The Linux kernel's wilc1000 WiFi driver function wilc_wlan_firmware_download() allocates a dma_buffer using kmalloc() and is supposed to free it on error via a 'fail:' cleanup label. While most error paths correctly jump to this cleanup, an early failure after the first acquire_bus() call returns immediately, leaking the dma_buffer. The fix replaces this early return with a goto fail to ensure the buffer is freed properly. This vulnerability was discovered using a semantic patch tool to detect kmalloc'd local leaks on early error returns in firmware download code.

The vulnerability causes a memory leak of the dma_buffer when the bus acquisition fails early in the firmware download process. While this does not directly lead to code execution or privilege escalation, repeated leaks could degrade system stability or exhaust kernel memory resources over time.

A fix has been implemented in the Linux kernel source code to replace the early return with a goto fail statement, ensuring proper cleanup of the dma_buffer. Users should update to a Linux kernel version that includes this fix once it is released. Patch status is not yet confirmed in this data; check the official Linux kernel advisories for the specific fixed version.