[edk2] [PATCH v1 05/10] MdeModulePkg/UdfDxe: Add boundary check for getting volume (free) size

[Hao Wu]

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=828

Within GetVolumeSize():

The boundary check will validate the 'NumberOfPartitions' field of a
Logical Volume Integrity Descriptor matches the data within the relating
Logical Volume Descriptor.

Cc: Paulo Alcantara <pa...@paulo.ac>
Cc: Ruiyu Ni <ruiyu...@intel.com>
Cc: Jiewen Yao <jiewen....@intel.com>
Cc: Star Zeng <star.z...@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a...@intel.com>
---
 MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c | 17 
++++++++++++++++-
 MdeModulePkg/Universal/Disk/UdfDxe/Udf.h                  |  7 +++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c 
b/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
index 7611d28b5a..826ffccf81 100644
--- a/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
+++ b/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
@@ -2450,6 +2450,13 @@ SetFileInfo (
 /**
   Get volume and free space size information of an UDF volume.
 
+  @attention This is boundary function that may receive untrusted input.
+  @attention The input is from FileSystem.
+
+  The Logical Volume Descriptor and the Logical Volume Integrity Descriptor are
+  external inputs, so this routine will do basic validation for both 
descriptors
+  and report status.
+
   @param[in]   BlockIo        BlockIo interface.
   @param[in]   DiskIo         DiskIo interface.
   @param[in]   Volume         UDF volume information structure.
@@ -2488,7 +2495,8 @@ GetVolumeSize (
 
   ExtentAd = &LogicalVolDesc->IntegritySequenceExtent;
 
-  if (ExtentAd->ExtentLength == 0) {
+  if ((ExtentAd->ExtentLength == 0) ||
+      (ExtentAd->ExtentLength < sizeof (UDF_LOGICAL_VOLUME_INTEGRITY))) {
     return EFI_VOLUME_CORRUPTED;
   }
 
@@ -2528,6 +2536,13 @@ GetVolumeSize (
     goto Out_Free;
   }
 
+  if ((LogicalVolInt->NumberOfPartitions > MAX_UINT32 / sizeof (UINT32) / 2) ||
+      (LogicalVolInt->NumberOfPartitions * sizeof (UINT32) * 2 >
+       ExtentAd->ExtentLength - sizeof (UDF_LOGICAL_VOLUME_INTEGRITY))) {
+    Status = EFI_VOLUME_CORRUPTED;
+    goto Out_Free;
+  }
+
   *VolumeSize = 0;
   *FreeSpaceSize = 0;
 
diff --git a/MdeModulePkg/Universal/Disk/UdfDxe/Udf.h 
b/MdeModulePkg/Universal/Disk/UdfDxe/Udf.h
index 85bf5e7733..9c3f21fd05 100644
--- a/MdeModulePkg/Universal/Disk/UdfDxe/Udf.h
+++ b/MdeModulePkg/Universal/Disk/UdfDxe/Udf.h
@@ -902,6 +902,13 @@ SetFileInfo (
 /**
   Get volume and free space size information of an UDF volume.
 
+  @attention This is boundary function that may receive untrusted input.
+  @attention The input is from FileSystem.
+
+  The Logical Volume Descriptor and the Logical Volume Integrity Descriptor are
+  external inputs, so this routine will do basic validation for both 
descriptors
+  and report status.
+
   @param[in]   BlockIo        BlockIo interface.
   @param[in]   DiskIo         DiskIo interface.
   @param[in]   Volume         UDF volume information structure.
-- 
2.12.0.windows.1

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