04/04: [NTOSKRNL] Only allow page file on a few specific device types

[Pierre Schweitzer]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=12e8d7fe0e4e45f802ae5…

commit 12e8d7fe0e4e45f802ae5db29e755d5ad184d1a9
Author:     Pierre Schweitzer <pierre(a)reactos.org>
AuthorDate: Thu Aug 16 19:00:22 2018 +0200
Commit:     Pierre Schweitzer <pierre(a)reactos.org>
CommitDate: Thu Aug 16 19:00:22 2018 +0200

    [NTOSKRNL] Only allow page file on a few specific device types
---
 ntoskrnl/mm/pagefile.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/ntoskrnl/mm/pagefile.c b/ntoskrnl/mm/pagefile.c
index 985557825f..0649f0f2c2 100644
--- a/ntoskrnl/mm/pagefile.c
+++ b/ntoskrnl/mm/pagefile.c
@@ -364,6 +364,7 @@ NtCreatePagingFile(IN PUNICODE_STRING FileName,
     SECURITY_DESCRIPTOR SecurityDescriptor;
     PACL Dacl;
     PWSTR Buffer;
+    DEVICE_TYPE DeviceType;
 
     DPRINT("NtCreatePagingFile(FileName %wZ, MinimumSize %I64d)\n",
            FileName, MinimumSize->QuadPart);
@@ -727,6 +728,17 @@ NtCreatePagingFile(IN PUNICODE_STRING FileName,
         return Status;
     }
 
+    /* Only allow page file on a few device types */
+    DeviceType = IoGetRelatedDeviceObject(FileObject)->DeviceType;
+    if (DeviceType != FILE_DEVICE_DISK_FILE_SYSTEM && DeviceType !=
FILE_DEVICE_NETWORK_FILE_SYSTEM &&
+        DeviceType != FILE_DEVICE_DFS_VOLUME && DeviceType !=
FILE_DEVICE_DFS_FILE_SYSTEM)
+    {
+        ObDereferenceObject(FileObject);
+        ZwClose(FileHandle);
+        ExFreePoolWithTag(Buffer, TAG_MM);
+        return Status;
+    }
+
     /* Deny page file creation on a floppy disk */
     FsDeviceInfo.Characteristics = 0;
     IoQueryVolumeInformation(FileObject, FileFsDeviceInformation, sizeof(FsDeviceInfo),
&FsDeviceInfo, &Count);