Linux Kernel gs_usb Driver Memory Leak Vulnerability

A memory leak vulnerability has been identified in the Linux kernel's gs_usb driver, which is commonly seen in USB-CAN adapter drivers. The issue arises because the driver uses usb_alloc_coherent() to allocate USB request blocks (URBs) for receiving data, but later relies on usb_kill_anchored_urbs() to free them, which does not effectively release the memory. This can lead to a leakage of DMA memory used by the driver. The vulnerability has been addressed by modifying the driver to explicitly free the RX URBs and their associated DMA memory, correcting the memory management flaw.

Impact

Exploitation of this vulnerability can result in a memory leak, causing DMA memory to be improperly released and potentially leading to increased memory usage or exhaustion.