patch "iio: dac: ad5686: fix input raw value check" added to char-misc-linus

patch "iio: dac: ad5686: fix input raw value check" added to char-misc-linus

[gregkh]

This is a note to let you know that I've just added the patch titled

    iio: dac: ad5686: fix input raw value check

to my char-misc git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


From d01220ee5e43c65a206df827b39bf5cf5f7b9dce Mon Sep 17 00:00:00 2001
From: Rodrigo Alencar <rodrigo.alencar@analog.com>
Date: Fri, 1 May 2026 10:14:55 +0100
Subject: iio: dac: ad5686: fix input raw value check

Fix range check for input raw value, which is off by one, i.e., for a
10-bit DAC the max valid value is 1023, but 1 << 10 equals 1024, which
passes the previous check, allowing an out-of-range write. The issue
exists since the ad5686 driver was first introduced.

Fixes: c2f37c8dcadc ("iio: dac: New driver for AD5686R, AD5685R, AD5684R Digital to analog converters")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Rodrigo Alencar <rodrigo.alencar@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/dac/ad5686.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
index b85d5c5a864b..27878a6318ff 100644
--- a/drivers/iio/dac/ad5686.c
+++ b/drivers/iio/dac/ad5686.c
@@ -154,7 +154,7 @@ static int ad5686_write_raw(struct iio_dev *indio_dev,
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		if (val > (1 << chan->scan_type.realbits) || val < 0)
+		if (val >= (1 << chan->scan_type.realbits) || val < 0)
 			return -EINVAL;
 
 		mutex_lock(&st->lock);
-- 
2.54.0