CVE-2026-97603

Status: UPDATED  |  Advisory ID: CVE-2026-97603

Key Details

Affected Products, Subsystems & Sectors

What to Know

In the Linux kernel, the following vulnerability has been resolved:

idpf: disable DIM work before freeing q_vectors

idpf never drains the Tx/Rx DIM works before freeing the memory they

live in. tx_dim and rx_dim are embedded in struct idpf_q_vector, they

are queued from the NAPI poll via net_dim(), and idpf_vport_intr_rel()

ends with kfree(rsrc->q_vectors). Nothing in the driver cancels them.

idpf_tx_dim_work() and idpf_rx_dim_work() then run on freed memory:

idpf_vport_intr_write_itr() writes the ITR register through

q_vector->intr_reg.tx_itr / rx_itr, void __iomem pointers loaded out of

the freed q_vector. No configuration is needed to get there --

IDPF_ITR_IS_DYNAMIC() is defined as (itr_mode) and idpf_vport_alloc()

initialises both modes to IDPF_ITR_DYNAMIC.

Draining after idpf_vport_intr_napi_dis_all() is not enough on its own.

idpf_net_dim() is called from inside the

"if (napi_complete_done(napi, work_done))" branch of the poll, and

napi_complete_done() has already cleared NAPIF_STATE_SCHED by then.

napi_disable_locked() waits only while (val & (NAPIF_STATE_SCHED |

NAPIF_STATE_NPSVC)), so napi_disable() can return while the poll tail is

still queueing the work, and a plain cancel_work_sync() would be

re-armed behind the drain.

Use disable_work_sync(): schedule_work() on a work with a non-zero

disable count is dropped by clear_pending_if_disabled() before

__queue_work() is reached.

Move idpf_init_dim() to idpf_vport_intr_alloc() so the works are

initialised on every path that can reach the drain -- the three

"goto intr_deinit" sites between idpf_vport_intr_init() and

idpf_vport_intr_ena() get there without the enable side having run.

Nothing re-enables them: rsrc->q_vectors is freed on every exit from

idpf_vport_open() and on every idpf_vport_stop(), so the count dies with

the object.

It is a race, not a deterministic failure -- net_dim() only schedules

once DIM_NEVENTS events have accumulated and the profile index changes.

A KASAN ifup/ifdown loop under load is the way to see it. (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References