CVE-2026-53399

CVE CVE-2026-53399EUVD EUVD-2026-45454Published 2026-07-19T12:02:00.000ZLast changed 2026-08-05T12:35:38.000ZCVSS 9.8

What the advisory describes

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).

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

• Linux — Linux patch: 7.1.3; c5c707f96fc9a6e5a57ca5baac892673270abe3d <83c2b7797742339bb768f83935f7ca33950db138; c5c707f96fc9a6e5a57ca5baac892673270abe3d <2e0a5d6d62600b8c614d1b55e50ef94035d6adf9; c5c707f96fc9a6e5a57ca5baac892673270abe3d <8dee7c278f1c2b5bb80e17a6281c3812fc8b0cdd; c5c707f96fc9a6e5a57ca5baac892673270abe3d <d369e5edfaaf83a448016e2f1da392b2174be801; c5c707f96fc9a6e5a57ca5baac892673270abe3d <d788ef40a7517d22c97ab01700e4ae4c611b6f2f; patch: 6.18.39; patch: 6.1.178; patch: 5.10.261; c5c707f96fc9a6e5a57ca5baac892673270abe3d <7bbb7ce74051c8be4b69ff44ce3db370600dae61; patch: 6.6.145; patch: 0; patch: 5.15.212; c5c707f96fc9a6e5a57ca5baac892673270abe3d <30d55c8aabb261bc3f427d6b9aae7ef6206063f9; patch: 6.12.96; c5c707f96fc9a6e5a57ca5baac892673270abe3d <48a586e382e4db1dbf958d44b63e081df5f8ed04; patch: 7.2-rc1; 4.0

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

• Linux — Linux

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