CVE-2026-80978
In the Linux kernel, the following vulnerability has been resolved: net: cap advertised IP tunnel headroom IP tunnel devices derive their advertised needed_hea…
Impact
In the Linux kernel, the following vulnerability has been resolved: net: cap advertised IP tunnel headroom IP tunnel devices derive their advertised needed_headroom from lower output devices. A stack of user-created devices can make the derived value larger than the 16-bit skb header offsets can represent. Once IP output reserves it, skb head expansion can wrap those offsets. The runtime transmit path already caps a growing needed_headroom at 512. Apply the same cap when tunnel configuration publishes needed_headroom derived from a lower output device. Capping the advertised value is safe: IP tunnel transmit still expands the skb when a packet needs more headroom. A nonsensical stacked configuration can therefore incur an extra reallocation, but it cannot publish an unbounded reservation to upper layers.
Affected packages
This record carries no package version data, so it cannot be matched against a dependency list automatically. Read the advisory and compare your version by hand.
References
- NVD record
- CVE.org record
- https://git.kernel.org/stable/c/6b222adeb9340306e2ff97127c76117abb9b3df8
- https://git.kernel.org/stable/c/84783961cb8bdb36b4f41a02ce43aafc6d52b176
- https://git.kernel.org/stable/c/9144f2c53a04465a6878172b523f640313c5559e
- https://git.kernel.org/stable/c/af0ee8f04bea22cdb331fa3509e17f81b48938ad
- https://git.kernel.org/stable/c/b160422f8103574425e2834130e169d84c94fa1d
- https://git.kernel.org/stable/c/bc4e05ae66c9797a0972ac44326e69c5305e0020
- https://git.kernel.org/stable/c/d36e75f5669140b66515ad3a176ca6337bd80a5e
- https://git.kernel.org/stable/c/fb889a619723032140f5d983a3a34d25a5a2bed4