CVE-2026-80925
UnknownSummary
A vulnerability in the Linux kernel's VLAN mechanism involves dynamically changing hard_header_len when toggling hardware VLAN TX offload. This causes a data race in lockless TX paths, potentially leading to skb_under_panic and a mismatch between allocated headroom and header creation.
Risk Assessment
The risk includes system panics during packet transmission over VLAN interfaces, potentially causing network service disruptions. The data race may also lead to unpredictable network stack behavior, possibly enabling DoS attacks.
Recommendation
Immediately update the Linux kernel to a version containing the fix that makes hard_header_len and needed_headroom static. Also apply the mentioned backports (e16e960d55a4, cef51860becd) in stable kernel branches.
Other vulnerabilities in Linux kernel
See all- CVE-2026-80924Unknown
In the Linux kernel, in the crypto: krb5 module, crypto_krb5_prepare_encryption() and crypto_krb5_prepare_checksum() free the buffer holding freshly derived keys with plain kfree(), leaving the key material behind in the freed slab object. This can lead to sensitive data leakage.
- CVE-2026-80923Unknown
In the Linux kernel, in the xhci: dbgtty driver, if tty_register_driver() fails, it drops the reference but fails to set the global dbc_tty_driver to NULL, causing the unregister to be called again when the module exits. This leads to a use-after-free condition.
- CVE-2026-80922Unknown
In the Linux kernel, in the crypto: qcom-rng module, the random number generator does not allow zero as an output, making its output distinguishable from truly random. Zero is a valid random number and should be allowed.
- CVE-2026-80921Unknown
In the Linux kernel, in KVM: s390 vsie, when shadowing crypto access bits from a format0 apcb (crycb 0 or 1), bits 64..255 are unchanged from whatever is in the vsie page in the crycb and thus in the apcb. This gives a nested guest potential access to a device no longer available. Zero out the remaining bits.
- CVE-2026-80920Unknown
In the Linux kernel, in io_uring, eventfd signaling is done inline when adding the first entry to the work list, which can cause issues when the addition is done from a wakeup handler context. The fix adds the IOU_F_TWQ_IN_WAKE flag to force deferral of signaling via call_rcu_hurry() instead of inline signaling.
- CVE-2026-80919Unknown
In the Linux kernel, a vulnerability was found in the amdgpu driver where amdgpu_devcoredump_format() recursively acquires a ww_mutex lock. This can lead to a deadlock when dumping IB contents from a hung job. The fix moves the operation to a separate helper using a single drm_exec context.
- CVE-2026-80918Unknown
In the Linux kernel, in HID: core, there is a number/pointer type confusion on long items. When fetch_item() is called by hid_scan_report() on an item with HID_ITEM_TAG_LONG, it stores a pointer to the item data in item->data.longdata instead of storing a value directly. Functions item_udata() and item_sdata() incorrectly assume short format, leading to the lower part of a kernel pointer being printed as a number in dmesg.
- CVE-2026-80917Unknown
A vulnerability in the Linux kernel causes a NULL pointer dereference in the PCI host-generic driver on 32-bit systems using CAM mode. During PCI bus enumeration, the first config read uses an uninitialized mapping, leading to a kernel panic. The issue stems from missing add_bus/remove_bus callbacks in the CAM operations, which are necessary for proper mapping of the config space.
- CVE-2026-80916Unknown
A vulnerability in the Linux kernel's KCOV mechanism causes data corruption and race conditions on PREEMPT_RT systems. The issue stems from storing temporary KCOV state in per-CPU areas, which can be overwritten by nested softirq preemption. Additionally, under certain initialization conditions, it may lead to kernel panic or memory leaks.
- CVE-2026-80915Unknown
In the Linux kernel, the drm/xe driver's DPT allocation paths were fixed. The fallback from VRAM to system memory was removed as it did not work and caused black screen with pipe faults. Also, stolen memory usage is avoided due to latency and risk of random system hangs under load.
Original NVD description (English source)
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")

