Linux Kernel DMA Mapping Leak Vulnerability in K1 Ethernet MAC

A vulnerability in the Linux kernel's handling of DMA mappings for the K1 Ethernet MAC has been addressed. When a mapping error occurred, the DMA mappings were improperly retained, leading to a memory leak. This issue has been fixed by ensuring that the leaked mappings are freed using the existing emac_free_tx_buf() function.

Impact

The vulnerability could lead to a memory leak by failing to properly release DMA mappings when a mapping error occurs, potentially causing increased memory usage or exhaustion.

Reproduction

The vulnerability can be reproduced by triggering a mapping error in the emac_tx_mem_map() function for the K1 Ethernet MAC. This will cause the DMA mappings to leak, as they are not properly freed on error.

Remediation

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