CVE-2026-63929

Katalog CVE

CVSS 5.5 · Medium EPSS 0,16%

Kerentanan Missing Release of Memory after Effective Lifetime pada linux kernel. Skor CVSS 3.1 5.5 (Medium) menurut NVD.

Deskripsi (NVD)

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

Rincian

Terbit di NVD

19 Juli 2026

Terakhir diubah

30 Oktober 2026

Status NVD

Analyzed

CVSS 3.1

5.5 (Medium), sumber NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-401: Missing Release of Memory after Effective Lifetime

EPSS (30 hari)

0,16% peluang dieksploitasi; lebih tinggi dari 5,3% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://git.kernel.org/stable/c/3412a95afaa5d3262008dfc34f3c7be33d8151dc patch
• https://git.kernel.org/stable/c/9678aeed8b77d495a417dd057d479f3733094019 patch
• https://git.kernel.org/stable/c/96cdeaba6a008503455b78a9641c05c2a886a7ec patch
• https://git.kernel.org/stable/c/a093999355084bdbfe6e97f1dd232e58a1525f0b patch