mitigations.md

Mitigation Strategies Analysis for gfx-rs/gfx

Mitigation Strategy: Pre-compile and Validate Shaders

• Description:

  • Step 1: Shader Pre-compilation: During the application build process, compile all shaders using a shader compiler (like glslc for Vulkan or fxc for DirectX). Store the compiled shader binaries within your application's assets. This ensures shaders are known and controlled.
  • Step 2: Remove Dynamic Compilation: Eliminate or minimize runtime shader compilation from user-provided or external sources. gfx-rs applications should ideally load pre-compiled shaders. If dynamic generation is unavoidable, isolate and scrutinize this functionality heavily.
  • Step 3: Input Sanitization (if dynamic): If dynamic shader generation is absolutely necessary (which is discouraged for security reasons in gfx-rs contexts), rigorously sanitize and validate all inputs used to construct shader code. This includes checking for malicious code injection patterns, unexpected characters, and exceeding length limits before feeding them into any shader compilation process.
  • Step 4: Shader Validation: Integrate shader validation tools (provided by driver vendors or third-party libraries like spirv-val for Vulkan) into your build pipeline and during development. Run these validators on all pre-compiled shaders to detect syntax errors, semantic issues, and potential vulnerabilities before they are used by gfx-rs at runtime.
  • Step 5: Code Review: Conduct code reviews of shader generation logic and pre-compiled shaders to identify potential vulnerabilities or logic flaws that could be exploited through gfx-rs rendering pipelines.

• Threats Mitigated:

  • Shader Injection Attacks - Severity: High (Exploiting dynamic shader compilation in gfx-rs to inject malicious shader code, leading to arbitrary GPU code execution, data breaches, or DoS).
  • Shader Vulnerabilities (e.g., buffer overflows in shaders) - Severity: High (Vulnerabilities within shaders used by gfx-rs that could be triggered by crafted inputs or rendering scenarios, leading to crashes, data corruption, or GPU-level exploits).

• Impact:

  • Shader Injection Attacks: Significantly reduces risk by eliminating or severely limiting the attack surface for injecting malicious shader code into gfx-rs pipelines.
  • Shader Vulnerabilities: Partially mitigates risk by catching common shader errors and potential vulnerabilities during the build process, before gfx-rs uses them at runtime.

• Currently Implemented:

  • Partially implemented as general good practice in many gfx-rs projects. Shaders are often pre-compiled and bundled. Basic shader validation might be performed during development but is not consistently integrated into automated workflows for gfx-rs applications.

• Missing Implementation:

  • Formal integration of shader validation tools specifically within the automated build pipeline for gfx-rs projects.
  • Strict enforcement of pre-compilation and removal of dynamic shader compilation paths where possible in gfx-rs applications.
  • Formalized input sanitization and validation procedures specifically for any remaining dynamic shader generation used with gfx-rs.

Mitigation Strategy: Limit Shader Capabilities and Complexity

• Description:

  • Step 1: Needs Analysis for gfx-rs Shaders: Carefully analyze the required functionality of each shader used in your gfx-rs rendering pipelines. Design shaders to be as simple and focused as possible, only implementing the necessary computations and operations for the intended visual effects or computations within gfx-rs.
  • Step 2: Feature Restriction in gfx-rs Shaders: Avoid using unnecessary or overly complex shader language features in gfx-rs shaders that increase the attack surface or introduce potential vulnerabilities. This might include limiting the use of dynamic indexing, complex control flow, or advanced extensions if not strictly required for the intended gfx-rs rendering.
  • Step 3: Data Access Control in gfx-rs Pipelines: Restrict shader access within gfx-rs pipelines to only the data they absolutely need. Avoid granting shaders access to sensitive or unrelated data buffers or textures managed by gfx-rs. Implement clear boundaries and data separation in your gfx-rs graphics pipeline design.
  • Step 4: Complexity Audits for gfx-rs Shaders: Periodically review shader code used in gfx-rs for unnecessary complexity. Refactor shaders to simplify logic and reduce the potential for vulnerabilities arising from overly intricate code within the gfx-rs rendering context.

• Threats Mitigated:

  • Shader Vulnerabilities (due to complex logic in gfx-rs shaders) - Severity: Medium (Increased complexity in shaders used by gfx-rs makes them harder to audit and more prone to errors that could be exploited within the graphics pipeline).
  • Resource Exhaustion (due to inefficient gfx-rs shaders) - Severity: Medium (Overly complex shaders in gfx-rs can consume excessive GPU resources, contributing to DoS when rendering with gfx-rs).

• Impact:

  • Shader Vulnerabilities (due to complex logic in gfx-rs shaders): Partially mitigates risk by reducing the likelihood of introducing vulnerabilities through complex shader code used in gfx-rs.
  • Resource Exhaustion: Partially mitigates risk by improving shader efficiency in gfx-rs pipelines and reducing GPU resource consumption during rendering.

• Currently Implemented:

  • Partially implemented as general good practice in gfx-rs development. Developers generally aim for efficient shaders for performance reasons, but formal complexity audits and feature restriction policies specifically for gfx-rs shaders are not typically in place.

• Missing Implementation:

  • Formal guidelines or policies on shader complexity and feature usage specifically for shaders used in gfx-rs applications.
  • Automated tools or linters to analyze shader complexity and flag potentially problematic features in gfx-rs shader code.
  • Regular shader complexity audits as part of the code review process for gfx-rs shader development.

