Selective self-healing of memory errors using allocation location information

• US 7,434,105 B1
• Filed: 11/07/2005
• Issued: 10/07/2008
• Est. Priority Date: 11/07/2005
• Status: Active Grant

• Current Assignee: Veritas Technologies, LLC (Whitehouse Group Ltd.)
• Original Assignee: Symantec Operating Corporation (NortonLifeLock Inc.)
• Inventors: Spertus, Michael P., Rodriguez-Rivera, Gustavo
• Primary Examiner(s): Maskulinski; Michael C
• Assistant Examiner(s): Miles; Neil D
• Application Number:
  US11/268,360
• Time in Patent Office: 1,065 Days
• Field of Search: 714/38
• US Class Current: 714/38.1
• CPC Class Codes: G06F 11/073 in a memory management context, e.g. virtual memory or cache management memory management G06F12/00; testing of static memory units G11C29/00
• CPC Class Codes: G06F 11/0751 Error or fault detection not based on redundancy power supply failures G06F1/30; network fault management H04L41/06
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 11/1438 Restarting or rejuvenating
• CPC Class Codes: G06F 12/023 Free address space management

Abstract

A system for selective self-healing of memory errors comprises a processor coupled to a memory, where the memory stores instructions executable by the processor to store an error record for each memory management error detected during an execution of the application. The error record identifies an allocation location (e.g., a portion of a stack trace corresponding to the invocation of a memory allocation function such as malloc( )) of an object associated with the memory management error. The instructions are executable to use the error record to identify, during subsequent execution, memory operations performed on objects allocated from the allocation location, and to perform corresponding memory protection operations (e.g., operations to prevent re-occurrences of the memory errors) for the memory operations identified using the error record.

Claims

1. A system, comprising:

a processor; and

memory coupled to the processor;

wherein the memory stores program instructions executable by the processor to;

store an error record in a database corresponding to a memory management error detected during an execution of an application, wherein the memory management error is associated with an object allocated during the execution, wherein the error record identifies an allocation location within the application at which the object was allocated;

identify, using the error record, at least one memory operation in the application performed on an other object allocated from the allocation location identified in the error record; and

perform at least one memory protection operation corresponding to the at least one memory operation identified using the error record.

2. The system as recited in claim 1, wherein the instructions are further executable to:

examine the database to determine whether a memory protection operation is to be performed for a given memory operation during an execution of the program;

in response to determining that a memory protection operation is to be performed for the given memory operation, perform the memory protection operation; and

in response to determining that a memory protection operation is not to be performed for the given memory operation, perform the given memory operation without performing a corresponding memory protection operation.

3. The system as recited in claim 1, wherein the error record indicates a type of memory protection operation to be performed for memory operations on objects allocated from the identified allocation location.

4. The system as recited in claim 1, wherein the instructions are further executable to:

store a respective identification of an allocation location corresponding to each object allocated during the execution; and

prior to storing the error record, generate the error record using a stored identification of an allocation location corresponding to the object.

5. The system as recited in claim 1, wherein the allocation location is specified in the error record as one or more program counter values.

6. The system as recited in claim 1, wherein the allocation location is specified in the error record as a portion of an execution stack.

7. The system as recited in claim 1, wherein the memory management error comprises at least one of:

a memory smash operation, a premature free operation, a duplicate free operation, a premature garbage collection operation, and a memory leak.

8. The system as recited in claim 7, wherein:

if the memory management error comprises a memory smash operation, a corresponding memory protection operation comprises allocating a number of extra bytes for the other object;

if the memory management error comprises a premature free operation or a duplicate free operation, a corresponding memory protection operation comprises designating the other object as an object to be collected via garbage collection instead of being explicitly freed;

if the memory management error comprises a premature garbage collection operation, a corresponding memory protection operation comprises designating the other object as an object to be explicitly freed instead of being collected via garbage collection; and

if the memory management error comprises a memory leak, a corresponding memory protection operation comprises generating a report of a stack trace of the application when the other object is allocated.

9. The system as recited in claim 1, wherein the instructions are further executable to:

provide an interface configured to display a representation of one or more memory management errors detected during the execution, wherein the representation comprises an identification of the type of each memory management error of the one or more memory errors.

10. The system as recited in claim 9, wherein the interface comprises a mechanism enabling a user to selectively enable and disable a use of memory protection operations corresponding to one or more types of memory management errors.

11. The system as recited in claim 1, wherein the at least one memory protection operation is performed during the same execution of the application in which the memory management error is detected.

