# CVE-2025-38637: net\_sched: skbprio: Remove overly strict queue assertions

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2025-04-18 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 4.19

## Description

In the Linux kernel, the following vulnerability has been resolved: net_sched: skbprio: Remove overly strict queue assertions In the current implementation, skbprio enqueue/dequeue contains an assertion that fails under certain conditions when SKBPRIO is used as a child qdisc under TBF with specific parameters. The failure occurs because TBF sometimes peeks at packets in the child qdisc without actually dequeuing them when tokens are unavailable. This peek operation creates a discrepancy between the parent and child qdisc queue length counters. When TBF later receives a high-priority packet, SKBPRIO's queue length may show a different value than what's reflected in its internal priority queue tracking, triggering the assertion. The fix removes this overly strict assertions in SKBPRIO, they are not necessary at all.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
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## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/7abc8318ce0712182bf0783dcfdd9a6a8331160e
- https://git.kernel.org/stable/c/1284733bab736e598341f1d3f3b94e2a322864a8
- https://git.kernel.org/stable/c/32ee79682315e6d3c99947b3f38b078a09a66919
- https://git.kernel.org/stable/c/1dcc144c322a8d526b791135604c0663f1af9d85
- https://git.kernel.org/stable/c/864ca690ff135078d374bd565b9872f161c614bc
- https://git.kernel.org/stable/c/2f35b7673a3aa3d09b3eb05811669622ebaa98ca
- https://git.kernel.org/stable/c/2286770b07cb5268c03d11274b8efd43dff0d380
- https://git.kernel.org/stable/c/034b293bf17c124fec0f0e663f81203b00aa7a50
- https://git.kernel.org/stable/c/ce8fe975fd99b49c29c42e50f2441ba53112b2e8

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Page: https://cve.now/CVE-2025-38637
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