[pschweitzer] 68829: [NTFS] Totally rewrite the way MFT records attributes are handled. Up to now, we were having really similar loops, only looking at the resident part of the attribute list, not ...

Author: pschweitzer
Date: Wed Aug 26 18:20:04 2015
New Revision: 68829

URL: http://svn.reactos.org/svn/reactos?rev=68829&view=rev
Log:
[NTFS]
Totally rewrite the way MFT records attributes are handled.
Up to now, we were having really similar loops, only looking at the resident part of the
attribute list, not really caring about how the loop was going.

This was leading to some issues:
- In case the attribute we were looking for was stored in the non-resident part of the
attribute list, we would miss it (excepted in the case of FindAttribute() which was
properly browsing the whole attribute list).
- In the specific case of FindAttribute(), one would have been able to setup a broken MFT
record with the resident attribute list pointing on the non resident attribute list which
itself would point to the resident attribute list. In such case, the driver would loop
forever caught on the loop, allocating tones of memory. It was possible to trigger this by
user space, from a non-privileged user, just by browsing the right directory entry.
- In the case of the other loops (non FindAttribute()), another issue (other than missing
attributes) was present, one would have been able to setup a broken MFT record with an
attribute of null-length. This would have caused the driver to loop forever on the
attribute list. This could be triggered from usermode too. And could be triggered by a
non-privileged user.

This commit introduces a new set of functions for attributes browsing:
FindFirstAttribute(), FindNextAttribute(), FindCloseAttribute(). It allows safely browsing
attributes and handles broken cases. It also performs reading of the attribute list when
present and makes sure there's only one read. This method should be the only one to
use to browse the attributes.
The whole NTFS code base has been converted to use this newly set of functions. This
really simplifies the implementation of FindAttribute(), and prevent unsafe code
duplication.

CORE-10037 #resolve #comment Fixed with r68829

Modified:
    trunk/reactos/drivers/filesystems/ntfs/attrib.c
    trunk/reactos/drivers/filesystems/ntfs/create.c
    trunk/reactos/drivers/filesystems/ntfs/dirctl.c
    trunk/reactos/drivers/filesystems/ntfs/fcb.c
    trunk/reactos/drivers/filesystems/ntfs/finfo.c
    trunk/reactos/drivers/filesystems/ntfs/fsctl.c
    trunk/reactos/drivers/filesystems/ntfs/mft.c
    trunk/reactos/drivers/filesystems/ntfs/ntfs.h
    trunk/reactos/drivers/filesystems/ntfs/rw.c

Modified: trunk/reactos/drivers/filesystems/ntfs/attrib.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/a…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/attrib.c	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/attrib.c	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -23,6 +23,7 @@
  * PROGRAMMERS:      Eric Kohl
  *                   Valentin Verkhovsky
  *                   Hervé Poussineau (hpoussin(a)reactos.org)
+ *                   Pierre Schweitzer (pierre(a)reactos.org)
  */
 
 /* INCLUDES *****************************************************************/
@@ -92,6 +93,207 @@
     return TRUE;
 }
 
