[pschweitzer] 64793: [NTFS] Bugfixing... Part 4/X: - Fix a nasty bug in NtfsLookupFileAt() (how did it work before?). The name parsing was wrong (no progress was being made) and thus was leading to...

Author: pschweitzer
Date: Fri Oct 17 22:17:59 2014
New Revision: 64793

URL: http://svn.reactos.org/svn/reactos?rev=64793&view=rev
Log:
[NTFS]
Bugfixing... Part 4/X:
- Fix a nasty bug in NtfsLookupFileAt() (how did it work before?). The name parsing was
wrong (no progress was being made) and thus was leading to an infinite loop in directory
browsing.
- Fix a lovely bug coming from a non-documented feature in NTFS. To properly read the MFT
index, you've to apply a mask. Do this to properly handles MFT record. This fixes
returned MFT index which allows resuse.
- Do not allow returning MFT records < 0x10 for now. Not sure whether it should be
allowed, but so far, these are MFT special records, so let's forget about it. IIRC,
they are available on Windows. But trying to chase another bug for the moment.

This does not fix yet directory enumeration.

Modified:
    trunk/reactos/drivers/filesystems/ntfs/mft.c
    trunk/reactos/drivers/filesystems/ntfs/ntfs.h

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] Fri Oct 17 22:17:59 2014
@@ -548,9 +548,11 @@
         while (IndexEntry < IndexEntryEnd &&
                !(IndexEntry->Flags & NTFS_INDEX_ENTRY_END))
         {
-            if (CurrentEntry >= *FirstEntry && CompareFileName(FileName,
IndexEntry, DirSearch))
-            {
-                *OutMFTIndex = IndexEntry->Data.Directory.IndexedFile;
+            if ((IndexEntry->Data.Directory.IndexedFile & NTFS_MFT_MASK) > 0x10
&&
+                CurrentEntry >= *FirstEntry &&
+                CompareFileName(FileName, IndexEntry, DirSearch))
+            {
+                *OutMFTIndex = (IndexEntry->Data.Directory.IndexedFile &
NTFS_MFT_MASK);
                 *FirstEntry = CurrentEntry;
                 RtlCopyMemory(OutName, IndexEntry->FileName.Name,
IndexEntry->FileName.NameLength);
                 OutName[IndexEntry->FileName.NameLength / sizeof(WCHAR)] =
UNICODE_NULL;
@@ -639,10 +641,12 @@
                 while (IndexEntry < IndexEntryEnd &&
                        !(IndexEntry->Flags & NTFS_INDEX_ENTRY_END))
                 {
-                    if (CurrentEntry >= *FirstEntry &&
CompareFileName(FileName, IndexEntry, DirSearch))
+                    if ((IndexEntry->Data.Directory.IndexedFile & NTFS_MFT_MASK)
> 0x10 &&
+                        CurrentEntry >= *FirstEntry &&
+                        CompareFileName(FileName, IndexEntry, DirSearch))
                     {
                         DPRINT("File found\n");
-                        *OutMFTIndex = IndexEntry->Data.Directory.IndexedFile;
+                        *OutMFTIndex = (IndexEntry->Data.Directory.IndexedFile &
NTFS_MFT_MASK);
                         *FirstEntry = CurrentEntry;
                         RtlCopyMemory(OutName, IndexEntry->FileName.Name,
IndexEntry->FileName.NameLength);
                         OutName[IndexEntry->FileName.NameLength / sizeof(WCHAR)] =
UNICODE_NULL;
@@ -694,7 +698,7 @@
 
     while (Current.Length != 0)
     {
-        DPRINT1("Lookup: %wZ\n", &Current);
+        DPRINT1("Current: %wZ\n", &Current);
 
         Status = NtfsFindMftRecord(Vcb, CurrentMFTIndex, &Current, &FirstEntry,
FALSE, &CurrentMFTIndex, FoundName);
         if (!NT_SUCCESS(Status))
@@ -702,7 +706,10 @@
             return Status;
         }
 
-        FsRtlDissectName(*PathName, &Current, &Remaining);
+        if (Remaining.Length == 0)
+            return STATUS_OBJECT_PATH_NOT_FOUND;
+
+        FsRtlDissectName(Current, &Current, &Remaining);
     }
 
     *FileRecord = ExAllocatePoolWithTag(NonPagedPool,
Vcb->NtfsInfo.BytesPerFileRecord, TAG_NTFS);

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] Fri Oct 17 22:17:59 2014
@@ -168,6 +168,8 @@
 #define NTFS_FILE_QUOTA                9
 #define NTFS_FILE_UPCASE            10
 #define NTFS_FILE_EXTEND            11
+
+#define NTFS_MFT_MASK 0x0000FFFFFFFFFFFFULL
 
 #define COLLATION_BINARY              0x00
 #define COLLATION_FILE_NAME           0x01