CVE-2022-50476
MediumIn 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.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-401CVE-2022-50476 is a Memory Leak vulnerability
What is Memory Leak?
The product does not release memory after use, causing gradual resource exhaustion. Learn more on MITRE CWE
Affected versions
Linux kernel versions
3.9
and later are affected. Fixed in
4.9.337,
4.14.303,
4.19.270,
5.4.229,
5.10.163,
5.15.86,
6.0.16,
6.1.2,
6.2
and their respective stable series.
References
The following references provide additional information about CVE-2022-50476 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/07e28a8f450217db679802ebd4de0915556ce846
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PatchKernel patch commithttps://git.kernel.org/stable/c/13286ad1c7c49c606fdcba4cf66f953a1a16c1ca
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PatchKernel patch commithttps://git.kernel.org/stable/c/14d245da57a11e80277ab455aa9b6dcc5ed38a19
Frequently asked questions
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What is CVE-2022-50476?
CVE-2022-50476 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a Memory Leak flaw (CWE-401) . It affects Linux kernel versions from 3.9 onward and has been patched in 4.9.337, 4.14.303, 4.19.270 and others. CVE-2022-50476 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2022-50476?
CVE-2022-50476 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2022-50476?
Yes — CVE-2022-50476 has been patched. Fixed versions include 4.9.337, 4.14.303, 4.19.270 and others. If you are running Linux kernel 3.9 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2022-50476 actively exploited?
No — CVE-2022-50476 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Memory Leak (CWE-401)?
The product does not release memory after use, causing gradual resource exhaustion. View CWE-401 on MITRE CWE →