+static
+NTSTATUS
+InternalReadNonResidentAttributes(PFIND_ATTR_CONTXT Context)
+{
+    ULONGLONG ListSize;
+    PNTFS_ATTR_RECORD Attribute;
+    PNTFS_ATTR_CONTEXT ListContext;
+
+    DPRINT("InternalReadNonResidentAttributes(%p)\n", Context);
+
+    Attribute = Context->CurrAttr;
+    ASSERT(Attribute->Type == AttributeAttributeList);
+
+    if (Context->OnlyResident)
+    {
+        Context->NonResidentStart = NULL;
+        Context->NonResidentEnd = NULL;
+        return STATUS_SUCCESS;
+    }
+
+    if (Context->NonResidentStart != NULL)
+    {
+        return STATUS_FILE_CORRUPT_ERROR;
+    }
+
+    ListContext = PrepareAttributeContext(Attribute);
+    ListSize = AttributeDataLength(&ListContext->Record);
+    if (ListSize > 0xFFFFFFFF)
+    {
+        ReleaseAttributeContext(ListContext);
+        return STATUS_BUFFER_OVERFLOW;
+    }
+
+    Context->NonResidentStart = ExAllocatePoolWithTag(NonPagedPool, (ULONG)ListSize,
TAG_NTFS);
+    if (Context->NonResidentStart == NULL)
+    {
+        ReleaseAttributeContext(ListContext);
+        return STATUS_INSUFFICIENT_RESOURCES;
+    }
+
+    if (ReadAttribute(Context->Vcb, ListContext, 0,
(PCHAR)Context->NonResidentStart, (ULONG)ListSize) != ListSize)
+    {
+        ExFreePoolWithTag(Context->NonResidentStart, TAG_NTFS);
+        Context->NonResidentStart = NULL;
+        ReleaseAttributeContext(ListContext);
+        return STATUS_FILE_CORRUPT_ERROR;
+    }
+
+    ReleaseAttributeContext(ListContext);
+    Context->NonResidentEnd = (PNTFS_ATTR_RECORD)((PCHAR)Context->NonResidentStart
+ ListSize);
+    return STATUS_SUCCESS;
+}
+
+static
+PNTFS_ATTR_RECORD
+InternalGetNextAttribute(PFIND_ATTR_CONTXT Context)
+{
+    if (Context->CurrAttr == (PVOID)-1)
+    {
+        return NULL;
+    }
+
+    if (Context->CurrAttr >= Context->FirstAttr &&
+        Context->CurrAttr < Context->LastAttr)
+    {
+        if (Context->CurrAttr->Length == 0)
+        {
+            DPRINT1("Broken length!\n");
+            Context->CurrAttr = (PVOID)-1;
+            return NULL;
+        }
+
+        Context->CurrAttr = (PNTFS_ATTR_RECORD)((ULONG_PTR)Context->CurrAttr +
Context->CurrAttr->Length);
+        if (Context->CurrAttr < Context->LastAttr &&
+            Context->CurrAttr->Type != AttributeEnd)
+        {
+            return Context->CurrAttr;
+        }
+    }
+
+    if (Context->NonResidentStart == NULL)
+    {
+        Context->CurrAttr = (PVOID)-1;
+        return NULL;
+    }
+
+    if (Context->CurrAttr < Context->NonResidentStart ||
+        Context->CurrAttr >= Context->NonResidentEnd)
+    {
+        Context->CurrAttr = Context->NonResidentStart;
+    }
+    else if (Context->CurrAttr->Length != 0)
+    {
+        Context->CurrAttr = (PNTFS_ATTR_RECORD)((ULONG_PTR)Context->CurrAttr +
Context->CurrAttr->Length);
+    }
+    else
+    {
+        DPRINT1("Broken length!\n");
+        Context->CurrAttr = (PVOID)-1;
+        return NULL;
+    }
+
+    if (Context->CurrAttr < Context->NonResidentEnd &&
+        Context->CurrAttr->Type != AttributeEnd)
+    {
+        return Context->CurrAttr;
+    }
+
+    Context->CurrAttr = (PVOID)-1;
+    return NULL;
+}
+
+NTSTATUS
+FindFirstAttribute(PFIND_ATTR_CONTXT Context,
+                   PDEVICE_EXTENSION Vcb,
+                   PFILE_RECORD_HEADER FileRecord,
+                   BOOLEAN OnlyResident,
+                   PNTFS_ATTR_RECORD * Attribute)
+{
+    NTSTATUS Status;
+
+    DPRINT("FindFistAttribute(%p, %p, %p, %p, %u, %p)\n", Context, Vcb,
FileRecord, OnlyResident, Attribute);
+
+    Context->Vcb = Vcb;
+    Context->OnlyResident = OnlyResident;
+    Context->FirstAttr = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->AttributeOffset);
+    Context->CurrAttr = Context->FirstAttr;
+    Context->LastAttr = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->BytesInUse);
+    Context->NonResidentStart = NULL;
+    Context->NonResidentEnd = NULL;
+
+    if (Context->FirstAttr->Type == AttributeEnd)
+    {
+        Context->CurrAttr = (PVOID)-1;
+        return STATUS_END_OF_FILE;
+    }
+    else if (Context->FirstAttr->Type == AttributeAttributeList)
+    {
+        Status = InternalReadNonResidentAttributes(Context);
+        if (!NT_SUCCESS(Status))
+        {
+            return Status;
+        }
+
+        *Attribute = InternalGetNextAttribute(Context);
+        if (*Attribute == NULL)
+        {
+            return STATUS_END_OF_FILE;
+        }
+    }
+    else
+    {
+        *Attribute = Context->CurrAttr;
+    }
+
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS
+FindNextAttribute(PFIND_ATTR_CONTXT Context,
+                  PNTFS_ATTR_RECORD * Attribute)
+{
+    NTSTATUS Status;
+
+    DPRINT("FindNextAttribute(%p, %p)\n", Context, Attribute);
+
+    *Attribute = InternalGetNextAttribute(Context);
+    if (*Attribute == NULL)
+    {
+        return STATUS_END_OF_FILE;
+    }
+
+    if (Context->CurrAttr->Type != AttributeAttributeList)
+    {
+        return STATUS_SUCCESS;
+    }
+
+    Status = InternalReadNonResidentAttributes(Context);
+    if (!NT_SUCCESS(Status))
+    {
+        return Status;
+    }
+
+    *Attribute = InternalGetNextAttribute(Context);
+    if (*Attribute == NULL)
+    {
+        return STATUS_END_OF_FILE;
+    }
+
+    return STATUS_SUCCESS;
+}
+
+VOID
+FindCloseAttribute(PFIND_ATTR_CONTXT Context)
+{
+    if (Context->NonResidentStart != NULL)
+    {
+        ExFreePoolWithTag(Context->NonResidentStart, TAG_NTFS);
+        Context->NonResidentStart = NULL;
+    }
+}
 
