From 1ca44751915134f19e8627768159781e75b5da50 Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Thu, 18 Jun 2026 11:09:08 +0100 Subject: [PATCH] comedi: aio_iiro_16: Add sanity check to interrupt handler The driver requests an interrupt handler for the device, after setting device registers to disable interrupt generation. The interrupt handler should not be called prematurely unless the user-configured I/O port base address and/or IRQ number are incorrect or the hardware is bad. For safety, check the dev->attached flag in the interrupt handler to ensure the device has been fully set up, avoiding a possible null pointer dereference of dev->read_subdev. Reported-by: Jaeyoung Chung Link: https://lore.kernel.org/lkml/20260610115912.780131-1-jjy600901@snu.ac.kr/ Reported-by: Sangyun Kim Reported-by: Kyungwook Boo Signed-off-by: Ian Abbott Link: https://patch.msgid.link/20260618102949.26607-2-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman --- drivers/comedi/drivers/aio_iiro_16.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/comedi/drivers/aio_iiro_16.c b/drivers/comedi/drivers/aio_iiro_16.c index d5d18fa2c638..52385b14a9a4 100644 --- a/drivers/comedi/drivers/aio_iiro_16.c +++ b/drivers/comedi/drivers/aio_iiro_16.c @@ -59,6 +59,9 @@ static irqreturn_t aio_iiro_16_cos(int irq, void *d) unsigned int status; unsigned int val; + if (!dev->attached) + return IRQ_NONE; + status = inb(dev->iobase + AIO_IIRO_16_STATUS); if (!(status & AIO_IIRO_16_STATUS_IRQE)) return IRQ_NONE;