www.vusec.net
GhostRace is a comprehensive security analysis that identifies speculative execution vulnerabilities within common synchronization primitives in Linux and potentially other platforms. It reveals that Speculative Race Conditions (SRCs) can compromise architecturally race-free critical regions, enabling information leakage. The study proposes a mitigation strategy that balances security enhancement with minimal performance impact.
Main Points
Analysis of Speculative Execution
A deep analysis on speculative execution reveals vulnerabilities in synchronization primitives across Linux and potentially other platforms
Implications of SRCs
SRCs (Speculative Race Conditions) enable information leakage, challenging the foundational security assumptions of critical regions in code
Significance of GhostRace's Findings
A pioneering study, GhostRace uncovers serious flaws in current synchronization mechanisms, suggesting a reevaluation of security approaches
Proposed Mitigation Strategy
The proposed mitigation, adding an lfence instruction post-lock comparison, balances security enhancement with minimal performance impact
Insights
Exploiting Speculative Race Conditions leads to vulnerabilities such as concurrent use-after-free
Race conditions arise when multiple threads attempt to access a shared resource without proper synchronization
All common synchronization primitives can be bypassed on speculative paths
Using a Spectre-v1 attack, common synchronization primitives implemented using conditional branches can be microarchitecturally bypassed
Speculative Race Conditions allow attackers to leak information from the target software
Turning all architecturally race-free critical regions into Speculative Race Conditions
Speculative Synchronization Primitives in the Linux kernel are vulnerable
All the other common write-side synchronization primitives in the Linux kernel are ultimately implemented through a conditional branch
Speculative Concurrent Use-After-Free (SCUAF) represents a significant threat
Static scanning of the Linux kernel with Coccinelle discovered 1,283 potentially exploitable gadgets
Inter-Process Interrupt (IPI) Storming is a novel exploitation technique
It consists of infinitely flooding the victim process’s CPU core with IPIs once interrupted
Links
- GhostRace Paper (PDF)
- Systems Security Research Group at IBM Research Europe
- https://github.com/vusec/ghostrace
Images
URL
https://www.vusec.net/projects/ghostrace/