 static
 VOID
@@ -341,27 +543,33 @@
 NtfsDumpFileAttributes(PDEVICE_EXTENSION Vcb,
                        PFILE_RECORD_HEADER FileRecord)
 {
+    NTSTATUS Status;
+    FIND_ATTR_CONTXT Context;
     PNTFS_ATTR_RECORD Attribute;
 
-    Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->AttributeOffset);
-    while (Attribute < (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->BytesInUse) &&
-           Attribute->Type != AttributeEnd)
+    Status = FindFirstAttribute(&Context, Vcb, FileRecord, FALSE, &Attribute);
+    while (NT_SUCCESS(Status))
     {
         NtfsDumpAttribute(Vcb, Attribute);
 
-        Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)Attribute + Attribute->Length);
-    }
+        Status = FindNextAttribute(&Context, &Attribute);
+    }
+
+    FindCloseAttribute(&Context);
 }
 
 PFILENAME_ATTRIBUTE
-GetFileNameFromRecord(PFILE_RECORD_HEADER FileRecord, UCHAR NameType)
-{
+GetFileNameFromRecord(PDEVICE_EXTENSION Vcb,
+                      PFILE_RECORD_HEADER FileRecord,
+                      UCHAR NameType)
+{
+    FIND_ATTR_CONTXT Context;
     PNTFS_ATTR_RECORD Attribute;
     PFILENAME_ATTRIBUTE Name;
-
-    Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->AttributeOffset);
-    while (Attribute < (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->BytesInUse) &&
-           Attribute->Type != AttributeEnd)
+    NTSTATUS Status;
+
+    Status = FindFirstAttribute(&Context, Vcb, FileRecord, FALSE, &Attribute);
+    while (NT_SUCCESS(Status))
     {
         if (Attribute->Type == AttributeFileName)
         {
@@ -370,50 +578,57 @@
                 (Name->NameType == NTFS_FILE_NAME_WIN32_AND_DOS && NameType ==
NTFS_FILE_NAME_WIN32) ||
                 (Name->NameType == NTFS_FILE_NAME_WIN32_AND_DOS && NameType ==
NTFS_FILE_NAME_DOS))
             {
+                FindCloseAttribute(&Context);
                 return Name;
             }
         }
 
-        Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)Attribute + Attribute->Length);
-    }
-
+        Status = FindNextAttribute(&Context, &Attribute);
+    }
+
+    FindCloseAttribute(&Context);
     return NULL;
 }
 
 PSTANDARD_INFORMATION
-GetStandardInformationFromRecord(PFILE_RECORD_HEADER FileRecord)
-{
+GetStandardInformationFromRecord(PDEVICE_EXTENSION Vcb,
+                                 PFILE_RECORD_HEADER FileRecord)
+{
+    NTSTATUS Status;
+    FIND_ATTR_CONTXT Context;
     PNTFS_ATTR_RECORD Attribute;
     PSTANDARD_INFORMATION StdInfo;
 
