---
id: CVE-2026-46207
title: 'vsock/virtio: fix empty payload in tap skb for non-linear buffers'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  vsock/virtio: fix empty payload in tap skb for non-linear buffers

  For non-linear skbs, virtio_transport_build_skb() goes through
  virtio_transport_copy_nonlinear_skb() …
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 4b0bf10eb077cb43c09746251ef3608d62c45667 <
    06747f52ab157591cec7e5623a759473b66ef6f6
  - >-
    Linux >= 4b0bf10eb077cb43c09746251ef3608d62c45667 <
    52da6a74ca3de0fcda60301096b71534b3b18641
  - >-
    Linux >= 4b0bf10eb077cb43c09746251ef3608d62c45667 <
    378b131a25bd1a5ee27ca199fe486c299d5350c5
  - >-
    Linux >= 4b0bf10eb077cb43c09746251ef3608d62c45667 <
    3a3e3d90cbc79600544536723911657730759af3
  - Linux 6.7
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T16:11:59.640569Z'
published: '2026-05-28'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T16:13:44.671Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-46207'
references:
  - url: 'https://git.kernel.org/stable/c/06747f52ab157591cec7e5623a759473b66ef6f6'
  - url: 'https://git.kernel.org/stable/c/52da6a74ca3de0fcda60301096b71534b3b18641'
  - url: 'https://git.kernel.org/stable/c/378b131a25bd1a5ee27ca199fe486c299d5350c5'
  - url: 'https://git.kernel.org/stable/c/3a3e3d90cbc79600544536723911657730759af3'
tags:
  - cve.org
epss: 0.00127
epssPercentile: 0.02428
ingestedAt: '2026-11-06T16:57:43.324Z'
---

## Overview

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

vsock/virtio: fix empty payload in tap skb for non-linear buffers

For non-linear skbs, virtio_transport_build_skb() goes through
virtio_transport_copy_nonlinear_skb() to copy the original payload
in the new skb to be delivered to the vsockmon tap device.
This manually initializes an iov_iter but does not set iov_iter.count.
Since the iov_iter is zero-initialized, the copy length is zero and no
payload is actually copied to the monitor interface, leaving data
un-initialized.

Fix this by removing the linear vs non-linear split and using
skb_copy_datagram_iter() with iov_iter_kvec() for all cases, as
vhost-vsock already does. This handles both linear and non-linear skbs,
properly initializes the iov_iter, and removes the now unused
virtio_transport_copy_nonlinear_skb().

While touching this code, let's also check the return value of
skb_copy_datagram_iter(), even though it's unlikely to fail.

## Affected

- `Linux >= 4b0bf10eb077cb43c09746251ef3608d62c45667 < 06747f52ab157591cec7e5623a759473b66ef6f6`
- `Linux >= 4b0bf10eb077cb43c09746251ef3608d62c45667 < 52da6a74ca3de0fcda60301096b71534b3b18641`
- `Linux >= 4b0bf10eb077cb43c09746251ef3608d62c45667 < 378b131a25bd1a5ee27ca199fe486c299d5350c5`
- `Linux >= 4b0bf10eb077cb43c09746251ef3608d62c45667 < 3a3e3d90cbc79600544536723911657730759af3`
- `Linux 6.7`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.