From: Pei Xiao Date: Wed, 29 Oct 2025 02:40:16 +0000 (+0800) Subject: iio: adc: at91-sama5d2_adc: Fix potential use-after-free in sama5d2_adc driver X-Git-Tag: v6.6.122~66 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9795fe80976f8c31cafda7d44edfc0f532d1f7c4;p=thirdparty%2Fkernel%2Fstable.git iio: adc: at91-sama5d2_adc: Fix potential use-after-free in sama5d2_adc driver commit dbdb442218cd9d613adeab31a88ac973f22c4873 upstream. at91_adc_interrupt can call at91_adc_touch_data_handler function to start the work by schedule_work(&st->touch_st.workq). If we remove the module which will call at91_adc_remove to make cleanup, it will free indio_dev through iio_device_unregister but quite a bit later. While the work mentioned above will be used. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | at91_adc_workq_handler at91_adc_remove | iio_device_unregister(indio_dev) | //free indio_dev a bit later | | iio_push_to_buffers(indio_dev) | //use indio_dev Fix it by ensuring that the work is canceled before proceeding with the cleanup in at91_adc_remove. Fixes: 23ec2774f1cc ("iio: adc: at91-sama5d2_adc: add support for position and pressure channels") Signed-off-by: Pei Xiao Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c index b54e4481fafb..4ca39a2527c2 100644 --- a/drivers/iio/adc/at91-sama5d2_adc.c +++ b/drivers/iio/adc/at91-sama5d2_adc.c @@ -2504,6 +2504,7 @@ static int at91_adc_remove(struct platform_device *pdev) struct at91_adc_state *st = iio_priv(indio_dev); iio_device_unregister(indio_dev); + cancel_work_sync(&st->touch_st.workq); at91_adc_dma_disable(st);