CVE-2023-52788 in Linux
Summary
by MITRE • 05/21/2024
In the Linux kernel, the following vulnerability has been resolved:
i915/perf: Fix NULL deref bugs with drm_dbg() calls
When i915 perf interface is not available dereferencing it will lead to NULL dereferences.
As returning -ENOTSUPP is pretty clear return when perf interface is not available.
[tursulin: added stable tag]
(cherry picked from commit 36f27350ff745bd228ab04d7845dfbffc177a889)
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 01/31/2025
The vulnerability identified as CVE-2023-52788 resides within the Linux kernel's i915 graphics driver component, specifically affecting the performance monitoring interface implementation. This issue manifests as a NULL pointer dereference condition that occurs when the i915 perf interface is not available or properly initialized. The problem stems from improper error handling within the graphics driver's debugging mechanisms, where drm_dbg() function calls attempt to dereference pointers that may be NULL when the performance monitoring subsystem is not operational. Such conditions create potential stability risks for systems utilizing Intel graphics hardware, particularly in environments where graphics performance monitoring is expected but not available.
The technical flaw represents a classic null pointer dereference vulnerability that falls under CWE-476, specifically targeting the improper handling of NULL return values from system interface functions. When the i915 driver attempts to access performance monitoring capabilities that are either disabled, unsupported, or not properly initialized, the code path fails to properly validate pointer states before dereferencing them. This behavior creates a potential crash scenario that could be exploited by malicious actors to cause denial of service conditions or potentially escalate privileges within the kernel space. The vulnerability is particularly concerning because it operates at the kernel level where such failures can compromise entire system stability and security posture.
From an operational impact perspective, this vulnerability affects Linux systems running with Intel graphics hardware that utilize the i915 driver, particularly those implementing performance monitoring features. The NULL dereference can lead to kernel panics or system crashes when the graphics subsystem attempts to log debugging information through drm_dbg() calls. Attackers could potentially exploit this condition to cause persistent system instability, especially in server environments or embedded systems where graphics performance monitoring is critical for system management. The vulnerability also impacts system reliability during normal operations, as the kernel may crash unexpectedly when performance monitoring interfaces are accessed in unavailable states.
The mitigation strategy for CVE-2023-52788 involves applying the upstream kernel patch that ensures proper error handling when the i915 perf interface is not available. The fix implements a check that returns -ENOTSUPP when performance monitoring capabilities are not accessible, rather than attempting to dereference NULL pointers. This approach aligns with established kernel development practices for handling unsupported features and follows the principle of graceful degradation. System administrators should update their kernel versions to include the patched commit 36f27350ff745bd228ab04d7845dfbffc177a889, which incorporates the stable tag and cherry-picked fixes for the specific NULL dereference conditions. The remediation process should be prioritized in environments where system stability is critical, particularly those running graphics-intensive applications or server workloads that depend on reliable kernel operation. This vulnerability demonstrates the importance of proper error handling in kernel modules and the potential for seemingly minor debugging code issues to create significant system stability concerns.