GHSA-Q526-M4V6-PRWF
Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-19 18:32In the Linux kernel, the following vulnerability has been resolved:
can: bcm: add missing device refcount for CAN filter removal
sashiko-bot remarked a problem with a concurrent device unregistration in isotp.c which also is present in the bcm.c code. A former fix for raw.c commit c275a176e4b6 ("can: raw: add missing refcount for memory leak fix") introduced a netdevice_tracker which solves the issue for bcm.c too.
bcm_release(), bcm_delete_rx_op() and bcm_notifier() relied on dev_get_by_index(ifindex) to re-find the device for an rx_op before unregistering its filter. If a concurrent NETDEV_UNREGISTER has already unlisted the device from the ifindex table, that lookup fails and can_rx_unregister() is silently skipped, leaving a stale CAN filter pointing at the soon-to-be-freed bcm_op/socket.
Hold a netdev_hold()/netdev_put() tracked reference on op->rx_reg_dev from the moment the rx filter is registered in bcm_rx_setup() until it is unregistered in bcm_rx_unreg(), and use that reference directly in bcm_release() and bcm_delete_rx_op() instead of re-looking the device up by ifindex.
{
"affected": [],
"aliases": [
"CVE-2026-72113"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-15T06:21:25Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: bcm: add missing device refcount for CAN filter removal\n\nsashiko-bot remarked a problem with a concurrent device unregistration\nin isotp.c which also is present in the bcm.c code. A former fix for raw.c\ncommit c275a176e4b6 (\"can: raw: add missing refcount for memory leak fix\")\nintroduced a netdevice_tracker which solves the issue for bcm.c too.\n\nbcm_release(), bcm_delete_rx_op() and bcm_notifier() relied on\ndev_get_by_index(ifindex) to re-find the device for an rx_op before\nunregistering its filter. If a concurrent NETDEV_UNREGISTER has already\nunlisted the device from the ifindex table, that lookup fails and\ncan_rx_unregister() is silently skipped, leaving a stale CAN filter\npointing at the soon-to-be-freed bcm_op/socket.\n\nHold a netdev_hold()/netdev_put() tracked reference on op-\u003erx_reg_dev\nfrom the moment the rx filter is registered in bcm_rx_setup() until it\nis unregistered in bcm_rx_unreg(), and use that reference directly in\nbcm_release() and bcm_delete_rx_op() instead of re-looking the device\nup by ifindex.",
"id": "GHSA-q526-m4v6-prwf",
"modified": "2026-08-19T18:32:27Z",
"published": "2026-08-15T06:32:12Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72113"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/04d23061bbf18d5d81022eb21e9d32e99d24468d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/633bda66fbf309f5de5e1ad6defe8e6b1d77a20f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/84aa4807816e405c1bf87114fc63e06d244281ef"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b024c21c9066f6957b7d4a8f2037e4b000c5e041"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/bd5232663524e94cc5aad861dca11e3db8e2ab6f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d59948293ea34b6337ce2b5febab8510de70048c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/dcaee869913c7210cd47ed0a8f27349d7bdcdb7b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ee8b36d0faca08f35b889b6e9aa850695e5b8ba9"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
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Nomenclature
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