Riskcovery

CVE-2025-21954

netmem: prevent TX of unreadable skbs

State
Published
Severity
9.8 Critical
Published
Apr 1, 2025
Updated
Aug 5, 2026
Reserved
Dec 29, 2024

Read the record on cve.org

Description

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

netmem: prevent TX of unreadable skbs

Currently on stable trees we have support for netmem/devmem RX but not TX. It is not safe to forward/redirect an RX unreadable netmem packet into the device's TX path, as the device may call dma-mapping APIs on dma addrs that should not be passed to it.

Fix this by preventing the xmit of unreadable skbs.

Tested by configuring tc redirect:

sudo tc qdisc add dev eth1 ingress sudo tc filter add dev eth1 ingress protocol ip prio 1 flower ip_proto \ tcp src_ip 192.168.1.12 action mirred egress redirect dev eth1

Before, I see unreadable skbs in the driver's TX path passed to dma mapping APIs.

After, I don't see unreadable skbs in the driver's TX path passed to dma mapping APIs.

Scores

CVSSScoreVectorSource
3.19.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HLinux

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • 65249feb6b3df9e17bab5911ee56fa7b0971e231 to before 454825019d2f0c59e5174ece9e713f45ad80beffAffected
  • 65249feb6b3df9e17bab5911ee56fa7b0971e231 to before 1c17c8ced25c5fbe424c7ad7ea11d33014a986b1Affected
  • 65249feb6b3df9e17bab5911ee56fa7b0971e231 to before f3600c867c99a2cc8038680ecf211089c50e7971Affected
LinuxLinux
  • 6.12Affected
  • before 6.12Not affected
  • 6.12.20 through 6.12.*Not affected
  • 6.13.8 through 6.13.*Not affected
  • 6.14 and laterNot affected

References

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