CVE-2024-46815 in Linux
Summary
by MITRE • 09/27/2024
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check num_valid_sets before accessing reader_wm_sets[]
[WHY & HOW]
num_valid_sets needs to be checked to avoid a negative index when accessing reader_wm_sets[num_valid_sets - 1].
This fixes an OVERRUN issue reported by Coverity.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 11/19/2025
The vulnerability identified as CVE-2024-46815 resides within the Linux kernel's graphics subsystem, specifically within the amdgpu display driver component. This issue manifests as a potential out-of-bounds memory access condition that could compromise system stability and security. The flaw exists in the display management code responsible for handling memory bandwidth calculations for AMD graphics hardware, where improper validation of array indices leads to memory corruption. The vulnerability was detected through static analysis tools and reported via Coverity's automated scanning processes, highlighting the importance of proper input validation in kernel-space code. The affected code path involves the drm/amd/display driver module which manages display timing and memory bandwidth calculations for AMD Radeon graphics adapters.
The technical root cause of this vulnerability stems from a missing bounds check in the memory bandwidth calculation logic. When processing display configuration data, the driver accesses the reader_wm_sets array using an index derived from num_valid_sets without first verifying that this value is positive and within acceptable bounds. The problematic code attempts to access reader_wm_sets[num_valid_sets - 1] without ensuring that num_valid_sets is greater than zero, which can result in a negative array index. This condition creates an out-of-bounds memory access pattern that could potentially allow attackers to read or write data outside the intended memory boundaries. The flaw represents a classic buffer over-read vulnerability that aligns with CWE-129, which addresses improper validation of array indices. The vulnerability specifically impacts the graphics subsystem's ability to properly manage memory bandwidth requests for display operations, potentially affecting video rendering, display output, and system stability during graphics-intensive operations.
The operational impact of CVE-2024-46815 extends beyond simple memory corruption, as it represents a potential vector for privilege escalation and system instability. When the kernel encounters this condition, it may trigger kernel oops, system crashes, or memory corruption that could be exploited to gain unauthorized access to system resources. The vulnerability affects systems running Linux kernels with AMD graphics hardware, particularly those utilizing the amdgpu driver for display management. Attackers could potentially leverage this flaw to cause denial of service conditions or in more sophisticated scenarios, exploit the memory corruption to execute arbitrary code with kernel privileges. The issue is particularly concerning in server environments or systems where graphics processing is critical, as it could lead to complete system compromise. According to ATT&CK framework category T1068, this vulnerability could enable privilege escalation through kernel exploitation techniques, while T1499 covers potential system disruption through denial of service conditions.
Mitigation strategies for CVE-2024-46815 primarily involve applying the official kernel patches that implement proper bounds checking before array access operations. System administrators should prioritize updating to kernel versions that contain the fix, which typically includes the addition of a conditional check to verify that num_valid_sets is positive before accessing reader_wm_sets[num_valid_sets - 1]. The patch implementation follows standard secure coding practices by ensuring that all array accesses are validated against their respective bounds. Organizations should also consider implementing additional monitoring for kernel-level anomalies and system crashes that may indicate exploitation attempts. While no specific exploit code has been reported for this vulnerability, the nature of the flaw suggests it could be weaponized given sufficient knowledge of the target system's graphics configuration. The fix demonstrates proper adherence to secure coding principles and represents a defensive programming approach that prevents buffer overflows through explicit validation of input parameters. Regular kernel updates and vulnerability assessments remain critical for maintaining system security posture against similar issues in the graphics subsystem.