Description
In the Linux kernel, the following vulnerability has been resolved:
sunrpc: defer rq_argp and rq_resp free until after RCU grace period
svc_rqst_free() frees rqstp->rq_argp and rqstp->rq_resp synchronously via kfree(), but defers the rqstp struct free via kfree_rcu(). After svc_exit_thread() calls list_del_rcu() and svc_rqst_free(), there is a window where RCU readers that started before list_del_rcu() can still traverse the thread list and find the rqstp. These readers (e.g. nfsd_nl_rpc_status_get_dumpit()) dereference rqstp->rq_argp, which has already been freed — a use-after-free.
Fix this by moving the kfree of rq_argp and rq_resp into an explicit call_rcu() callback alongside the struct free. Resources not accessed by RCU readers (bvec, buffer pages, scratch folio, auth_data) remain synchronously freed.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HAffected software
Source: the vendor's advisory (CNA). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 812443865c5fc255363d4a684a62c086af1addca, < c977158237bccc3d2512d5b17c47ee3760dc8839; >= 812443865c5fc255363d4a684a62c086af1addca, < 0ea49d69aa806008b2424c8cf21cf746b9963967; >= 812443865c5fc255363d4a684a62c086af1addca, < 08bc49e0541260bf294962cf889a32a2d2713ad6; >= 812443865c5fc255363d4a684a62c086af1addca, < e0c5693d3f9a5d4911735ab0e0eba4eecb1f1090; >= 812443865c5fc255363d4a684a62c086af1addca, < c479bde671cbe2f9e152834a8b0eb7c3c295bbaf |
| Linux | Linux | 3.19 |
References
- https://git.kernel.org/stable/c/08bc49e0541260bf294962cf889a32a2d2713ad6
- https://git.kernel.org/stable/c/0ea49d69aa806008b2424c8cf21cf746b9963967
- https://git.kernel.org/stable/c/c479bde671cbe2f9e152834a8b0eb7c3c295bbaf
- https://git.kernel.org/stable/c/c977158237bccc3d2512d5b17c47ee3760dc8839
- https://git.kernel.org/stable/c/e0c5693d3f9a5d4911735ab0e0eba4eecb1f1090
Timeline
- Published
- Sep 11, 2026
- Last modified
- Oct 30, 2026
- NVD status
- Received