-    Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->AttributeOffset);
-    while (Attribute < (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->BytesInUse) &&
-           Attribute->Type != AttributeEnd)
+    Status = FindFirstAttribute(&Context, Vcb, FileRecord, FALSE, &Attribute);
+    while (NT_SUCCESS(Status))
     {
         if (Attribute->Type == AttributeStandardInformation)
         {
             StdInfo = (PSTANDARD_INFORMATION)((ULONG_PTR)Attribute +
Attribute->Resident.ValueOffset);
+            FindCloseAttribute(&Context);
             return StdInfo;
         }
 
-        Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)Attribute + Attribute->Length);
-    }
-
+        Status = FindNextAttribute(&Context, &Attribute);
+    }
+
+    FindCloseAttribute(&Context);
     return NULL;
 }
 
 PFILENAME_ATTRIBUTE
-GetBestFileNameFromRecord(PFILE_RECORD_HEADER FileRecord)
+GetBestFileNameFromRecord(PDEVICE_EXTENSION Vcb,
+                          PFILE_RECORD_HEADER FileRecord)
 {
     PFILENAME_ATTRIBUTE FileName;
 
-    FileName = GetFileNameFromRecord(FileRecord, NTFS_FILE_NAME_POSIX);
+    FileName = GetFileNameFromRecord(Vcb, FileRecord, NTFS_FILE_NAME_POSIX);
     if (FileName == NULL)
     {
-        FileName = GetFileNameFromRecord(FileRecord, NTFS_FILE_NAME_WIN32);
+        FileName = GetFileNameFromRecord(Vcb, FileRecord, NTFS_FILE_NAME_WIN32);
         if (FileName == NULL)
         {
-            FileName = GetFileNameFromRecord(FileRecord, NTFS_FILE_NAME_DOS);
+            FileName = GetFileNameFromRecord(Vcb, FileRecord, NTFS_FILE_NAME_DOS);
         }
     }
 

Modified: trunk/reactos/drivers/filesystems/ntfs/create.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/c…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/create.c	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/create.c	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -135,7 +135,7 @@
             break;
         }
 
-        FileName = GetBestFileNameFromRecord(MftRecord);
+        FileName = GetBestFileNameFromRecord(DeviceExt, MftRecord);
         if (FileName == NULL)
         {
             DPRINT1("$FILE_NAME attribute not found for %I64x\n", Id);

Modified: trunk/reactos/drivers/filesystems/ntfs/dirctl.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/d…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/dirctl.c	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/dirctl.c	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -73,7 +73,7 @@
 
     DPRINT("NtfsGetNameInformation() called\n");
 
-    FileName = GetBestFileNameFromRecord(FileRecord);
+    FileName = GetBestFileNameFromRecord(DeviceExt, FileRecord);
     if (FileName == NULL)
     {
         DPRINT1("No name information for file ID: %#I64x\n", MFTIndex);
@@ -107,7 +107,7 @@
 
     DPRINT("NtfsGetDirectoryInformation() called\n");
 
-    FileName = GetBestFileNameFromRecord(FileRecord);
+    FileName = GetBestFileNameFromRecord(DeviceExt, FileRecord);
     if (FileName == NULL)
     {
         DPRINT1("No name information for file ID: %#I64x\n", MFTIndex);
@@ -115,7 +115,7 @@
         return STATUS_OBJECT_NAME_NOT_FOUND;
     }
 
-    StdInfo = GetStandardInformationFromRecord(FileRecord);
+    StdInfo = GetStandardInformationFromRecord(DeviceExt, FileRecord);
     ASSERT(StdInfo != NULL);
 
     Length = FileName->NameLength * sizeof (WCHAR);
@@ -156,7 +156,7 @@
 
     DPRINT("NtfsGetFullDirectoryInformation() called\n");
 
-    FileName = GetBestFileNameFromRecord(FileRecord);
+    FileName = GetBestFileNameFromRecord(DeviceExt, FileRecord);
     if (FileName == NULL)
     {
         DPRINT1("No name information for file ID: %#I64x\n", MFTIndex);
@@ -164,7 +164,7 @@
         return STATUS_OBJECT_NAME_NOT_FOUND;
     }
 
-    StdInfo = GetStandardInformationFromRecord(FileRecord);
+    StdInfo = GetStandardInformationFromRecord(DeviceExt, FileRecord);
     ASSERT(StdInfo != NULL);
 
