PT-2026-61441 · Linux · Linux

CVE-2026-64124

Published

2026-07-19

Updated

2026-07-19

CVSS v3.1

8.8

High

Vector

AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

In the Linux kernel, the following vulnerability has been resolved:

net: devmem: reject dma-buf bind with non-page-aligned size or SG length

net devmem bind dmabuf() trusts dmabuf->size and sg dma len() to be PAGE SIZE multiples without checking:

tx vec is sized dmabuf->size / PAGE SIZE, and net devmem get niov at() only bounds-checks virt addr < dmabuf->size before indexing tx vec[virt addr / PAGE SIZE]. With size = NPAGE SIZE + r (1 <= r < PAGE SIZE), sendmsg() at iov base = NPAGE SIZE passes the bound check and reads tx vec[N] -- one past.
owner->area.num niovs = len / PAGE SIZE while gen pool add owner() covers the full byte len, so a non-page-multiple non-final sg desyncs num niovs from the gen pool region for every later sg, on both RX and TX.

dma-buf does not require page-aligned sizes, so the bind path has to enforce what its own indexing assumes. Reject both with -EINVAL.

The size check is TX-only (only tx vec is sized off dmabuf->size); the SG-length check covers both directions.

Fix

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CVE-2026-64124

Linux