CVE-2026-98028: eth: nfp: drop the replaced rule from the list when reprogramming fails

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-25 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: eth: nfp: drop the replaced rule from the list when reprogramming fails nfp_net_fs_add() replaces an existing rule by deleting it from the hardware, decrementing nn->fs.count and programming the new one. If nfp_net_fs_add_hw() fails the old entry stays on nn->fs.list - only the success path reaches list_replace() - so the list is one longer than nn->fs.count, and it advertises a rule whose hardware entry has already been torn down. nn->fs.count is what ETHTOOL_GRXCLSRLCNT reports, so userspace then sizes its buffer one entry short of what the GRXCLSRLALL walk wants to write. That used to overwrite one u32 past the allocation; since the walk is bounded it is a permanent -EMSGSIZE instead, as nothing ever resyncs the counter.

Affected products

Linux kernel: 6.8 — fixed in 7.3

How to fix

Upgrade to a fixed version: Linux kernel 7.3. Check the vendor advisory for mitigations.

References

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