     Length = FileName->NameLength * sizeof (WCHAR);
@@ -206,16 +206,16 @@
 
     DPRINT("NtfsGetBothDirectoryInformation() called\n");
 
-    FileName = GetBestFileNameFromRecord(FileRecord);
+    FileName = GetBestFileNameFromRecord(DeviceExt, FileRecord);
     if (FileName == NULL)
     {
         DPRINT1("No name information for file ID: %#I64x\n", MFTIndex);
         NtfsDumpFileAttributes(DeviceExt, FileRecord);
         return STATUS_OBJECT_NAME_NOT_FOUND;
     }
-    ShortFileName = GetFileNameFromRecord(FileRecord, NTFS_FILE_NAME_DOS);
-
-    StdInfo = GetStandardInformationFromRecord(FileRecord);
+    ShortFileName = GetFileNameFromRecord(DeviceExt, FileRecord, NTFS_FILE_NAME_DOS);
+
+    StdInfo = GetStandardInformationFromRecord(DeviceExt, FileRecord);
     ASSERT(StdInfo != NULL);
 
     Length = FileName->NameLength * sizeof (WCHAR);

Modified: trunk/reactos/drivers/filesystems/ntfs/fcb.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/f…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/fcb.c	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/fcb.c	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -319,7 +319,7 @@
         return NULL;
     }
 
-    FileName = GetFileNameFromRecord(MftRecord, NTFS_FILE_NAME_WIN32);
+    FileName = GetFileNameFromRecord(Vcb, MftRecord, NTFS_FILE_NAME_WIN32);
     if (!FileName)
     {
         ExFreePoolWithTag(MftRecord, TAG_NTFS);
@@ -387,7 +387,7 @@
 
     DPRINT1("NtfsMakeFCBFromDirEntry(%p, %p, %wZ, %p, %p, %p)\n", Vcb,
DirectoryFCB, Name, Stream, Record, fileFCB);
 
-    FileName = GetBestFileNameFromRecord(Record);
+    FileName = GetBestFileNameFromRecord(Vcb, Record);
     if (!FileName)
     {
         return STATUS_OBJECT_NAME_NOT_FOUND; // Not sure that's the best here
@@ -428,7 +428,7 @@
     rcFCB->RFCB.ValidDataLength.QuadPart = Size;
     rcFCB->RFCB.AllocationSize.QuadPart = AllocatedSize;
 
-    StdInfo = GetStandardInformationFromRecord(Record);
+    StdInfo = GetStandardInformationFromRecord(Vcb, Record);
     if (StdInfo != NULL)
     {
         rcFCB->Entry.FileAttributes |= StdInfo->FileAttribute;

Modified: trunk/reactos/drivers/filesystems/ntfs/finfo.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/f…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/finfo.c	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/finfo.c	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -22,6 +22,7 @@
  * PURPOSE:          NTFS filesystem driver
  * PROGRAMMERS:      Eric Kohl
  *                   Hervé Poussineau (hpoussin(a)reactos.org)
+ *                   Pierre Schweitzer (pierre(a)reactos.org)
  */
 
 /* INCLUDES *****************************************************************/
@@ -225,9 +226,10 @@
                         PFILE_STREAM_INFORMATION StreamInfo,
                         PULONG BufferLength)
 {
-    NTSTATUS Status;
     ULONG CurrentSize;
+    FIND_ATTR_CONTXT Context;
     PNTFS_ATTR_RECORD Attribute;
+    NTSTATUS Status, BrowseStatus;
     PFILE_RECORD_HEADER FileRecord;
     PFILE_STREAM_INFORMATION CurrentInfo = StreamInfo, Previous = NULL;
 
@@ -249,10 +251,8 @@
         return Status;
     }
 
-    Status = STATUS_SUCCESS;
-    Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->AttributeOffset);
-    while (Attribute < (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->BytesInUse) &&
-           Attribute->Type != AttributeEnd)
+    BrowseStatus = FindFirstAttribute(&Context, DeviceExt, FileRecord, FALSE,
&Attribute);
+    while (NT_SUCCESS(BrowseStatus))
     {
         if (Attribute->Type == AttributeData)
         {
@@ -281,9 +281,10 @@
             *BufferLength -= CurrentSize;
         }
 
