Linux Kernel Remoteproc Memory Leak Vulnerability in Qcom Sysmon Subdevice

A memory leak vulnerability has been identified in the Linux kernel's remoteproc subsystem, specifically within the Qcom Sysmon subdevice management. The issue arises in the 'qcom_add_sysmon_subdev()' function, where the 'kfree()' function is not called to free memory when 'of_irq_get_byname()' or 'devm_request_threaded_irq()' fail. This oversight leads to a memory leak. The vulnerability affects the Linux kernel stable tree.

Impact

The vulnerability causes a memory leak, which can lead to increased memory usage and potential exhaustion of available memory resources over time.

Reproduction

The vulnerability can be reproduced by adding a Qcom Sysmon subdevice through the 'qcom_add_sysmon_subdev()' function in the remoteproc subsystem. If the function fails to retrieve the shutdown-ack IRQ, the allocated memory for the Sysmon structure is not properly freed, causing a memory leak. This can be observed by monitoring the system's memory usage before and after the function call.

Remediation

The vulnerability has been addressed by modifying the 'qcom_add_sysmon_subdev()' function to include calls to 'kfree()' when 'of_irq_get_byname()' or 'devm_request_threaded_irq()' fail. Users can apply the latest patches available in the Linux kernel stable tree to remediate this vulnerability.