CVE-2021-47301: igb: Fix use-after-free error during reset

Severity: high (CVSS 7.8 v3.1)
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: 2024-05-21 · updated 2026-06-17
Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: igb: Fix use-after-free error during reset Cleans the next descriptor to watch (next_to_watch) when cleaning the TX ring. Failure to do so can cause invalid memory accesses. If igb_poll() runs while the controller is reset this can lead to the driver try to free a skb that was already freed. (The crash is harder to reproduce with the igb driver, but the same potential problem exists as the code is identical to igc)

Affected products

Linux kernel: from 4.12 before 4.14.241; from 4.15 before 4.19.199; from 4.20 before 5.4.136; from 5.5 before 5.10.54; from 5.11 before 5.13.6; 5.14-rc1 — fixed in 4.14.241, 4.19.199, 5.10.54, 5.13.6, 5.4.136

How to fix

Upgrade to a fixed version: Linux kernel 4.14.241, 4.19.199, 5.10.54, 5.13.6. Check the vendor advisory for mitigations.

References

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