From 13f4796223489a5349b466ce54bb868f46c9fefd Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Thu, 18 Jun 2026 11:09:12 +0100 Subject: [PATCH] comedi: ni_atmio16d: 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/20260618102949.26607-6-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman --- drivers/comedi/drivers/ni_atmio16d.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/comedi/drivers/ni_atmio16d.c b/drivers/comedi/drivers/ni_atmio16d.c index b2772d909896..6765cdc276ca 100644 --- a/drivers/comedi/drivers/ni_atmio16d.c +++ b/drivers/comedi/drivers/ni_atmio16d.c @@ -223,6 +223,9 @@ static irqreturn_t atmio16d_interrupt(int irq, void *d) struct comedi_subdevice *s = dev->read_subdev; unsigned short val; + if (!dev->attached) + return IRQ_NONE; + val = inw(dev->iobase + AD_FIFO_REG); comedi_buf_write_samples(s, &val, 1); comedi_handle_events(dev, s);