The Linux kernel's iio_buffer_enqueue_dmabuf() function allocates a DMA fence structure with an initial reference count of 1, then dma_resv_add_fence() adds a second reference. However, on successful execution, the function returns without releasing the initial reference, causing a permanent memory leak of kmalloc-128 allocations. This leak accumulates rapidly under typical usage scenarios, as confirmed by slab growth and ftrace analysis showing dma_fence_destroy was never triggered. The fix involves calling dma_fence_put() after dma_resv_add_fence() to transfer ownership correctly and allow proper cleanup.

The vulnerability causes a memory leak in the kernel's iio buffer subsystem, leading to continuous growth of allocated memory (kmalloc-128 slabs) during normal operation. This can degrade system performance or stability over time due to resource exhaustion. There is no indication of direct code execution or privilege escalation from this leak.

A fix has been implemented in the Linux kernel to call dma_fence_put() after dma_resv_add_fence(), ensuring proper release of the DMA fence reference and preventing the memory leak. Users should apply the official kernel update containing this fix. Patch status is not explicitly stated in the provided data; check the vendor or kernel mailing list advisories for the exact fixed versions and update accordingly.