CVE-2025-21865: In the Linux kernel, the following vulnerability has been resolved: gtp: Suppress list corruption splat in gtp_net_exit_batch

In the Linux kernel, the following vulnerability has been resolved: gtp: Suppress list corruption splat in gtp_net_exit_batch_rtnl().

In the Linux kernel, the following vulnerability has been resolved: gtp: Suppress list corruption splat in gtp_net_exit_batch_rtnl(). Brad Spengler reported the list_del() corruption splat in gtp_net_exit_batch_rtnl(). [0] Commit eb28fd76c0a0 ("gtp: Destroy device along with udp socket's netns dismantle.") added the for_each_netdev() loop in gtp_net_exit_batch_rtnl() to destroy devices in each netns as done in geneve and ip tunnels. However, this could trigger ->dellink() twice for the same device during ->exit_batch_rtnl(). Say we have two netns A & B and gtp device B that resides in netns B but whose UDP socket is in netns A. 1. cleanup_net() processes netns A and then B. 2. gtp_net_exit_batch_rtnl() finds the device B while iterating netns A's gn->gtp_dev_list and calls ->dellink(). [ device B is not yet unlinked from netns B as unregister_netdevice_many() has not been called. ] 3. gtp_net_exit_batch_rtnl() finds the device B while iterating netns B's for_each_netdev() and calls ->dellink(). gtp_dellink() cleans up the device's hash table, unlinks the dev from gn->gtp_dev_list, and calls unregister_netdevice_queue(). Basically, calling gtp_dellin

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 0.25%, higher than 16% 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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