CVE-2023-54269: Linux

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: double free xprt_ctxt while still in use When an RPC request is deferred, the rq_xprt_ctxt pointer is moved out of the svc_rqst into the svc_deferred_req. When the deferred request is revisited, the pointer is copied into the new svc_rqst - and also remains in the svc_deferred_req. In the (rare?) case that the request is deferred a second time, the old svc_deferred_req is reused - it still has all the correct content. However in that case the rq_xprt_ctxt pointer is NOT cleared so that when xpo_release_xprt is called, the ctxt is freed (UDP) or possible added to a free list (RDMA). When the deferred request is revisited for a second time, it will reference this ctxt which may be invalid, and the free the object a second time which is likely to oops. So change svc_defer() to *always* clear rq_xprt_ctxt, and assert that the value is now stored in the svc_deferred_req.

Affected products

• Linux Linux: from 5.15.35, before 5.15.113 (fixed in 5.15.113); from 5.17.4, before 5.18 (fixed in 5.18); from 5.18, before 6.1.30 (fixed in 6.1.30); from 6.2, before 6.3.4 (fixed in 6.3.4)

Published 2025-12-30. Last modified 2026-08-04.