ghsa-5mxp-4f79-c8g9
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
netmem: prevent TX of unreadable skbs
Currently on stable trees we have support for netmem/devmem RX but not TX. It is not safe to forward/redirect an RX unreadable netmem packet into the device's TX path, as the device may call dma-mapping APIs on dma addrs that should not be passed to it.
Fix this by preventing the xmit of unreadable skbs.
Tested by configuring tc redirect:
sudo tc qdisc add dev eth1 ingress sudo tc filter add dev eth1 ingress protocol ip prio 1 flower ip_proto \ tcp src_ip 192.168.1.12 action mirred egress redirect dev eth1
Before, I see unreadable skbs in the driver's TX path passed to dma mapping APIs.
After, I don't see unreadable skbs in the driver's TX path passed to dma mapping APIs.
{
"affected": [],
"aliases": [
"CVE-2025-21954"
],
"database_specific": {
"cwe_ids": [
"CWE-401"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-04-01T16:15:26Z",
"severity": "MODERATE"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetmem: prevent TX of unreadable skbs\n\nCurrently on stable trees we have support for netmem/devmem RX but not\nTX. It is not safe to forward/redirect an RX unreadable netmem packet\ninto the device\u0027s TX path, as the device may call dma-mapping APIs on\ndma addrs that should not be passed to it.\n\nFix this by preventing the xmit of unreadable skbs.\n\nTested by configuring tc redirect:\n\nsudo tc qdisc add dev eth1 ingress\nsudo tc filter add dev eth1 ingress protocol ip prio 1 flower ip_proto \\\n\ttcp src_ip 192.168.1.12 action mirred egress redirect dev eth1\n\nBefore, I see unreadable skbs in the driver\u0027s TX path passed to dma\nmapping APIs.\n\nAfter, I don\u0027t see unreadable skbs in the driver\u0027s TX path passed to dma\nmapping APIs.",
"id": "GHSA-5mxp-4f79-c8g9",
"modified": "2025-10-31T18:31:11Z",
"published": "2025-04-01T18:30:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-21954"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1c17c8ced25c5fbe424c7ad7ea11d33014a986b1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/454825019d2f0c59e5174ece9e713f45ad80beff"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f3600c867c99a2cc8038680ecf211089c50e7971"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
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- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.