Linux Kernel Indirection Table and Hash Key Leak Vulnerability in Ethtool RSS Handling

A vulnerability in the Linux kernel's ethtool component allows for a memory leak of the indirection table and hash key. This issue arises in the RSS (Receive Side Scaling) handling, specifically within the 'rss_prepare_get' function. The vulnerability is present in the stable branch of the Linux kernel. When 'rss_prepare_get' allocates the indirection table and hash key buffer, it relies on the 'rss_get_data_alloc' function. After allocation, it calls 'ops->get_rxfh()' to populate the data. However, if 'get_rxfh()' fails, the function returns an error without freeing the previously allocated memory, leading to a resource leak.

Impact

The vulnerability causes a memory leak, where allocated resources are not properly released, potentially leading to increased memory usage and degradation of system performance over time.

Reproduction

To reproduce this vulnerability, invoke the 'rss_prepare_get' function in the ethtool RSS context. Ensure that the 'ops->get_rxfh()' call fails after the indirection table and hash key have been allocated. The function will return an error without freeing the allocated resources, causing a memory leak.

Remediation

Users can apply the latest patches available in the Linux kernel stable tree to address this vulnerability.