| Message ID | 20210510095649.3302835-1-andy.shevchenko@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v1,1/1] iio: dac: ad5770r: Put fwnode in error case during ->probe() | expand |
On Mon, May 10, 2021 at 12:59 PM Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > > device_for_each_child_node() bumps a reference counting of a returned variable. > We have to balance it whenever we return to the caller. This feels like the device_for_each_child_node() [and the of_node variant] iterator[s] need[s] some re-design to account for how easy it is to slip stuff by. But that's something quite out of this scope. Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com> > > Fixes: cbbb819837f6 ("iio: dac: ad5770r: Add AD5770R support") > Cc: Alexandru Tachici <alexandru.tachici@analog.com> > Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com> > --- > drivers/iio/dac/ad5770r.c | 16 +++++++++++----- > 1 file changed, 11 insertions(+), 5 deletions(-) > > diff --git a/drivers/iio/dac/ad5770r.c b/drivers/iio/dac/ad5770r.c > index 7ab2ccf90863..8107f7bbbe3c 100644 > --- a/drivers/iio/dac/ad5770r.c > +++ b/drivers/iio/dac/ad5770r.c > @@ -524,23 +524,29 @@ static int ad5770r_channel_config(struct ad5770r_state *st) > device_for_each_child_node(&st->spi->dev, child) { > ret = fwnode_property_read_u32(child, "num", &num); > if (ret) > - return ret; > - if (num >= AD5770R_MAX_CHANNELS) > - return -EINVAL; > + goto err_child_out; > + if (num >= AD5770R_MAX_CHANNELS) { > + ret = -EINVAL; > + goto err_child_out; > + } > > ret = fwnode_property_read_u32_array(child, > "adi,range-microamp", > tmp, 2); > if (ret) > - return ret; > + goto err_child_out; > > min = tmp[0] / 1000; > max = tmp[1] / 1000; > ret = ad5770r_store_output_range(st, min, max, num); > if (ret) > - return ret; > + goto err_child_out; > } > > + return 0; > + > +err_child_out: > + fwnode_handle_put(child); > return ret; > } > > -- > 2.31.1 >
On Thu, 13 May 2021 01:00:22 +0300 Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > On Wednesday, May 12, 2021, Alexandru Ardelean <ardeleanalex@gmail.com> > wrote: > > > On Mon, May 10, 2021 at 12:59 PM Andy Shevchenko > > <andy.shevchenko@gmail.com> wrote: > > > > > > device_for_each_child_node() bumps a reference counting of a returned > > variable. > > > We have to balance it whenever we return to the caller. > > > > This feels like the device_for_each_child_node() [and the of_node > > variant] iterator[s] need[s] some re-design to account for how easy it > > is to slip stuff by. > > > I don’t know how you can do it differently if you wish to give a guarantee > that object doesn’t suddenly disappear while you are iterating over it. > > Look at the bus_find_device() and similar APIs, they basically do the > similar. > > > > > But that's something quite out of this scope. > > > > Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com> > > > > > Thanks. > Applied to the fixes-togreg branch of iio.git and marked for stable. Thanks, Joathan > > > > > > > Fixes: cbbb819837f6 ("iio: dac: ad5770r: Add AD5770R support") > > > Cc: Alexandru Tachici <alexandru.tachici@analog.com> > > > Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com> > > > --- > > > drivers/iio/dac/ad5770r.c | 16 +++++++++++----- > > > 1 file changed, 11 insertions(+), 5 deletions(-) > > > > > > diff --git a/drivers/iio/dac/ad5770r.c b/drivers/iio/dac/ad5770r.c > > > index 7ab2ccf90863..8107f7bbbe3c 100644 > > > --- a/drivers/iio/dac/ad5770r.c > > > +++ b/drivers/iio/dac/ad5770r.c > > > @@ -524,23 +524,29 @@ static int ad5770r_channel_config(struct > > ad5770r_state *st) > > > device_for_each_child_node(&st->spi->dev, child) { > > > ret = fwnode_property_read_u32(child, "num", &num); > > > if (ret) > > > - return ret; > > > - if (num >= AD5770R_MAX_CHANNELS) > > > - return -EINVAL; > > > + goto err_child_out; > > > + if (num >= AD5770R_MAX_CHANNELS) { > > > + ret = -EINVAL; > > > + goto err_child_out; > > > + } > > > > > > ret = fwnode_property_read_u32_array(child, > > > > > "adi,range-microamp", > > > tmp, 2); > > > if (ret) > > > - return ret; > > > + goto err_child_out; > > > > > > min = tmp[0] / 1000; > > > max = tmp[1] / 1000; > > > ret = ad5770r_store_output_range(st, min, max, num); > > > if (ret) > > > - return ret; > > > + goto err_child_out; > > > } > > > > > > + return 0; > > > + > > > +err_child_out: > > > + fwnode_handle_put(child); > > > return ret; > > > } > > > > > > -- > > > 2.31.1 > > > > > > >
diff --git a/drivers/iio/dac/ad5770r.c b/drivers/iio/dac/ad5770r.c index 7ab2ccf90863..8107f7bbbe3c 100644 --- a/drivers/iio/dac/ad5770r.c +++ b/drivers/iio/dac/ad5770r.c @@ -524,23 +524,29 @@ static int ad5770r_channel_config(struct ad5770r_state *st) device_for_each_child_node(&st->spi->dev, child) { ret = fwnode_property_read_u32(child, "num", &num); if (ret) - return ret; - if (num >= AD5770R_MAX_CHANNELS) - return -EINVAL; + goto err_child_out; + if (num >= AD5770R_MAX_CHANNELS) { + ret = -EINVAL; + goto err_child_out; + } ret = fwnode_property_read_u32_array(child, "adi,range-microamp", tmp, 2); if (ret) - return ret; + goto err_child_out; min = tmp[0] / 1000; max = tmp[1] / 1000; ret = ad5770r_store_output_range(st, min, max, num); if (ret) - return ret; + goto err_child_out; } + return 0; + +err_child_out: + fwnode_handle_put(child); return ret; }
device_for_each_child_node() bumps a reference counting of a returned variable. We have to balance it whenever we return to the caller. Fixes: cbbb819837f6 ("iio: dac: ad5770r: Add AD5770R support") Cc: Alexandru Tachici <alexandru.tachici@analog.com> Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com> --- drivers/iio/dac/ad5770r.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-)