CVE-2026-63929

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> iio: buffer: Fix DMA fence leak in iio_buffer_enqueue_dmabuf()<br /> <br /> iio_buffer_enqueue_dmabuf() allocates a struct iio_dma_fence (104 bytes,<br /> kmalloc-128) via kmalloc_obj()+dma_fence_init(), which sets the initial<br /> kref to 1. It then calls dma_resv_add_fence() which takes a second<br /> reference (kref=2), and stores a raw pointer in block-&gt;fence.<br /> <br /> On the success path the function returns without calling dma_fence_put()<br /> to release the initial reference, so every buffer enqueue permanently<br /> leaks one kmalloc-128 allocation.<br /> <br /> The iio_buffer_cleanup() work item only releases the temporary reference<br /> taken during completion signalling by iio_buffer_signal_dmabuf_done();<br /> the initial reference from dma_fence_init() is never released.<br /> <br /> With four iio_rwdev instances at 240kHz and 512 samples per buffer,<br /> this produces ~1875 kmalloc-128 allocations per second matching the<br /> observed slab growth exactly. A test with ftrace confirmed that the<br /> dma_fence_destroy event was never triggered.<br /> <br /> Fix by calling dma_fence_put() after dma_resv_add_fence(), transferring<br /> ownership of the fence to the DMA reservation object. The DMA fence then<br /> gets properly discarded after being signalled.