If ret ends up negative, mutex_unlock is called repeatedly in an infinite
loop, which of course is pretty nasty...
Issue found by smatch:
drivers/iio/inkern.c:751 iio_read_avail_channel_raw() error: double unlock
'mutex:&chan->indio_dev->info_exist_lock'
Fixes: 00c5f80c2fad ("iio: inkern: add helpers to query available values from
channels")
Signed-off-by: Peter Rosin <p...@axentia.se>
---
drivers/iio/inkern.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
v1 -> v2 changes:
- Be clear about that there is a real nasty issue and that it isn't only
about avoiding some insignificant static checker issue.
v1: https://lkml.org/lkml/2017/4/20/887
Cheers,
peda
diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index 7a13535dc3e9..a3941bade6a7 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -750,11 +750,9 @@ int iio_read_avail_channel_raw(struct iio_channel *chan,
err_unlock:
mutex_unlock(&chan->indio_dev->info_exist_lock);
- if (ret >= 0 && type != IIO_VAL_INT) {
+ if (ret >= 0 && type != IIO_VAL_INT)
/* raw values are assumed to be IIO_VAL_INT */
ret = -EINVAL;
- goto err_unlock;
- }
return ret;
}
--
2.1.4
