net/packet: avoid fanout hook re-registration after unregister
In the Linux kernel, the following vulnerability has been resolved: net/packet: avoid fanout hook re-registration after unregister packet_set_ring() temporarily detaches a socket from packet delivery while reconfiguring its ring. It records the previous running state, clears po->num, unregisters the protocol hook when needed, drops po->bind_lock, and later restores po->num and re-registers the hook from the saved was_running value. That unlocked window can race with NETDEV_UNREGISTER. The notifier can observe the socket as not running, skip __unregister_prot_hook(), and invalidate the per-socket binding by setting po->ifindex to -1 and clearing po->prot_hook.dev. A one-member fanout group can still retain its shared fanout hook device pointer. When packet_set_ring() resumes, re-registering solely from the stale was_running state can re-add the fanout hook after the device has been unregistered. Treat po->ifindex == -1 as an invalidated binding after reacquiring po->bind_lock. This is distinct from ifindex 0, the normal unbound/wildcard state: ifindex -1 marks an existing device binding that was invalidated when the device was unregistered. Restore po->num as before, but do not re-register the hook if device unregister already detached the socket.
CVE-2026-68338
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-68338
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc",
"lessThan": "acb40ebfa5c4d62f84339fcbf713f2a9fd033a71",
"versionType": "git"
},
{
"status": "affected",
"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc",
"lessThan": "c820f4b7f2fa38f8769db0d0cefdd94e2721504d",
"versionType": "git"
},
{
"status": "affected",
"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc",
"lessThan": "4628efbdc7affd094181f5263e65c1062e31f15f",
"versionType": "git"
},
{
"status": "affected",
"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc",
"lessThan": "80ec024d53a05c60ad1d08968dcf745f10c1665c",
"versionType": "git"
},
{
"status": "affected",
"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc",
"lessThan": "0a052e0808e015e68144a9877e6ef42b952c49fa",
"versionType": "git"
},
{
"status": "affected",
"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc",
"lessThan": "1bc55c29cd85818e9052f17deb287d5a11fb817f",
"versionType": "git"
},
{
"status": "affected",
"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc",
"lessThan": "a885387dae7986a55bae5c77a15bdd447f64e9b9",
"versionType": "git"
},
{
"status": "affected",
"version": "dc99f600698dcac69b8f56dda9a8a00d645c5ffc",
"lessThan": "50aff80475abd3533eef4320477037e6fcc6b56e",
"versionType": "git"
}
],
"programFiles": [
"net/packet/af_packet.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.1"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.1",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.265",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.216",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.183",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.148",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.101",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.42",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.6",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/packet/af_packet.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-68338
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #41699 · Revision 1
- Added to Heist Feed
- Publisher date