GHSA-MH75-V23P-MCVC
Vulnerability from github – Published: 2026-06-24 18:32 – Updated: 2026-06-24 18:32In the Linux kernel, the following vulnerability has been resolved:
macvlan: fix macvlan_get_size() not reserving space for IFLA_MACVLAN_BC_CUTOFF
macvlan_get_size() does not account for IFLA_MACVLAN_BC_CUTOFF, but macvlan_fill_info() conditionally includes it when port->bc_cutoff != 1. This causes nla_put_s32() to fail with -EMSGSIZE when the netlink skb runs out of space, triggering a WARN_ON in rtnetlink and preventing the interface from being dumped.
The bug can be reproduced with:
ip link add macvlan0 link eth0 type macvlan mode bridge ip link set macvlan0 type macvlan bc_cutoff 0 ip -d link show macvlan0 # fails with -EMSGSIZE
The bc_cutoff feature was added in commit 954d1fa1ac93 ("macvlan: Add netlink attribute for broadcast cutoff"), which added the nla_put_s32() call in macvlan_fill_info() but missed adding the corresponding nla_total_size(4) in macvlan_get_size(). A follow-up commit 55cef78c244d ("macvlan: add forgotten nla_policy for IFLA_MACVLAN_BC_CUTOFF") fixed the missing nla_policy entry but still did not fix the size calculation.
{
"affected": [],
"aliases": [
"CVE-2026-53013"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-24T17:17:12Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmacvlan: fix macvlan_get_size() not reserving space for IFLA_MACVLAN_BC_CUTOFF\n\nmacvlan_get_size() does not account for IFLA_MACVLAN_BC_CUTOFF, but\nmacvlan_fill_info() conditionally includes it when port-\u003ebc_cutoff != 1.\nThis causes nla_put_s32() to fail with -EMSGSIZE when the netlink skb\nruns out of space, triggering a WARN_ON in rtnetlink and preventing the\ninterface from being dumped.\n\nThe bug can be reproduced with:\n\n ip link add macvlan0 link eth0 type macvlan mode bridge\n ip link set macvlan0 type macvlan bc_cutoff 0\n ip -d link show macvlan0 # fails with -EMSGSIZE\n\nThe bc_cutoff feature was added in commit 954d1fa1ac93 (\"macvlan: Add\nnetlink attribute for broadcast cutoff\"), which added the nla_put_s32()\ncall in macvlan_fill_info() but missed adding the corresponding\nnla_total_size(4) in macvlan_get_size(). A follow-up commit\n55cef78c244d (\"macvlan: add forgotten nla_policy for\nIFLA_MACVLAN_BC_CUTOFF\") fixed the missing nla_policy entry but still\ndid not fix the size calculation.",
"id": "GHSA-mh75-v23p-mcvc",
"modified": "2026-06-24T18:32:43Z",
"published": "2026-06-24T18:32:43Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53013"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1c004f14ccdc11585625c168bb9a7c5e1b8afb0c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4979252758387b338ca968ba7e0515b0ae2257e3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/77ecfa4e27f282d224215895ddfbeb916fc75e24"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b6b7154e9f5d75b608ceb2d05b376de8c638c40e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fa92a77b0ed4d5f11a71665a232ac5a54a4b055d"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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