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- Replaced MmGetPageEntry with MmGetPageProtect/MmSetPageProtect in KdbOverwriteInst.

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svn path=/trunk/; revision=10484
This commit is contained in:
Hartmut Birr 2004-08-10 19:49:25 +00:00
parent bc751c87d7
commit a91173016c
1 changed files with 20 additions and 30 deletions
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50
reactos/ntoskrnl/dbg/kdb.c
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@ -16,7 +16,7 @@
* along with this program; if not, write to the Free Software * along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/ */
/* $Id: kdb.c,v 1.26 2004/08/10 01:49:36 navaraf Exp $ /* $Id: kdb.c,v 1.27 2004/08/10 19:49:25 hbirr Exp $
* *
* PROJECT: ReactOS kernel * PROJECT: ReactOS kernel
* FILE: ntoskrnl/dbg/kdb.c * FILE: ntoskrnl/dbg/kdb.c
@ -165,7 +165,6 @@ volatile DWORD x_dr0 = 0, x_dr1 = 0, x_dr2 = 0, x_dr3 = 0, x_dr7 = 0;
extern LONG KdbDisassemble(ULONG Address); extern LONG KdbDisassemble(ULONG Address);
extern LONG KdbGetInstLength(ULONG Address); extern LONG KdbGetInstLength(ULONG Address);
extern PULONG MmGetPageEntry(PVOID PAddress, BOOL CreatePde);
/* FUNCTIONS *****************************************************************/ /* FUNCTIONS *****************************************************************/
@ -408,49 +407,40 @@ KdbDecodeAddress(PUCHAR Buffer, PULONG Address)
NTSTATUS STATIC NTSTATUS STATIC
KdbOverwriteInst(ULONG Address, PUCHAR PreviousInst, UCHAR NewInst) KdbOverwriteInst(ULONG Address, PUCHAR PreviousInst, UCHAR NewInst)
{ {
PULONG BreakPtePtr;
ULONG SavedPte;
NTSTATUS Status; NTSTATUS Status;
/* Get the pte for the page containing the address. */ ULONG Protect;
BreakPtePtr = MmGetPageEntry((PVOID)PAGE_ROUND_DOWN(Address), FALSE); /* Get the protection for the address. */
Protect = MmGetPageProtect(PsGetCurrentProcess(), (PVOID)PAGE_ROUND_DOWN(Address));
/* Return if that page isn't present. */ /* Return if that page isn't present. */
if (BreakPtePtr == NULL) if (Protect & PAGE_NOACCESS)
{
return(STATUS_UNSUCCESSFUL);
}
if (!((*BreakPtePtr) & (1 << 0)))
{ {
return(STATUS_MEMORY_NOT_ALLOCATED); return(STATUS_MEMORY_NOT_ALLOCATED);
} }
/* Saved the old pte and enable write permissions. */ if (Protect & (PAGE_READONLY|PAGE_EXECUTE|PAGE_EXECUTE_READ))
SavedPte = *BreakPtePtr; {
(*BreakPtePtr) |= (1 << 1); MmSetPageProtect(PsGetCurrentProcess(), (PVOID)PAGE_ROUND_DOWN(Address),
/* Flush the TLB. */ (Protect & ~(PAGE_READONLY|PAGE_EXECUTE|PAGE_EXECUTE_READ)) | PAGE_READWRITE);
__asm__ __volatile__ ("movl %%cr3, %%eax\n\t" }
"movl %%eax, %%cr3\n\t"
: : : "memory", "eax");
/* Copy the old instruction back to the caller. */ /* Copy the old instruction back to the caller. */
if (PreviousInst != NULL) if (PreviousInst != NULL)
{ {
Status = MmSafeCopyFromUser(PreviousInst, (PUCHAR)Address, 1); Status = MmSafeCopyFromUser(PreviousInst, (PUCHAR)Address, 1);
if (!NT_SUCCESS(Status)) if (!NT_SUCCESS(Status))
{ {
return(Status); if (Protect & (PAGE_READONLY|PAGE_EXECUTE|PAGE_EXECUTE_READ))
} {
MmSetPageProtect(PsGetCurrentProcess(), (PVOID)PAGE_ROUND_DOWN(Address), Protect);
}
return(Status);
}
} }
/* Copy the new instruction in its place. */ /* Copy the new instruction in its place. */
Status = MmSafeCopyToUser((PUCHAR)Address, &NewInst, 1); Status = MmSafeCopyToUser((PUCHAR)Address, &NewInst, 1);
if (!NT_SUCCESS(Status)) if (Protect & (PAGE_READONLY|PAGE_EXECUTE|PAGE_EXECUTE_READ))
{ {
return(Status); MmSetPageProtect(PsGetCurrentProcess(), (PVOID)PAGE_ROUND_DOWN(Address), Protect);
} }
/* Restore the old pte. */ return Status;
*BreakPtePtr = SavedPte;
/* And flush the tlb again. */
__asm__ __volatile__ ("movl %%cr3, %%eax\n\t"
"movl %%eax, %%cr3\n\t"
: : : "memory", "eax");
return(STATUS_SUCCESS);
} }