CVE-2026-74744
Description
In the Linux kernel, the following vulnerability has been resolved: ipvlan: inherit needed_headroom and needed_tailroom from phy_dev ipvlan devices inherit hard_header_len from phy_dev during ipvlan_init(), but leave needed_headroom and needed_tailroom set to 0. When the underlying phy_dev (or stacked lower device) requires extra headroom or tailroom for headers/trailers (e.g. macsec, ipsec, wireguard, tunnels, or veth with rx headroom), upper layers calculating packet headroom and tailroom fail to reserve sufficient space. This can result in reallocation overhead, skb headroom underflows, or KASAN slab-use-after-free crashes when dev_hard_header() / ipvlan_hard_header() prepends header data or when lower devices append tailroom. Fix this by: 1. Inheriting needed_headroom and needed_tailroom from phy_dev in ipvlan_init(). 2. Propagating needed_headroom and needed_tailroom updates to attached ipvlans in ipvlan_device_event() when receiving NETDEV_FEAT_CHANGE events.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://git.kernel.org/stable/c/af602c4d0ee548da18e2409b4b4da1079625a372
- https://git.kernel.org/stable/c/f3c17ff65f54781cde696e16a6c577615ed735aa
- https://git.kernel.org/stable/c/c0fbe31f6b20ade0465130685859faa5c86fda59
- https://git.kernel.org/stable/c/5f33188457bbcc1b11ca87084037963c516ed3d9
- https://git.kernel.org/stable/c/5c2ca77212eb38559b0353b8363b7a84f4b019dd
- https://git.kernel.org/stable/c/e16e960d55a40d36bd7c2494cc005e757dc9a1ef
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.