Method and system for designating and handling confidential memory allocations

• US 20070208954A1
• Filed: 02/28/2006
• Published: 09/06/2007
• 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, Cox, Alan
• Granted Patent: US 8,190,914 B2
• Time in Patent Office: Days
• 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

Embodiments of the present invention provide methods and systems for designating and handling confidential memory allocations of virtual memory. In particular, the 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 a debuggers. Alternatively, the operating system may encrypt any data in the confidential memory before it is swapped out to storage.

Claims

1. A method of protecting confidential data, said method comprising:

receiving a request to allocate space in a virtual memory for confidential data;

marking a portion of the virtual memory as confidential;

determining if a portion of a physical memory has been assigned for the confidential portion of the virtual memory; and

marking the portion of the physical memory that has been assigned for the confidential portion of the virtual memory as having confidential data.

2. The method of claim 1, wherein receiving the request to allocate confidential space in the virtual memory comprises receiving data that is marked with a flag indicating that it contains confidential data.

3. The method of claim 1, further comprising:

determining if the physical memory has space available for the confidential portion of virtual memory; and

allocating the confidential portion to the physical memory only when space is available in the physical memory.

4. The method of claim 1, further comprising preventing the confidential portion stored in the physical memory from being written to a storage device.

5. The method of claim 1, further comprising preventing the confidential portion stored in the physical memory from being written to a socket.

6. The method of claim 1, further comprising:

detecting when contents of the physical memory are being written to a storage device during a core dump; and

preventing the confidential portion stored in the physical memory from being included in the core dump.

7. The method of claim 1, further comprising:

detecting when contents of the virtual memory are being written to a storage device during a core dump; and

preventing the confidential portion of the virtual memory from being included in the core dump.

8. The method of claim 1, further comprising:

determining when at some of the confidential portion stored in the physical memory has been selected for eviction to a storage device; and

encrypting data in the confidential portion prior to eviction to the storage device.

9. An apparatus comprising means that are configured to perform the method of claim 1.

10. A computer readable medium comprising executable instructions for performing the method of claim 1.

11. A method of protecting data allocated to a confidential area of virtual memory that is stored in physical memory, said method comprising:

detecting when contents of the physical memory are being written to another location;

identifying contents of the physical memory that correspond to data allocated to the confidential area of the virtual memory; and

protecting the identified contents of the physical memory.

12. The method of claim 11, wherein detecting when contents of the physical memory are being written to another location comprises detecting when contents of the physical memory are being written to socket.

13. The method of claim 11, wherein detecting when contents of the physical memory are being written to another location comprises detecting when contents of the physical memory are being written to a storage device for a core dump.

14. The method of claim 13, further comprising preventing the contents of the physical memory that correspond to data allocated to the confidential area of the virtual memory from being written to the storage device during the core dump.

15. The method of claim 11, wherein detecting when contents of the physical memory are being written to another location comprises detecting when contents of the physical memory are being written to a storage device for transition into a power-saving mode.

16. The method of claim 15, further comprising preventing the contents of the physical memory that correspond to data allocated to the confidential area of the virtual memory from being written to the storage device during the transition into the power-saving mode.

17. The method of claim 11, wherein protecting the identified contents of the physical memory comprises preventing the identified contents from being written to a storage device.

18. The method of claim 11, wherein protecting the identified contents of the physical memory comprises encrypting the identified contents before they are written to a storage device.

19. The method of claim 11, wherein protecting the identified contents of the physical memory comprises preventing the identified contents from being accessible to a debugger.

20. The method of claim 11, further comprising providing a warning message when the identified contents have been written another location.

21. The method of claim 11, wherein protecting the identified contents of the physical memory comprises terminating a process using the identified contents when the process is being suspended.

22. The method of claim 21, further comprising resuming the process and notifying the process that its identified contents that correspond to data allocated to the confidential area of the virtual memory was discarded during the suspension of the process.

23. An apparatus comprising means that are configured to perform the method of claim 11.

24. A computer readable medium comprising computer readable instructions for performing the method of claim 11.