fs/ntfs3: Add null pointer checks

Added null pointer checks in function ntfs_security_init.
Also added le32_to_cpu in functions ntfs_security_init and indx_read.
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

fs/ntfs3/fsntfs.c

@@ -1876,10 +1876,12 @@ int ntfs_security_init(struct ntfs_sb_info *sbi)
 		goto out;
 	}
 
-	root_sdh = resident_data_ex(attr, sizeof(struct INDEX_ROOT));
-	if (root_sdh->type != ATTR_ZERO ||
+	if(!(root_sdh = resident_data_ex(attr, sizeof(struct INDEX_ROOT))) ||
+	    root_sdh->type != ATTR_ZERO ||
 	    root_sdh->rule != NTFS_COLLATION_TYPE_SECURITY_HASH ||
-	    offsetof(struct INDEX_ROOT, ihdr) + root_sdh->ihdr.used > attr->res.data_size) {
+	    offsetof(struct INDEX_ROOT, ihdr) +
+			le32_to_cpu(root_sdh->ihdr.used) >
+			le32_to_cpu(attr->res.data_size)) {
 		err = -EINVAL;
 		goto out;
 	}
@@ -1895,10 +1897,12 @@ int ntfs_security_init(struct ntfs_sb_info *sbi)
 		goto out;
 	}
 
-	root_sii = resident_data_ex(attr, sizeof(struct INDEX_ROOT));
-	if (root_sii->type != ATTR_ZERO ||
+	if(!(root_sii = resident_data_ex(attr, sizeof(struct INDEX_ROOT))) ||
+	    root_sii->type != ATTR_ZERO ||
 	    root_sii->rule != NTFS_COLLATION_TYPE_UINT ||
-	    offsetof(struct INDEX_ROOT, ihdr) + root_sii->ihdr.used > attr->res.data_size) {
+	    offsetof(struct INDEX_ROOT, ihdr) +
+			le32_to_cpu(root_sii->ihdr.used) >
+			le32_to_cpu(attr->res.data_size)) {
 		err = -EINVAL;
 		goto out;
 	}

fs/ntfs3/index.c

@@ -1102,7 +1102,8 @@ int indx_read(struct ntfs_index *indx, struct ntfs_inode *ni, CLST vbn,
 	}
 
 	/* check for index header length */
-	if (offsetof(struct INDEX_BUFFER, ihdr) + ib->ihdr.used > bytes) {
+	if (offsetof(struct INDEX_BUFFER, ihdr) + le32_to_cpu(ib->ihdr.used) >
+	    bytes) {
 		err = -EINVAL;
 		goto out;
 	}