CVE-2022-50476: In the Linux kernel, the following vulnerability has been resolved: ntb_netdev: Use dev_kfree_skb_any() in interrupt context TX/RX callback handlers...

Description

In the Linux kernel, the following vulnerability has been resolved: ntb_netdev: Use dev_kfree_skb_any() in interrupt context TX/RX callback handlers (ntb_netdev_tx_handler(), ntb_netdev_rx_handler()) can be called in interrupt context via the DMA framework when the respective DMA operations have completed. As such, any calls by these routines to free skb's, should use the interrupt context safe dev_kfree_skb_any() function. Previously, these callback handlers would call the interrupt unsafe version of dev_kfree_skb(). This has not presented an issue on Intel IOAT DMA engines as that driver utilizes tasklets rather than a hard interrupt handler, like the AMD PTDMA DMA driver. On AMD systems, a kernel WARNING message is encountered, which is being issued from skb_release_head_state() due to in_hardirq() being true. Besides the user visible WARNING from the kernel, the other symptom of this bug was that TCP/IP performance across the ntb_netdev interface was very poor, i.e. approximately an order of magnitude below what was expected. With the repair to use dev_kfree_skb_any(), kernel WARNINGs from skb_release_head_state() ceased and TCP/IP performance, as measured by iperf, was on par with expected results, approximately 20 Gb/s on AMD Milan based server. Note that this performance is comparable with Intel based servers.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.14%

4.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-401

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	>= 3.9, < 4.9.337
Linux	Linux Kernel	>= 4.10, < 4.14.303
Linux	Linux Kernel	>= 4.15, < 4.19.270
Linux	Linux Kernel	>= 4.20, < 5.4.229
Linux	Linux Kernel	>= 5.5, < 5.10.163
Linux	Linux Kernel	>= 5.11, < 5.15.86
Linux	Linux Kernel	>= 5.16, < 6.0.16
Linux	Linux Kernel	>= 6.1, < 6.1.2

References

Timeline

Published: Oct 4, 2025
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2022-50476?

In the Linux kernel, the following vulnerability has been resolved: ntb_netdev: Use dev_kfree_skb_any() in interrupt context TX/RX callback handlers (ntb_netdev_tx_handler(), ntb_netdev_rx_handler()) can be called in interrupt context via the DMA framework when the respective DMA operations have completed. As such, any calls by these routines to free skb's, should use the interrupt context safe dev_kfree_skb_any() function. Previously, these callback handlers would call the interrupt unsafe version of dev_kfree_skb(). This has not presented an issue on Intel IOAT DMA engines as that driver utilizes tasklets rather than a hard interrupt handler, like the AMD PTDMA DMA driver. On AMD systems, a kernel WARNING message is encountered, which is being issued from skb_release_head_state() due to in_hardirq() being true. Besides the user visible WARNING from the kernel, the other symptom of this bug was that TCP/IP performance across the ntb_netdev interface was very poor, i.e. approximately an order of magnitude below what was expected. With the repair to use dev_kfree_skb_any(), kernel WARNINGs from skb_release_head_state() ceased and TCP/IP performance, as measured by iperf, was on par with expected results, approximately 20 Gb/s on AMD Milan based server. Note that this performance is comparable with Intel based servers.

How severe is CVE-2022-50476?

CVE-2022-50476 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.14% probability of exploitation in the next 30 days.

How do I fix CVE-2022-50476?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.