CVE-2026-93224
Received
Received - Intake
Memory Leak in Linux Kernel svcrdma Module
Vulnerability report for CVE-2026-93224, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-24
Last updated on: 2026-09-25
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
svcrdma: Fix unmatched rn_unregister on failed accept
When svc_rdma_accept() takes the errout path before
rpcrdma_rn_register() has succeeded, the existing cleanup block
calls rpcrdma_rn_unregister(dev, &newxprt->sc_rn) unconditionally.
svcxprt_rdma is kzalloc'd, so on that path sc_rn.rn_index is 0 and
sc_rn.rn_done is NULL; the unregister therefore xa_erase()s another
caller's slot 0 and performs an unmatched kref_put() on the
rpcrdma_device's rd_kref.
The same errout also brackets the cleanup with svc_xprt_get()/
svc_xprt_put() around the kref_init() birth reference. The kref
goes 1 -> 2 -> 1 and never reaches 0, so the svcxprt_rdma (and the
net/ns_tracker it pinned) is leaked on every failed accept.
rpcrdma_rn_register() writes rn->rn_done last, only after xa_alloc()
and kref_get() have both succeeded, so rn_done == NULL is a natural
"never registered" sentinel. Guard rpcrdma_rn_unregister() with an
early return when rn_done is NULL, and clear rn_done before the
matching xa_erase() so a repeated unregister is also a no-op.
With that guard in place, the accept errout drops the kref_init()
birth reference via svc_xprt_put(), which dispatches svc_rdma_free().
Teardown of sc_qp, sc_sq_cq, sc_rq_cq, and sc_pd runs under existing
IS_ERR/NULL guards in svc_rdma_free(); sc_rn is covered by the new
rn_done sentinel; sc_cm_id is non-NULL on every errout path because
svc_rdma_accept() dereferences it above the first goto errout.
svc_xprt_free() drops the module reference associated with the freed
transport, and svc_handle_xprt() drops its pre-acquired reference
when ->xpo_accept() returns NULL. Take a replacement module reference
before svc_xprt_put() so the two module_put()s remain balanced.
The rn_done guard also covers svc_rdma_free()'s non-listener call
to rpcrdma_rn_unregister() for transports whose register attempt
failed or never ran.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
