The DPIO interrupt handler accesses priv->io, but dpaa2_dpio_remove() releases that object before tearing down the interrupts. The IRQ was requested with devm_request_irq(), and unregister_dpio_irq_handlers() only clears its affinity hint. fsl_mc_free_irqs() returns IRQ resources to the MC resource pool without freeing the handler. An interrupt can therefore access the freed I/O object before devres releases the IRQ. Explicitly free the managed IRQ in unregister_dpio_irq_handlers() before returning its resource to the pool, and perform IRQ teardown before releasing the I/O object. This also waits for an in-flight handler while the object is still valid. This issue was identified during our ongoing static-analysis research while reviewing kernel code. Fixes: 993fec7e11ca ("bus: fsl-mc: dpio: add the DPAA2 DPIO object driver") Cc: stable@vger.kernel.org Assisted-by: LLM Co-developed-by: Ijae Kim Signed-off-by: Ijae Kim Signed-off-by: Myeonghun Pak --- Changes in v2: - Move devm_free_irq() into unregister_dpio_irq_handlers(), as suggested by Ioana Ciornei, to keep IRQ registration and unregistration in sync. - Base this patch on the probe cleanup fix in patch 1, which removes the unregister call from the probe error path. - Add Cc: stable@vger.kernel.org. drivers/soc/fsl/dpio/dpio-driver.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/soc/fsl/dpio/dpio-driver.c b/drivers/soc/fsl/dpio/dpio-driver.c index 8d31346..d8f28fb 100644 --- a/drivers/soc/fsl/dpio/dpio-driver.c +++ b/drivers/soc/fsl/dpio/dpio-driver.c @@ -88,6 +88,7 @@ static void unregister_dpio_irq_handlers(struct fsl_mc_device *dpio_dev) /* clear the affinity hint */ irq_set_affinity_hint(irq->virq, NULL); + devm_free_irq(&dpio_dev->dev, irq->virq, &dpio_dev->dev); } static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu) @@ -276,10 +277,10 @@ static void dpaa2_dpio_remove(struct fsl_mc_device *dpio_dev) priv = dev_get_drvdata(dev); cpu = dpaa2_io_get_cpu(priv->io); - dpaa2_io_down(priv->io); - dpio_teardown_irqs(dpio_dev); + dpaa2_io_down(priv->io); + cpumask_set_cpu(cpu, cpus_unused_mask); err = dpio_open(dpio_dev->mc_io, 0, dpio_dev->obj_desc.id, -- 2.53.0