-        Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)Attribute + Attribute->Length);
-    }
-
+        BrowseStatus = FindNextAttribute(&Context, &Attribute);
+    }
+
+    FindCloseAttribute(&Context);
     ExFreePoolWithTag(FileRecord, TAG_NTFS);
     return Status;
 }

Modified: trunk/reactos/drivers/filesystems/ntfs/fsctl.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/f…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/fsctl.c	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/fsctl.c	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -570,6 +570,8 @@
     PIO_STACK_LOCATION Stack;
     PNTFS_VOLUME_DATA_BUFFER DataBuffer;
     PNTFS_ATTR_RECORD Attribute;
+    FIND_ATTR_CONTXT Context;
+    NTSTATUS Status;
 
     DataBuffer = (PNTFS_VOLUME_DATA_BUFFER)Irp->AssociatedIrp.SystemBuffer;
     Stack = IoGetCurrentIrpStackLocation(Irp);
@@ -595,9 +597,8 @@
     DataBuffer->MftZoneStart.QuadPart = 0; // FIXME
     DataBuffer->MftZoneEnd.QuadPart = 0; // FIXME
 
-    Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)DeviceExt->MasterFileTable +
DeviceExt->MasterFileTable->AttributeOffset);
-    while (Attribute < (PNTFS_ATTR_RECORD)((ULONG_PTR)DeviceExt->MasterFileTable +
DeviceExt->MasterFileTable->BytesInUse) &&
-           Attribute->Type != AttributeEnd)
+    Status = FindFirstAttribute(&Context, DeviceExt, DeviceExt->MasterFileTable,
FALSE, &Attribute);
+    while (NT_SUCCESS(Status))
     {
         if (Attribute->Type == AttributeData)
         {
@@ -607,8 +608,9 @@
             break;
         }
 
-        Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)Attribute + Attribute->Length);
-    }
+        Status = FindNextAttribute(&Context, &Attribute);
+    }
+    FindCloseAttribute(&Context);
 
     Irp->IoStatus.Information = sizeof(NTFS_VOLUME_DATA_BUFFER);
 

Modified: trunk/reactos/drivers/filesystems/ntfs/mft.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/m…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/mft.c	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/mft.c	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -79,95 +79,6 @@
 }
 
 
-PNTFS_ATTR_CONTEXT
-FindAttributeHelper(PDEVICE_EXTENSION Vcb,
-                    PNTFS_ATTR_RECORD AttrRecord,
-                    PNTFS_ATTR_RECORD AttrRecordEnd,
-                    ULONG Type,
-                    PCWSTR Name,
-                    ULONG NameLength)
-{
-    DPRINT("FindAttributeHelper(%p, %p, %p, 0x%x, %S, %u)\n", Vcb, AttrRecord,
AttrRecordEnd, Type, Name, NameLength);
-
-    while (AttrRecord < AttrRecordEnd)
-    {
-        DPRINT("AttrRecord->Type = 0x%x\n", AttrRecord->Type);
-
-        if (AttrRecord->Type == AttributeEnd)
-            break;
-
-        if (AttrRecord->Type == AttributeAttributeList)
-        {
-            PNTFS_ATTR_CONTEXT Context;
-            PNTFS_ATTR_CONTEXT ListContext;
-            PVOID ListBuffer;
-            ULONGLONG ListSize;
-            PNTFS_ATTR_RECORD ListAttrRecord;
-            PNTFS_ATTR_RECORD ListAttrRecordEnd;
-
-            ListContext = PrepareAttributeContext(AttrRecord);
-
-            ListSize = AttributeDataLength(&ListContext->Record);
-            if(ListSize <= 0xFFFFFFFF)
-                ListBuffer = ExAllocatePoolWithTag(NonPagedPool, (ULONG)ListSize,
TAG_NTFS);
-            else
-                ListBuffer = NULL;
-
-            if(!ListBuffer)
-            {
-                DPRINT("Failed to allocate memory: %x\n", (ULONG)ListSize);
-                continue;
-            }
-
-            ListAttrRecord = (PNTFS_ATTR_RECORD)ListBuffer;
-            ListAttrRecordEnd = (PNTFS_ATTR_RECORD)((PCHAR)ListBuffer + ListSize);
-
-            if (ReadAttribute(Vcb, ListContext, 0, ListBuffer, (ULONG)ListSize) ==
ListSize)
-            {
-                Context = FindAttributeHelper(Vcb, ListAttrRecord, ListAttrRecordEnd,
-                                              Type, Name, NameLength);
-
-                ReleaseAttributeContext(ListContext);
-                ExFreePoolWithTag(ListBuffer, TAG_NTFS);
-
-                if (Context != NULL)
-                {
-                    if (AttrRecord->IsNonResident) DPRINT("Found context =
%p\n", Context);
-                    return Context;
-                }
-            }
-        }
-
-        if (AttrRecord->Type == Type)
-        {
-            if (AttrRecord->NameLength == NameLength)
-            {
-                PWCHAR AttrName;
-
-                AttrName = (PWCHAR)((PCHAR)AttrRecord + AttrRecord->NameOffset);
-                DPRINT("%.*S, %.*S\n", AttrRecord->NameLength, AttrName,
NameLength, Name);
-                if (RtlCompareMemory(AttrName, Name, NameLength << 1) ==
(NameLength << 1))
-                {
-                    /* Found it, fill up the context and return. */
-                    DPRINT("Found context\n");
-                    return PrepareAttributeContext(AttrRecord);
-                }
-            }
-        }
-
-        if (AttrRecord->Length == 0)
-        {
-            DPRINT("Null length attribute record\n");
-            return NULL;
-        }
-        AttrRecord = (PNTFS_ATTR_RECORD)((PCHAR)AttrRecord + AttrRecord->Length);
-    }
-
-    DPRINT("Ended\n");
-    return NULL;
-}
-
-
 NTSTATUS
 FindAttribute(PDEVICE_EXTENSION Vcb,
               PFILE_RECORD_HEADER MftRecord,
@@ -176,21 +87,36 @@
               ULONG NameLength,
               PNTFS_ATTR_CONTEXT * AttrCtx)
 {
-    PNTFS_ATTR_RECORD AttrRecord;
-    PNTFS_ATTR_RECORD AttrRecordEnd;
+    NTSTATUS Status;
+    FIND_ATTR_CONTXT Context;
+    PNTFS_ATTR_RECORD Attribute;
 
