CVE-2021-47224

net: ll_temac: Make sure to free skb when it is completely used

HIGH
7.8
CVSS Score
Published: May 21, 2024 at 02:19 PM UTC
Updated: August 5, 2026 at 09:24 AM UTC
1 product affected across 1 vendorLinux Kernel

Using Linux by Linux?

Get instant alerts when new vulnerabilities affect Linux - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.8
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: net: ll_temac: Make sure to free skb when it is completely used With the skb pointer piggy-backed on the TX BD, we have a simple and efficient way to free the skb buffer when the frame has been transmitted. But in order to avoid freeing the skb while there are still fragments from the skb in use, we need to piggy-back on the TX BD of the skb, not the first. Without this, we are doing use-after-free on the DMA side, when the first BD of a multi TX BD packet is seen as completed in xmit_done, and the remaining BDs are still being processed.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 5.4.1282.6.31 ≤ v < 5.10.462.6.31 ≤ v < 5.12.132.6.31 ≤ v < 5.132.6.31 ≤ v < 5.4.1285.11 ≤ v < 5.12.135.5 ≤ v < 5.10.465.13 rc15.13 rc25.13 rc35.13 rc45.13 rc55.13 rc692744989533cbe85e8057935d230e128810168ce
Vendor states this is fixed in 019ab7d044d0ebf97e1236bb8935b7809be92358 (fixed)
Vendor states this is fixed in 6aa32217a9a446275440ee8724b1ecaf1838df47 (fixed)
Vendor states this is fixed in 6d120ab4dc39a543c6b63361e1d0541c382900a3 (fixed)
Vendor states this is fixed in e8afe05bd359ebe12a61dbdc94c06c00ea3e8d4b (fixed)
Vendor states this is fixed in 2.6.31 (unaffected)
Vendor states this is fixed in 5.10.46 (unaffected)
Vendor states this is fixed in 5.12.13 (unaffected)
Vendor states this is fixed in 5.13 (unaffected)
Vendor states this is fixed in 5.4.128 (unaffected)

References (4)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/019ab7d044d0ebf97e1236bb8935b7809be92358
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/6aa32217a9a446275440ee8724b1ecaf1838df47
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/6d120ab4dc39a543c6b63361e1d0541c382900a3
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/e8afe05bd359ebe12a61dbdc94c06c00ea3e8d4b

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.8HIGHLinux
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-416

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card