12. The system as recited in claim 1, wherein the at least one memory protection operation is performed during a different execution of the application than the execution in which the memory management error is detected, wherein the instructions are further executable to:

generate a persistent data structure comprising the error record;

wherein the at least one memory operation is identified during the different execution using the persistent data structure.

13. The system as recited in claim 1, wherein the execution of the application comprises an invocation of one or more functions of a shared library, wherein the allocation location is within a function of the shared library.

14. A computer-implemented method, comprising:

storing an error record in a database corresponding to a memory management error detected during an execution of an application, wherein the memory management error is associated with an object allocated during the execution, wherein the error record identifies an allocation location within the application at which the object was allocated;

identifying, using the error record, at least one memory operation in the application performed on an other object allocated from the allocation location identified in the error record; and

performing at least one memory protection operation corresponding to the at least one memory operation identified using the error record.

15. The method as recited in claim 14, further comprising:

examining the database to determine whether a memory protection operation is to be performed for a given memory operation during an execution of the program;

in response to determining that a memory protection operation is to be performed for the given memory operation, performing the memory protection operation; and

in response to determining that a memory protection operation is not to be performed for the given memory operation, performing the given memory operation without performing a corresponding memory protection operation.

16. The method as recited in claim 14, further comprising:

storing a respective identification of an allocation location corresponding to each object allocated during the execution; and

prior to storing the error record, generating the error record using a stored identification of an allocation location corresponding to the object.

17. The method as recited in claim 14, wherein the allocation location is specified in the error record as one or more program counter values.

18. The method as recited in claim 14, wherein the memory management error comprises at least one of:

a memory smash operation, a premature free operation, a duplicate free operation, a premature garbage collection operation, and a memory leak.

19. The method as recited in claim 18, wherein,

if the memory management error comprises a memory smash operation, a corresponding memory protection operation comprises allocating a number of extra bytes for the other object;

if the memory management error comprises a premature free operation or a duplicate free operation, a corresponding memory protection operation comprises designating the other object as an object to be collected via garbage collection instead of being explicitly freed;

if the memory management error comprises a premature garbage collection operation, a corresponding memory protection operation comprises designating the other object as an object to be explicitly freed instead of being collected via garbage collection; and

if the memory management error comprises a memory leak, a corresponding memory protection operation comprises generating a report of a stack trace of the application when the other object is allocated.

20. A tangible computer readable medium comprising program instructions, wherein the instructions are computer-executable to:

store an error record in a database corresponding to a memory management error detected during an execution of an application, wherein the memory management error is associated with an object allocated during the execution, wherein the error record identifies an allocation location within the application at which the object was allocated;

identify, using the error record, at least one memory operation in the application performed on an other object allocated from the allocation location identified in the error record; and

perform at least one memory protection operation corresponding to the at least one memory operation identified using the error record.

21. The computer readable medium as recited in claim 20, wherein the instructions are further computer executable to:

examine the database to determine whether a memory protection operation is to be performed for a given memory operation during an execution of the program;

in response to determining that a memory protection operation is to be performed for the given memory operation, perform the memory protection operation; and

in response to determining that a memory protection operation is not to be performed for the given memory operation, perform the given memory operation without performing a corresponding memory protection operation.

22. The computer readable medium as recited in claim 20, wherein the instructions are further computer executable to:

store a respective identification of an allocation location corresponding to each object allocated during the execution; and

prior to storing the error record, generate the error record using a stored identification of an allocation location corresponding to the object.

23. The computer readable medium as recited in claim 20, wherein the allocation location is specified in the error record as a portion of a stack trace.

24. The computer readable medium as recited in claim 20, wherein the memory management error comprises at least one of:

a memory smash operation, a premature free operation, a duplicate free operation, a premature garbage collection operation, and a memory leak.

25. The computer readable medium as recited in claim 24, wherein,

if the memory management error comprises a memory smash operation, a corresponding memory protection operation comprises allocating a number of extra bytes for the other object;

if the memory management error comprises a premature free operation or a duplicate free operation, a corresponding memory protection operation comprises designating the other object as an object to be collected via garbage collection instead of being explicitly freed;

if the memory management error comprises a premature garbage collection operation, a corresponding memory protection operation comprises designating the other object as an object to be explicitly freed instead of being collected via garbage collection; and

if the memory management error comprises a memory leak, a corresponding memory protection operation comprises generating a report of a stack trace of the application when the other object is allocated.