Approaches for protecting sensitive data within a guest operating system

• US 9,239,909 B2
• Filed: 01/25/2012
• Issued: 01/19/2016
• Est. Priority Date: 01/25/2012
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Bromium (HP Inc.)
• Inventors: Tedesco, Gianni, Pole, Anushree, Southgate, Andrew, Pratt, Ian, Kapoor, Vikram, Banga, Gaurav
• Primary Examiner(s): Abrishamkar, Kaveh
• Assistant Examiner(s): Wilcox, James J
• Application Number:
  US13/358,434
• Publication Number:
  US 20130191924A1
• Time in Patent Office: 1,455 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 21/00 Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
• CPC Class Codes: G06F 21/53 by executing in a restricted environment, e.g. sandbox or secure virtual machine
• CPC Class Codes: G06F 21/62 Protecting access to data via a platform, e.g. using keys or access control rules
• CPC Class Codes: G06F 21/74 operating in dual or compartmented mode, i.e. at least one secure mode
• CPC Class Codes: G06F 2221/2143 Clearing memory, e.g. to prevent the data from being stolen

Abstract

Approaches for preventing unauthorized access of sensitive data within an operating system (OS), e.g., a guest OS used by a virtual machine. Dummy data may be written over physical locations on disk where sensitive data is stored, thereby preventing a malicious program from accessing the sensitive data. Alternately, a delete operation may be performed on sensitive data within an OS, and thereafter the OS is converted into a serialized format to expunge the deleted data. The serialized OS is converted into a deserialized form to facilitate its use. Optionally, a data structure may be updated to identify where sensitive data is located within an OS. When a request to access a portion of the OS is received, the data structure is consulted to determine whether the requested portion contains sensitive data, and if so, dummy data is returned to the requestor without consulting the requested portion of the OS.

Claims

1. A non-transitory computer-readable storage medium storing instructions for supplying a guest operating system to a virtual machine, which when executed by one or more processors, cause:

in response to receiving data that identifies where, within a guest operating system, sensitive data is located, updating a data structure to identify where the sensitive data is located within the guest operating system;

in response to receiving, from a requestor, a request to access a portion of the guest operating system, determining whether the data structure indicates that the requested portion of the guest operating system contains sensitive data; and

upon determining that the requested portion of the guest operating system does contain sensitive data, informing the requestor that a disk fault has occurred to cause the requestor to abort the request.

2. The non-transitory computer-readable storage medium of claim 1, wherein the data structure is a first data structure, and execution of the instructions further cause:

upon receiving a request to write data to a particular portion of the guest operating system that currently stores sensitive data, updating a second data structure to identify that the particular portion stores updated data instead of the sensitive data.

3. The non-transitory computer-readable storage medium of claim 2, wherein execution of the instructions further cause:

in response to receiving, from a second requestor, a second request to access the particular portion of the guest operating system, determining whether the second data structure identifies any updated data associated with the particular portion; and

upon the second data structure identifying updated data associated with the particular portion, performing the second request by supplying, to the second requestor, the updated data without consulting the particular portion of the guest operating system.

4. The non-transitory computer-readable storage medium of claim 2, wherein the first data structure and the second data structure are the same data structure.

5. The non-transitory computer-readable storage medium of claim 1, wherein the first data structure further identifies one or more files of the guest operating system which are not required by the virtual machine.

6. The non-transitory computer-readable storage medium of claim 1, wherein execution of the instructions further cause:

identifying where, within the operating system, the sensitive data is located based, at least in part, upon portions of the operating system that a newly added user cannot access.

7. An apparatus for supplying a guest operating system to a virtual machine, which when executed by one or more processors, comprising:

one or more processors; and

one or more non-transitory computer-readable storage mediums storing one or more sequences of instructions, which when executed, cause;

in response to receiving data that identifies where, within a guest operating system, sensitive data is located, updating a data structure to identify where the sensitive data is located within the guest operating system;

in response to receiving, from a requestor, a request to access a portion of the guest operating system, determining whether the data structure indicates that the requested portion of the guest operating system contains sensitive data; and

upon determining that the requested portion of the guest operating system does contain sensitive data, informing the requestor that a disk fault has occurred to cause the requestor to abort the request.

8. The apparatus of claim 7, wherein the data structure is a first data structure, and execution of the instructions further cause:

upon receiving a request to write data to a particular portion of the guest operating system that currently stores sensitive data, updating a second data structure to identify that the particular portion stores updated data instead of the sensitive data.

9. The apparatus of claim 8, wherein execution of the instructions further cause:

in response to receiving, from a second requestor, a second request to access the particular portion of the guest operating system, determining whether the second data structure identifies any updated data associated with the particular portion; and

upon the second data structure identifying updated data associated with the particular portion, performing the second request by supplying, to the second requestor, the updated data without consulting the particular portion of the guest operating system.

10. The apparatus of claim 8, wherein the first data structure and the second data structure are the same data structure.

11. The apparatus of claim 7, wherein the first data structure further identifies one or more files of the guest operating system which are not required by the virtual machine.

12. The apparatus of claim 7, wherein execution of the instructions further cause:

identifying where, within the operating system, the sensitive data is located based, at least in part, upon portions of the operating system that a newly added user cannot access.