CVE-2025-21799: In the Linux kernel, the following vulnerability has been resolved: net: ethernet: ti: am65-cpsw: fix freeing IRQ in am65_cpsw_nuss_remove_tx

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: ti: am65-cpsw: fix freeing IRQ in am65_cpsw_nuss_remove_tx_chns() When gett

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: ti: am65-cpsw: fix freeing IRQ in am65_cpsw_nuss_remove_tx_chns() When getting the IRQ we use k3_udma_glue_tx_get_irq() which returns negative error value on error. So not NULL check is not sufficient to deteremine if IRQ is valid. Check that IRQ is greater then zero to ensure it is valid. There is no issue at probe time but at runtime user can invoke .set_channels which results in the following call chain. am65_cpsw_set_channels() am65_cpsw_nuss_update_tx_rx_chns() am65_cpsw_nuss_remove_tx_chns() am65_cpsw_nuss_init_tx_chns() At this point if am65_cpsw_nuss_init_tx_chns() fails due to k3_udma_glue_tx_get_irq() then tx_chn->irq will be set to a negative value. Then, at subsequent .set_channels with higher channel count we will attempt to free an invalid IRQ in am65_cpsw_nuss_remove_tx_chns() leading to a kernel warning. The issue is present in the original commit that introduced this driver, although there, am65_cpsw_nuss_update_tx_rx_chns() existed as am65_cpsw_nuss_update_tx_chns().

Description from the National Vulnerability Database, published by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

What it means for a small business

Linux is on the computers, phones or browsers your team uses every day. Turn on automatic updates and restart: most of these fixes only take effect after a restart.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.23%, higher than 13% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

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Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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