DEBIAN-CVE-2026-80925

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    DEBIAN-CVE-2026-80925

    Published: 9 Sept 2026Last Modified: 12 Sept 2026
    Upstream:

    Summary:

    Details: In the Linux kernel, the following vulnerability has been resolved: vlan: fix skb_under_panic and races when toggling HW VLAN offload Toggling hardware VLAN TX offload (NETIF_F_HW_VLAN_CTAG_TX or NETIF_F_HW_VLAN_STAG_TX) on a lower device invokes vlan_transfer_features(), which dynamically changed vlandev->hard_header_len. This causes two issues: 1. Lockless TX paths (e.g. packet_snd in af_packet.c, ip6_finish_output2) read dev->hard_header_len without holding RTNL lock. Mutating hard_header_len dynamically under RTNL creates a data race where upper layers reserve insufficient headroom based on a stale hard_header_len, resulting in skb_under_panic when vlan_dev_hard_header() is called. 2. In addition, vlan_transfer_features() updated hard_header_len without updating header_ops, causing a mismatch between allocated headroom and header creation. Always setting dev->hard_header_len = real_dev->hard_header_len and dev->needed_headroom = real_dev->needed_headroom + VLAN_HLEN unconditionally ensures: - dev->hard_header_len remains 100% static and immutable at real_dev->hard_header_len, eliminating all dynamic runtime updates and data races on hard_header_len. - Upper layers allocating skbs via LL_RESERVED_SPACE() will always reserve sufficient headroom for software VLAN tag insertion (real_dev->hard_header_len + real_dev->needed_headroom + VLAN_HLEN). - vlandev inherits real_dev->needed_tailroom so underlying trailer/padding/ICV requirements are honored. - AF_PACKET SOCK_RAW network header offsets remain correctly aligned at real_dev->hard_header_len. - vlan_header_ops is used unconditionally. Note to stable teams: Make sure to backport these commits: e16e960d55a4 ("ipvlan: inherit needed_headroom and needed_tailroom from phy_dev") cef51860becd ("macvlan: inherit needed_headroom and needed_tailroom from lowerdev")

    Affected packages

    Package

    Name: linux

    Purl: pkg:deb/debian/linux?arch=source&distro=bookworm

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -None

    Affected versions

    6.1.106-1
    6.1.106-2
    6.1.106-3
    6.1.112-1
    6.1.115-1
    6.1.119-1
    6.1.123-1
    6.1.124-1
    6.1.128-1
    6.1.129-1
    6.1.133-1
    6.1.135-1
    6.1.137-1
    6.1.139-1
    6.1.140-1
    6.1.147-1
    6.1.148-1
    6.1.153-1
    6.1.158-1
    6.1.159-1
    6.1.162-1
    6.1.164-1
    6.1.170-1
    6.1.170-2
    6.1.170-3
    6.1.172-1
    6.1.174-1
    6.1.176-1
    6.1.177-1
    6.1.180-1
    6.1.187-1
    6.1.27-1
    6.1.37-1
    6.1.38-1
    6.1.38-2
    6.1.38-2~bpo11+1
    6.1.38-3
    6.1.38-4
    6.1.38-4~bpo11+1
    6.1.52-1
    6.1.55-1
    6.1.55-1~bpo11+1
    6.1.64-1
    6.1.66-1
    6.1.67-1
    6.1.69-1
    6.1.69-1~bpo11+1
    6.1.76-1
    6.1.76-1~bpo11+1
    6.1.82-1
    6.1.85-1
    6.1.90-1
    6.1.90-1~bpo11+1
    6.1.94-1
    6.1.94-1~bpo11+1
    6.1.98-1
    6.1.99-1

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    DEBIAN-CVE-2026-80925 | CVE-DB