Mitigation Strategy: Implement Resource Limits

• Description:

  • Step 1: Identify gfx-rs Resource Types: Determine the key graphics resources managed by gfx-rs that need to be limited, such as: GPU memory allocation used by gfx-rs buffers and textures, texture sizes (width, height, depth) created via gfx-rs, buffer sizes allocated through gfx-rs, number of draw calls submitted through gfx-rs command buffers, number of compute dispatches initiated by gfx-rs, and shader storage buffer objects (SSBOs) used in gfx-rs pipelines.
  • Step 2: Define Limits for gfx-rs Resources: Establish reasonable maximum limits for each gfx-rs resource type based on the application's requirements, target hardware capabilities, and the intended usage of gfx-rs. Consider different tiers of hardware and adjust limits accordingly if necessary for gfx-rs applications.
  • Step 3: Enforcement Mechanisms within gfx-rs Application: Implement mechanisms within your gfx-rs application to enforce these limits. This can involve:
    • Checking resource allocation requests made through gfx-rs against defined limits before making actual graphics API calls.
    • Using gfx-rs features or external libraries to query available GPU resources and adjust limits dynamically based on the gfx-rs context.
    • Implementing custom resource management systems that track resource usage within gfx-rs and enforce quotas for gfx-rs resources.
  • Step 4: Error Handling in gfx-rs Resource Management: Implement robust error handling for resource allocation failures within gfx-rs due to exceeding limits. Gracefully handle these errors in your gfx-rs application and prevent crashes. Provide informative error messages to developers or users if possible when gfx-rs resource limits are hit.

• Threats Mitigated:

  • Resource Exhaustion DoS - Severity: High (Malicious actors or buggy shaders within a gfx-rs application could intentionally or unintentionally consume all GPU resources managed by gfx-rs, causing application freeze or crash during gfx-rs rendering).

• Impact:

  • Resource Exhaustion DoS: Significantly reduces risk by preventing uncontrolled resource consumption within gfx-rs and limiting the impact of resource exhaustion attacks or bugs affecting gfx-rs rendering.

• Currently Implemented:

  • Partially implemented in some gfx-rs projects. Basic resource limits might be implicitly enforced by the application's design (e.g., fixed texture sizes used with gfx-rs), but explicit and configurable resource limits for various gfx-rs resource types are likely missing.

• Missing Implementation:

  • Explicit configuration and enforcement of resource limits for various graphics resource types managed by gfx-rs.
  • Dynamic adjustment of resource limits based on hardware capabilities or system load within the gfx-rs application context.
  • Robust error handling and reporting for resource limit violations specifically within gfx-rs resource management.

Mitigation Strategy: Compatibility Testing Across Drivers and Hardware

• Description:

  • Step 1: Define gfx-rs Test Matrix: Create a comprehensive test matrix covering a wide range of graphics drivers (from major vendors like NVIDIA, AMD, Intel) and hardware configurations (different GPUs, operating systems) that are relevant to your target users of the gfx-rs application. Include both older and newer drivers and hardware to ensure broad compatibility for your gfx-rs project.
  • Step 2: Automated Testing for gfx-rs Applications: Set up automated testing infrastructure to run your gfx-rs application on the defined test matrix. Utilize virtual machines, cloud-based testing services, or dedicated hardware labs to test gfx-rs rendering across diverse environments.
  • Step 3: Regression Testing for gfx-rs Changes: Implement regression testing to ensure that new code changes or gfx-rs library updates do not introduce compatibility issues with previously tested drivers and hardware for your gfx-rs application.
  • Step 4: Issue Tracking and Reporting for gfx-rs Compatibility: Establish a system for tracking and reporting compatibility issues discovered during testing of your gfx-rs application. Prioritize and address critical issues that could lead to crashes, rendering errors, or security vulnerabilities specifically related to gfx-rs and driver interactions.
  • Step 5: User Feedback and Monitoring for gfx-rs Issues: Encourage user feedback regarding compatibility issues encountered while using your gfx-rs application and monitor user reports to identify problems in real-world scenarios related to gfx-rs and driver combinations.

• Threats Mitigated:

  • Driver Vulnerability Exploitation (Triggered by specific driver bugs when using gfx-rs) - Severity: Medium to High (Driver bugs can be exploited to cause crashes, data corruption, or potentially system-level compromise when triggered through gfx-rs API calls).
  • Application Instability due to Driver Incompatibility with gfx-rs - Severity: Medium (Driver incompatibilities can lead to crashes, rendering errors, and unpredictable application behavior specifically when using gfx-rs for rendering).

• Impact:

  • Driver Vulnerability Exploitation: Partially mitigates risk by identifying and addressing driver-specific issues that could be exploited through gfx-rs interactions.
  • Application Instability due to Driver Incompatibility with gfx-rs: Significantly reduces risk by ensuring application stability and correct rendering across a wide range of drivers and hardware when using gfx-rs.

• Currently Implemented:

  • Partially implemented in many gfx-rs projects. Some level of manual testing on developer machines with different GPUs is likely performed, but comprehensive automated testing across a wide driver/hardware matrix specifically for gfx-rs applications is likely missing.

• Missing Implementation:

  • Automated compatibility testing infrastructure and processes specifically designed for testing gfx-rs applications across drivers and hardware.
  • Formalized test matrix and test plans for driver and hardware compatibility specifically for gfx-rs projects.
  • Systematic regression testing for compatibility issues introduced by changes in gfx-rs code or library updates.