     DPRINT("FindAttribute(%p, %p, 0x%x, %S, %u, %p)\n", Vcb, MftRecord, Type,
Name, NameLength, AttrCtx);
 
-    AttrRecord = (PNTFS_ATTR_RECORD)((PCHAR)MftRecord + MftRecord->AttributeOffset);
-    AttrRecordEnd = (PNTFS_ATTR_RECORD)((PCHAR)MftRecord +
Vcb->NtfsInfo.BytesPerFileRecord);
-
-    *AttrCtx = FindAttributeHelper(Vcb, AttrRecord, AttrRecordEnd, Type, Name,
NameLength);
-    if (*AttrCtx == NULL)
-    {
-        return STATUS_OBJECT_NAME_NOT_FOUND;
-    }
-
-    return STATUS_SUCCESS;
+    Status = FindFirstAttribute(&Context, Vcb, MftRecord, FALSE, &Attribute);
+    while (NT_SUCCESS(Status))
+    {
+        if (Attribute->Type == Type && Attribute->NameLength ==
NameLength)
+        {
+            PWCHAR AttrName;
+
+            AttrName = (PWCHAR)((PCHAR)Attribute + Attribute->NameOffset);
+            DPRINT("%.*S, %.*S\n", Attribute->NameLength, AttrName,
NameLength, Name);
+            if (RtlCompareMemory(AttrName, Name, NameLength << 1) == (NameLength
<< 1))
+            {
+                /* Found it, fill up the context and return. */
+                DPRINT("Found context\n");
+                *AttrCtx = PrepareAttributeContext(Attribute);
+                FindCloseAttribute(&Context);
+                return STATUS_SUCCESS;
+            }
+        }
+
+        Status = FindNextAttribute(&Context, &Attribute);
+    }
+
+    FindCloseAttribute(&Context);
+    return STATUS_OBJECT_NAME_NOT_FOUND;
 }
 
 

Modified: trunk/reactos/drivers/filesystems/ntfs/ntfs.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/n…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/ntfs.h	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/ntfs.h	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -462,6 +462,17 @@
 
 } NTFS_FCB, *PNTFS_FCB;
 
