->GeneralRegs[FAST486_REG_ESP].Long = NewTss.Esp0;
+                    NewSs = NewTss.Ss0;
+                    break;
+                }
+
+                case 1:
+                {
+                    State->GeneralRegs[FAST486_REG_ESP].Long = NewTss.Esp1;
+                    NewSs = NewTss.Ss1;
+                    break;
+                }
+
+                case 2:
+                {
+                    State->GeneralRegs[FAST486_REG_ESP].Long = NewTss.Esp2;
+                    NewSs = NewTss.Ss2;
+                    break;
+                }
+            }
+        }
+        else
+        {
+            State->GeneralRegs[FAST486_REG_ESP].Long = NewTss.Esp;
+            NewSs = NewTss.Ss;
+        }
     }
     else
     {
@@ -926,15 +964,45 @@
         State->GeneralRegs[FAST486_REG_ECX].LowWord = NewLegacyTss->Cx;
         State->GeneralRegs[FAST486_REG_EDX].LowWord = NewLegacyTss->Dx;
         State->GeneralRegs[FAST486_REG_EBX].LowWord = NewLegacyTss->Bx;
-        State->GeneralRegs[FAST486_REG_ESP].LowWord = NewLegacyTss->Sp;
         State->GeneralRegs[FAST486_REG_EBP].LowWord = NewLegacyTss->Bp;
         State->GeneralRegs[FAST486_REG_ESI].LowWord = NewLegacyTss->Si;
         State->GeneralRegs[FAST486_REG_EDI].LowWord = NewLegacyTss->Di;
         NewEs = NewLegacyTss->Es;
         NewCs = NewLegacyTss->Cs;
-        NewSs = NewLegacyTss->Ss;
         NewDs = NewLegacyTss->Ds;
         NewLdtr = NewLegacyTss->Ldtr;
+
+        if (Type == FAST486_TASK_CALL && State->Cpl < 3)
+        {
+            switch (State->Cpl)
+            {
+                case 0:
+                {
+                    State->GeneralRegs[FAST486_REG_ESP].Long = NewLegacyTss->Sp0;
+                    NewSs = NewLegacyTss->Ss0;
+                    break;
+                }
+
+                case 1:
+                {
+                    State->GeneralRegs[FAST486_REG_ESP].Long = NewLegacyTss->Sp1;
+                    NewSs = NewLegacyTss->Ss1;
+                    break;
+                }
+
+                case 2:
+                {
+                    State->GeneralRegs[FAST486_REG_ESP].Long = NewLegacyTss->Sp2;
+                    NewSs = NewLegacyTss->Ss2;
+                    break;
+                }
+            }
+        }
+        else
+        {
+            State->GeneralRegs[FAST486_REG_ESP].Long = NewLegacyTss->Sp;
+            NewSs = NewLegacyTss->Ss;
+        }
     }
 
     /* Set the NT flag if nesting */