Linux Kernel Hold RCU and Device Lock Vulnerability in HSR Port Management

A vulnerability in the Linux kernel's handling of High-availability Seamless Redundancy (HSR) port management has been addressed. The issue arose because the function 'hsr_get_port_ndev' did not properly manage locks, potentially leading to a use-after-free condition. The function 'hsr_for_each_port' requires the Read-Copy Update (RCU) lock to be held, but this was not done. Additionally, before returning the port device, a reference to the device needed to be held to prevent a use-after-free error in the calling function. This vulnerability affects the Linux kernel stable tree.

Impact

The vulnerability could lead to a use-after-free condition, which may be exploitable to cause memory corruption or arbitrary code execution.

Remediation

Users can upgrade to the latest version of the Linux kernel stable tree to address this vulnerability.