diff --git a/src/add-ons/kernel/file_systems/ext2/Volume.cpp b/src/add-ons/kernel/file_systems/ext2/Volume.cpp
index 629cec7dc6..3b5925186a 100644
--- a/src/add-ons/kernel/file_systems/ext2/Volume.cpp
+++ b/src/add-ons/kernel/file_systems/ext2/Volume.cpp
@@ -202,9 +202,21 @@ DeviceOpener::GetSize(off_t* _size, uint32* _blockSize)
 bool
 ext2_super_block::IsValid()
 {
-	// TODO: check some more values!
-	if (Magic() != (uint32)EXT2_SUPER_BLOCK_MAGIC)
+	if (Magic() != (uint32)EXT2_SUPER_BLOCK_MAGIC
+			|| BlockShift() > 16
+			|| BlocksPerGroup() != (1UL << BlockShift()) * 8
+			|| InodeSize() > (1UL << BlockShift())
+			|| RevisionLevel() > EXT2_MAX_REVISION
+			|| ReservedGDTBlocks() > (1UL << BlockShift()) / 4)
 		return false;
+	if (Has64bitFeature()) {
+		if (GroupDescriptorSize() > EXT2_BLOCK_GROUP_64BIT_SIZE	 || GroupDescriptorSize() < EXT2_BLOCK_GROUP_NORMAL_SIZE)
+			return false;
+	}
+	else {
+		if (GroupDescriptorSize() != EXT2_BLOCK_GROUP_NORMAL_SIZE)
+			return false;
+	}
 	
 	return true;
 }
diff --git a/src/add-ons/kernel/file_systems/ext2/ext2.h b/src/add-ons/kernel/file_systems/ext2/ext2.h
index 2bc5f7fc29..2e7479e7fa 100644
--- a/src/add-ons/kernel/file_systems/ext2/ext2.h
+++ b/src/add-ons/kernel/file_systems/ext2/ext2.h
@@ -194,6 +194,7 @@ struct ext2_super_block {
 #define	EXT2_STATE_INVALID						0x02
 
 #define EXT2_BLOCK_GROUP_NORMAL_SIZE			32
+#define EXT2_BLOCK_GROUP_64BIT_SIZE				64
 
 // block group flags
 #define EXT2_BLOCK_GROUP_INODE_UNINIT	0x1