In the Linux kernel, the following vulnerability has been resolved:
nfsd: release layout stid on setlease failure
nfs4_alloc_stid() publishes the new stid into cl->cl_stateids via
idr_alloc_cyclic() under cl_lock before returning to
nfsd4_alloc_layout_stateid(). When nfsd4_layout_setlease() then
fails, the error path frees the layout stateid directly with
kmem_cache_free() without ever calling idr_remove(), leaving the
IDR slot pointing at freed slab memory. Any subsequent IDR walker
(states_show, client teardown) dereferences the dangling pointer.
The correct teardown for an IDR-published stid is nfs4_put_stid(),
which removes the IDR slot under cl_lock, dispatches sc_free
(nfsd4_free_layout_stateid) to release ls->ls_file via
nfsd4_close_layout(), and drops the nfs4_file reference in its
tail.
A second issue blocks that switch: nfsd4_free_layout_stateid()
unconditionally inspects ls->ls_fence_work via
delayed_work_pending() under ls_lock, but
INIT_DELAYED_WORK(&ls->ls_fence_work, ...) currently runs only
after the setlease call. On the setlease-failure path the
destructor would touch an uninitialized delayed_work.
nfsd4_alloc_layout_stateid()
nfs4_alloc_stid() /* idr_alloc_cyclic under cl_lock */
nfsd4_layout_setlease() /* fails */
nfs4_put_stid()
nfsd4_free_layout_stateid()
delayed_work_pending(&ls->ls_fence_work) /* needs INIT */
nfsd4_close_layout() /* nfsd_file_put(ls->ls_file) */
put_nfs4_file()
Fix by hoisting the ls_fenced / ls_fence_delay / INIT_DELAYED_WORK
initialization above the nfsd4_layout_setlease() call, and replace
the manual nfsd_file_put + put_nfs4_file + kmem_cache_free cleanup
with a single nfs4_put_stid(stp).
References
Configurations
Configuration 1 (hide)
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History
29 Jul 2026, 20:31
| Type | Values Removed | Values Added |
|---|---|---|
| CWE | CWE-476 | |
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| First Time |
Linux linux Kernel
Linux |
|
| References | () https://git.kernel.org/stable/c/2e0a5d6d62600b8c614d1b55e50ef94035d6adf9 - Patch | |
| References | () https://git.kernel.org/stable/c/30d55c8aabb261bc3f427d6b9aae7ef6206063f9 - Patch | |
| References | () https://git.kernel.org/stable/c/48a586e382e4db1dbf958d44b63e081df5f8ed04 - Patch | |
| References | () https://git.kernel.org/stable/c/7bbb7ce74051c8be4b69ff44ce3db370600dae61 - Patch | |
| References | () https://git.kernel.org/stable/c/83c2b7797742339bb768f83935f7ca33950db138 - Patch | |
| References | () https://git.kernel.org/stable/c/8dee7c278f1c2b5bb80e17a6281c3812fc8b0cdd - Patch | |
| References | () https://git.kernel.org/stable/c/d369e5edfaaf83a448016e2f1da392b2174be801 - Patch | |
| References | () https://git.kernel.org/stable/c/d788ef40a7517d22c97ab01700e4ae4c611b6f2f - Patch |
24 Jul 2026, 15:18
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
20 Jul 2026, 15:16
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 9.8 |
19 Jul 2026, 12:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-07-19 12:16
Updated : 2026-07-29 20:31
NVD link : CVE-2026-53399
Mitre link : CVE-2026-53399
CVE.ORG link : CVE-2026-53399
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-476
NULL Pointer Dereference
