ghsa-8q2m-46mc-pjw4
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
net: bridge: fix vlan tunnel dst null pointer dereference
This patch fixes a tunnel_dst null pointer dereference due to lockless access in the tunnel egress path. When deleting a vlan tunnel the tunnel_dst pointer is set to NULL without waiting a grace period (i.e. while it's still usable) and packets egressing are dereferencing it without checking. Use READ/WRITE_ONCE to annotate the lockless use of tunnel_id, use RCU for accessing tunnel_dst and make sure it is read only once and checked in the egress path. The dst is already properly RCU protected so we don't need to do anything fancy than to make sure tunnel_id and tunnel_dst are read only once and checked in the egress path.
{
"affected": [],
"aliases": [
"CVE-2021-47223"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-21T15:15:11Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: fix vlan tunnel dst null pointer dereference\n\nThis patch fixes a tunnel_dst null pointer dereference due to lockless\naccess in the tunnel egress path. When deleting a vlan tunnel the\ntunnel_dst pointer is set to NULL without waiting a grace period (i.e.\nwhile it\u0027s still usable) and packets egressing are dereferencing it\nwithout checking. Use READ/WRITE_ONCE to annotate the lockless use of\ntunnel_id, use RCU for accessing tunnel_dst and make sure it is read\nonly once and checked in the egress path. The dst is already properly RCU\nprotected so we don\u0027t need to do anything fancy than to make sure\ntunnel_id and tunnel_dst are read only once and checked in the egress path.",
"id": "GHSA-8q2m-46mc-pjw4",
"modified": "2024-05-21T15:31:39Z",
"published": "2024-05-21T15:31:39Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47223"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/24a6e55f17aa123bc1fc54b7d3c410b41bc16530"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/58e2071742e38f29f051b709a5cca014ba51166f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a2241e62f6b4a774d8a92048fdf59c45f6c2fe5c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/abb02e05cb1c0a30dd873a29f33bc092067dc35d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ad7feefe7164892db424c45687472db803d87f79"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fe0448a3fad365a747283a00a1d1ad5e8d6675b7"
}
],
"schema_version": "1.4.0",
"severity": []
}