+typedef struct _FIND_ATTR_CONTXT
+{
+    PDEVICE_EXTENSION Vcb;
+    BOOLEAN OnlyResident;
+    PNTFS_ATTR_RECORD FirstAttr;
+    PNTFS_ATTR_RECORD CurrAttr;
+    PNTFS_ATTR_RECORD LastAttr;
+    PNTFS_ATTR_RECORD NonResidentStart;
+    PNTFS_ATTR_RECORD NonResidentEnd;
+} FIND_ATTR_CONTXT, *PFIND_ATTR_CONTXT;
+
 extern PNTFS_GLOBAL_DATA NtfsGlobalData;
 
 FORCEINLINE
@@ -487,16 +498,35 @@
           ULONGLONG *DataRunLength);
 
 VOID
-NtfsDumpFileAttributes(PDEVICE_EXTENSION Vcb, PFILE_RECORD_HEADER FileRecord);
+NtfsDumpFileAttributes(PDEVICE_EXTENSION Vcb,
+                       PFILE_RECORD_HEADER FileRecord);
 
 PSTANDARD_INFORMATION
-GetStandardInformationFromRecord(PFILE_RECORD_HEADER FileRecord);
+GetStandardInformationFromRecord(PDEVICE_EXTENSION Vcb,
+                                 PFILE_RECORD_HEADER FileRecord);
 
 PFILENAME_ATTRIBUTE
-GetFileNameFromRecord(PFILE_RECORD_HEADER FileRecord, UCHAR NameType);
+GetFileNameFromRecord(PDEVICE_EXTENSION Vcb,
+                      PFILE_RECORD_HEADER FileRecord,
+                      UCHAR NameType);
 
 PFILENAME_ATTRIBUTE
-GetBestFileNameFromRecord(PFILE_RECORD_HEADER FileRecord);
+GetBestFileNameFromRecord(PDEVICE_EXTENSION Vcb,
+                          PFILE_RECORD_HEADER FileRecord);
+
+NTSTATUS
+FindFirstAttribute(PFIND_ATTR_CONTXT Context,
+                   PDEVICE_EXTENSION Vcb,
+                   PFILE_RECORD_HEADER FileRecord,
+                   BOOLEAN OnlyResident,
+                   PNTFS_ATTR_RECORD * Attribute);
+
+NTSTATUS
+FindNextAttribute(PFIND_ATTR_CONTXT Context,
+                  PNTFS_ATTR_RECORD * Attribute);
+
+VOID
+FindCloseAttribute(PFIND_ATTR_CONTXT Context);
 
 /* blockdev.c */
 

Modified: trunk/reactos/drivers/filesystems/ntfs/rw.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/filesystems/ntfs/r…
==============================================================================
--- trunk/reactos/drivers/filesystems/ntfs/rw.c	[iso-8859-1] (original)
+++ trunk/reactos/drivers/filesystems/ntfs/rw.c	[iso-8859-1] Wed Aug 26 18:20:04 2015
@@ -98,13 +98,14 @@
     Status = FindAttribute(DeviceExt, FileRecord, AttributeData, Fcb->Stream,
wcslen(Fcb->Stream), &DataContext);
     if (!NT_SUCCESS(Status))
     {
+        NTSTATUS BrowseStatus;
+        FIND_ATTR_CONTXT Context;
         PNTFS_ATTR_RECORD Attribute;
 
         DPRINT1("No '%S' data stream associated with file!\n",
Fcb->Stream);
 
-        Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->AttributeOffset);
-        while (Attribute < (PNTFS_ATTR_RECORD)((ULONG_PTR)FileRecord +
FileRecord->BytesInUse) &&
-               Attribute->Type != AttributeEnd)
+        BrowseStatus = FindFirstAttribute(&Context, DeviceExt, FileRecord, FALSE,
&Attribute);
+        while (NT_SUCCESS(BrowseStatus))
         {
             if (Attribute->Type == AttributeData)
             {
@@ -116,8 +117,9 @@
                 DPRINT1("Data stream: '%wZ' available\n", &Name);
             }
 
-            Attribute = (PNTFS_ATTR_RECORD)((ULONG_PTR)Attribute +
Attribute->Length);
-        }
+            BrowseStatus = FindNextAttribute(&Context, &Attribute);
+        }
+        FindCloseAttribute(&Context);
 
         ReleaseAttributeContext(DataContext);
         ExFreePoolWithTag(FileRecord, TAG_NTFS);