CVE-2022-49489 in Linux
Summary
by MITRE • 02/26/2025
In the Linux kernel, the following vulnerability has been resolved:
drm/msm/disp/dpu1: set vbif hw config to NULL to avoid use after memory free during pm runtime resume
BUG: Unable to handle kernel paging request at virtual address 006b6b6b6b6b6be3
Call trace: dpu_vbif_init_memtypes+0x40/0xb8 dpu_runtime_resume+0xcc/0x1c0 pm_generic_runtime_resume+0x30/0x44 __genpd_runtime_resume+0x68/0x7c genpd_runtime_resume+0x134/0x258 __rpm_callback+0x98/0x138 rpm_callback+0x30/0x88 rpm_resume+0x36c/0x49c __pm_runtime_resume+0x80/0xb0 dpu_core_irq_uninstall+0x30/0xb0 dpu_irq_uninstall+0x18/0x24 msm_drm_uninit+0xd8/0x16c
Patchwork: https://patchwork.freedesktop.org/patch/483255/ [DB: fixed Fixes tag]
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Analysis
by VulDB Data Team • 05/23/2025
The vulnerability identified as CVE-2022-49489 represents a critical use-after-free condition within the Linux kernel's display subsystem, specifically affecting the Qualcomm MSM display driver component known as dpu1. This flaw manifests during power management runtime resume operations when the kernel attempts to access memory that has already been freed, leading to a kernel paging fault at virtual address 0x006b6b6b6b6b6be3. The issue stems from improper memory management during the display processing unit's hardware configuration initialization process, where vbif hardware configuration pointers are not properly nullified after memory deallocation.
The technical implementation of this vulnerability occurs within the dpu_vbif_init_memtypes function, which is invoked during the dpu_runtime_resume sequence that handles power management transitions for display components. When the system attempts to resume from a low power state, the driver fails to properly null the vbif hardware configuration pointer before freeing associated memory resources. This creates a scenario where subsequent code paths may attempt to dereference the freed memory location, resulting in a kernel oops and potential system instability. The call trace demonstrates the execution flow leading to the fault, showing the path from the runtime resume handler through the generic power management subsystem to the final memory access violation.
This vulnerability presents significant operational impact as it can lead to system crashes, kernel panics, and potential denial of service conditions in devices utilizing Qualcomm MSM display controllers. The use-after-free condition creates an exploitable entry point that could potentially be leveraged by malicious actors to execute arbitrary code within kernel space, particularly affecting mobile devices, embedded systems, and IoT platforms that rely on the affected kernel versions. The flaw affects systems running Linux kernel versions where the drm/msm/disp/dpu1 subsystem is active, making it particularly concerning for automotive infotainment systems, smartphones, tablets, and other mobile computing devices with Qualcomm Snapdragon processors.
Mitigation strategies for this vulnerability involve applying the official kernel patch provided through the freedesktop.org patchwork system, which implements proper nullification of the vbif hardware configuration pointer before memory deallocation occurs. System administrators should prioritize updating to kernel versions containing the fix, typically kernel versions 5.19 and later where the patch has been integrated. Additionally, implementing runtime monitoring and memory sanitization tools can help detect similar patterns in other kernel subsystems. Organizations should also consider implementing proper kernel hardening measures including stack canaries, kernel address space layout randomization, and strict memory access controls. This vulnerability aligns with CWE-416, which describes the use of freed memory condition, and could potentially map to ATT&CK technique T1068, involving the exploitation of privileges to execute malicious code within kernel space. The fix demonstrates proper memory management practices that should be applied across all kernel subsystems handling hardware configuration pointers and runtime power management operations.