Method and system for designating and handling confidential memory allocations

• US 8,631,250 B2
• Filed: 03/28/2012
• Issued: 01/14/2014
• Est. Priority Date: 02/28/2006
• Status: Active Grant

• Current Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Original Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Inventors: Van Riel, Henri Han, Cox, Alan
• Primary Examiner(s): ARMOUCHE, HADI S
• Application Number:
  US13/432,488
• Publication Number:
  US 20120185953A1
• Time in Patent Office: 657 Days
• Field of Search: None
• US Class Current: 713/193
• CPC Class Codes: G06F 12/023 Free address space management
• CPC Class Codes: G06F 12/08 in hierarchically structured memory systems, e.g. virtual memory systems
• CPC Class Codes: G06F 12/126 with special data handling, e.g. priority of data or instructions, handling errors or pinning
• CPC Class Codes: G06F 12/145 the protection being virtual, e.g. for virtual blocks or segments before a translation mechanism
• CPC Class Codes: G06F 21/78 to assure secure storage of data address-based protection against unauthorised use of memory G06F12/14; record carriers for use with machines and with at least a part designed to carry digital markings G06K19/00

Abstract

Designating and handling confidential memory allocations of virtual memory. An operating system provides a memory allocation flag that applications may use to indicate any arbitrary area of physical memory marked with this flag may contain confidential data and should be handled accordingly. The operating system also ensures that memory allocated with this flag can be placed in physical memory. When freeing up memory, the operating system protects any data in the memory allocated with this flag. For example, the operating system may prevent the confidential memory from being swapped out to storage or from being accessible to other applications, such as debuggers. Alternatively, the operating system may encrypt any data in the confidential memory before it is swapped out to storage.

Claims

1. A method, comprising:

storing, by one or more processors, confidential data in a confidential section of virtual memory, wherein storing the confidential data in the confidential section of virtual memory comprises;

mapping the confidential section of virtual memory to an address space in a first physical memory device;

storing the confidential data in the first physical memory device; and

marking the address space in the first physical memory device as having confidential data;

receiving a request to copy data stored in the address space in the first physical memory device to a second physical memory device;

determining that the address space in the first physical memory device has been marked as having confidential data; and

denying the request to copy in response to determining that the address space in the first physical memory device has been marked as having confidential data.

2. The method of claim 1, wherein the request to copy data stored in the address space in the first physical memory device is received as a result of a power-saving operation.

3. The method of claim 2, the operations further comprising:

copying data stored in non-confidential sections of the virtual memory to the second physical device;

completing the power-saving operation; and

upon resuming from the power-saving operation;

determining one or more processes had been using the confidential data; and

providing a warning to the one or more processes that the confidential data was not copied to the second physical memory device.

4. The method of claim 2, the operations further comprising:

copying data stored in non-confidential sections of the virtual memory to the second physical device;

completing the power-saving operation; and

upon resuming from the power-saving operation;

determining one or more processes had been using the confidential data; and

terminating the one or more processes.

10. The method of claim 1, wherein the second physical memory device has more capacity and slower memory access speed than the first physical memory device.

11. The method of claim 1, wherein the request to copy data stored in the address space in the first physical memory device is received as a result of a cache miss.

5. A system, comprising:

one or more processors; and

a memory system operatively coupled with the one or more processors, wherein the memory system comprises at least a first physical memory device and a second physical memory device, and wherein the one or more processors to perform operations comprising;

storing confidential data in a confidential section of virtual memory, wherein storing the confidential data in the confidential section of virtual memory comprises;

mapping the confidential section of virtual memory to an address space in the first physical memory device;

storing the confidential data in the first physical memory device; and

marking the address space in the first physical memory device as having confidential data;

receiving a request to copy data stored in the address space in the first physical memory device to the second physical memory device;

determining that the address space in the first physical memory device has been marked as having confidential data; and

denying the request to copy in response to determining that the address space in the first physical memory device has been marked as having confidential data.

6. The system of claim 5, wherein the request to copy data stored in the address space in the first physical memory device is received as a result of a power-saving operation.

7. The system of claim 6, wherein the one or more processors are to further perform operations comprising:

copying data stored in non-confidential sections of the virtual memory to the second physical device;

completing the power-saving operation; and

upon resuming from the power-saving operation;

determining one or more processes had been using the confidential data; and

providing a warning to the one or more processes that the confidential data was not copied to the second physical memory device.

8. The system of claim 6, wherein the one or more processors are to further perform operations comprising:

copying data stored in non-confidential sections of the virtual memory to the second physical device;

completing the power-saving operation; and

upon resuming from the power-saving operation;

determining one or more processes had been using the confidential data; and

terminating the one or more processes.

9. The system of claim 5, wherein the second physical memory device has more capacity and slower memory access speed than the first physical memory device.

12. The system of claim 5, wherein the request to copy data stored in the address space in the first physical memory device is received as a result of a cache miss.