CVE-2024-42120 in Linux
Summary
by MITRE • 07/30/2024
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Check pipe offset before setting vblank
pipe_ctx has a size of MAX_PIPES so checking its index before accessing the array.
This fixes an OVERRUN issue reported by Coverity.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/07/2025
The vulnerability identified as CVE-2024-42120 affects the Linux kernel's AMD display subsystem within the direct rendering manager component. This issue specifically resides in the drm/amd/display driver where improper bounds checking occurs when handling pipe context structures. The vulnerability represents a classic buffer overread condition that could potentially lead to system instability or information disclosure. The flaw was detected through static analysis by Coverity, highlighting the importance of rigorous code review processes in security-critical kernel components. The affected code path involves accessing pipe context arrays without proper validation of array indices, creating opportunities for unauthorized memory access patterns.
The technical implementation of this vulnerability stems from the pipe_ctx structure which is designed to accommodate up to MAX_PIPES pipe contexts. When processing display pipeline operations, the code fails to validate that the pipe index being accessed falls within the valid range of the allocated array. This oversight creates a scenario where an attacker could potentially manipulate input parameters to cause array index overruns. The vulnerability manifests as a buffer overread condition that could result in reading memory beyond the allocated buffer boundaries, potentially exposing sensitive kernel data or causing unpredictable behavior. This type of flaw aligns with CWE-129 which specifically addresses insufficient bounds checking in array access operations, and represents a fundamental security weakness in kernel memory management practices.
The operational impact of this vulnerability extends beyond simple memory corruption issues as it could enable privilege escalation or system instability within graphics-intensive applications. When the AMD display driver processes multiple display pipes simultaneously, improper bounds checking could lead to data corruption in kernel memory spaces, potentially affecting the stability of the entire graphics subsystem. The vulnerability is particularly concerning in multi-display environments where multiple pipe contexts are actively managed, as the probability of triggering the overflow condition increases with system complexity. Attackers could potentially exploit this condition to gain unauthorized access to kernel memory regions or cause denial of service through system crashes. This vulnerability affects systems running Linux kernels with AMD graphics drivers, particularly those supporting multiple display outputs and complex graphics configurations.
Mitigation strategies for CVE-2024-42120 should prioritize immediate kernel updates from trusted sources to ensure the patched version resolves the bounds checking issue. System administrators should implement comprehensive monitoring of graphics driver operations to detect any anomalous behavior that might indicate exploitation attempts. The fix implemented in the kernel includes proper validation of pipe context indices against the MAX_PIPES boundary before array access operations, preventing the buffer overread condition. Organizations should also consider implementing runtime protections such as kernel address space layout randomization and stack canaries to add additional defense layers. Regular security audits of kernel components, particularly graphics drivers, should be conducted to identify similar bounds checking vulnerabilities. The remediation process should include thorough testing of updated kernel versions in controlled environments before widespread deployment to ensure compatibility with existing graphics workloads and prevent regressions in system functionality.