ghsa-j4rg-4m7w-4hr3
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
vsock: Ignore signal/timeout on connect() if already established
During connect(), acting on a signal/timeout by disconnecting an already established socket leads to several issues:
-
connect() invoking vsock_transport_cancel_pkt() -> virtio_transport_purge_skbs() may race with sendmsg() invoking virtio_transport_get_credit(). This results in a permanently elevated
vvs->bytes_unsent. Which, in turn, confuses the SOCK_LINGER handling. -
connect() resetting a connected socket's state may race with socket being placed in a sockmap. A disconnected socket remaining in a sockmap breaks sockmap's assumptions. And gives rise to WARNs.
-
connect() transitioning SS_CONNECTED -> SS_UNCONNECTED allows for a transport change/drop after TCP_ESTABLISHED. Which poses a problem for any simultaneous sendmsg() or connect() and may result in a use-after-free/null-ptr-deref.
Do not disconnect socket on signal/timeout. Keep the logic for unconnected sockets: they don't linger, can't be placed in a sockmap, are rejected by sendmsg().
{
"affected": [],
"aliases": [
"CVE-2025-40248"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-04T16:16:18Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock: Ignore signal/timeout on connect() if already established\n\nDuring connect(), acting on a signal/timeout by disconnecting an already\nestablished socket leads to several issues:\n\n1. connect() invoking vsock_transport_cancel_pkt() -\u003e\n virtio_transport_purge_skbs() may race with sendmsg() invoking\n virtio_transport_get_credit(). This results in a permanently elevated\n `vvs-\u003ebytes_unsent`. Which, in turn, confuses the SOCK_LINGER handling.\n\n2. connect() resetting a connected socket\u0027s state may race with socket\n being placed in a sockmap. A disconnected socket remaining in a sockmap\n breaks sockmap\u0027s assumptions. And gives rise to WARNs.\n\n3. connect() transitioning SS_CONNECTED -\u003e SS_UNCONNECTED allows for a\n transport change/drop after TCP_ESTABLISHED. Which poses a problem for\n any simultaneous sendmsg() or connect() and may result in a\n use-after-free/null-ptr-deref.\n\nDo not disconnect socket on signal/timeout. Keep the logic for unconnected\nsockets: they don\u0027t linger, can\u0027t be placed in a sockmap, are rejected by\nsendmsg().\n\n[1]: https://lore.kernel.org/netdev/e07fd95c-9a38-4eea-9638-133e38c2ec9b@rbox.co/\n[2]: https://lore.kernel.org/netdev/20250317-vsock-trans-signal-race-v4-0-fc8837f3f1d4@rbox.co/\n[3]: https://lore.kernel.org/netdev/60f1b7db-3099-4f6a-875e-af9f6ef194f6@rbox.co/",
"id": "GHSA-j4rg-4m7w-4hr3",
"modified": "2025-12-07T00:30:56Z",
"published": "2025-12-04T18:30:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-40248"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/002541ef650b742a198e4be363881439bb9d86b4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3f71753935d648082a8279a97d30efe6b85be680"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5998da5a8208ae9ad7838ba322bccb2bdcd95e81"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/67432915145848658149683101104e32f9fd6559"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ab6b19f690d89ae4709fba73a3c4a7911f495b7a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/da664101fb4a0de5cb70d2bae6a650df954df2af"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/eeca93f06df89be5a36305b7b9dae1ed65550dfc"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f1c170cae285e4b8f61be043bb17addc3d0a14b5"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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