Heap Buffer Overflow Prevention via Link Validation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Heap buffer overflow attacks allow malicious hackers to inject unauthorized code, granting remote system access by corrupting memory links, which existing technologies fail to effectively prevent.
Innovation Solution
The method stalls heap allocation and deallocation function calls, predicts block links within the heap segment, and takes corrective action if links are found outside the segment, ensuring they point within the associated heap segment to prevent malicious code execution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If heap buffer overflow attack is launched to overwrite memory links, then unauthorized code execution is enabled, but system security is compromised
Solution Approach 1:
The patent applies preliminary action by validating heap buffer addresses and link integrity before allocating or deallocating memory blocks. The system checks whether forward and backward links point to valid addresses within the heap segment before proceeding with allocation or deallocation operations, preventing buffer overflow exploits from corrupting memory management structures.
Solution Approach 2:
The patent introduces an intermediary validation mechanism that acts as a mediator between heap operations and memory management functions. This intermediary layer verifies address validity and link integrity, blocking malicious operations while allowing legitimate memory management to proceed unchanged.
2Productivity
If existing memory management functions are used without validation, then allocation and deallocation operations are fast, but they fail to prevent buffer overflow attacks
Solution Approach 1:
The validation checks are performed as preliminary actions within the existing allocation and deallocation workflows. By integrating address validation and link verification into the function prologue, the system maintains operational speed while adding security checks that prevent buffer overflow attacks from succeeding.
Solution Approach 2:
The memory management functions perform self-validation by checking their own internal structures (forward and backward links) for integrity. This self-service approach allows the system to detect and prevent corrupted link states without requiring external validation mechanisms, maintaining both speed and security.
3Device complexity
If F-links and B-links are not validated, then memory management operations are simple, but stray links enable malicious code injection
Solution Approach 1:
The patent implements feedback by having the memory management system continuously verify the integrity of forward and backward links during allocation and deallocation operations. When invalid or stray links are detected, the system provides feedback by correcting or rejecting the operation, preventing malicious code injection while maintaining relatively simple validation logic.
Solution Approach 2:
The patent replaces complex manual validation mechanisms with automated address verification using CPU address validation capabilities. This substitution reduces the apparent complexity of memory management by leveraging hardware or OS-level address validation features to automatically verify link integrity without requiring complex software validation logic.
Data Source
AI summary
A method includes stalling a call to a heap allocation function originating from a request by an application for a block of heap buffer, predicting a block of the heap buffer to fulfill the request, and determining if a forward link (F-link) and a backward link (B-link) of the predicted block are addresses within a heap segment associated with the predicted block. If a determination is made that the F-link or the B-link point outside the associated heap segment, e.g., have been overwritten by a heap buffer overflow attack, corrective action is taken to correct the stray F-link or B-link. After the corrective action is taken, the heap allocation function call is released and the block of heap buffer is allocated. In this manner, a heap buffer overflow attack is defeated.