[PATCH 0/2] Make cb a required parameter of buffer-cb
When going through the code of the buffer-cb interface and all it's users, I realized that the stm32_adfsdm driver is calling `iio_channel_get_all_cb()` with NULL for the cb. After going a bit trough the stm drivers, it looks like this is actually intentional. However, it is clear that we have a clear/direct route here for a NULL pointer dereference. This change makes cb a required parameter of the API.
The first patch makes the necessary changes to the stm32_adfsdm driver so that it does not break.
Nuno Sá (1): iio: buffer: Return error if no callback is given
Olivier Moysan (1): ASoC: stm32: dfsdm: add stm32_adfsdm_dummy_cb() callback
drivers/iio/buffer/industrialio-buffer-cb.c | 5 +++++ sound/soc/stm/stm32_adfsdm.c | 12 +++++++++++- 2 files changed, 16 insertions(+), 1 deletion(-)
From: Olivier Moysan olivier.moysan@st.com
Adapt STM32 DFSDM driver to a change in iio_channel_get_all_cb() API. The callback pointer becomes a requested parameter of this API, so add a dummy callback to be given as parameter of this function. However, the stm32_dfsdm_get_buff_cb() API is still used instead, to optimize DMA transfers.
Signed-off-by: Olivier Moysan olivier.moysan@st.com Signed-off-by: Nuno Sá nuno.sa@analog.com --- sound/soc/stm/stm32_adfsdm.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/sound/soc/stm/stm32_adfsdm.c b/sound/soc/stm/stm32_adfsdm.c index ec27c13af04f..fb9df3caba12 100644 --- a/sound/soc/stm/stm32_adfsdm.c +++ b/sound/soc/stm/stm32_adfsdm.c @@ -295,6 +295,16 @@ static int stm32_adfsdm_pcm_new(struct snd_soc_component *component, return 0; }
+static int stm32_adfsdm_dummy_cb(const void *data, void *private) +{ + /* + * This dummmy callback is requested by iio_channel_get_all_cb() API, + * but the stm32_dfsdm_get_buff_cb() API is used instead, to optimize + * DMA transfers. + */ + return 0; +} + static struct snd_soc_component_driver stm32_adfsdm_soc_platform = { .open = stm32_adfsdm_pcm_open, .close = stm32_adfsdm_pcm_close, @@ -337,7 +347,7 @@ static int stm32_adfsdm_probe(struct platform_device *pdev) if (IS_ERR(priv->iio_ch)) return PTR_ERR(priv->iio_ch);
- priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, NULL, NULL); + priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, &stm32_adfsdm_dummy_cb, NULL); if (IS_ERR(priv->iio_cb)) return PTR_ERR(priv->iio_cb);
On Sat, Nov 21, 2020 at 05:14:56PM +0100, Nuno Sá wrote:
From: Olivier Moysan olivier.moysan@st.com
Adapt STM32 DFSDM driver to a change in iio_channel_get_all_cb() API. The callback pointer becomes a requested parameter of this API, so add a dummy callback to be given as parameter of this function. However, the stm32_dfsdm_get_buff_cb() API is still used instead, to optimize DMA transfers.
Acked-by: Mark Brown broonie@kernel.org
Return error in case no callback is provided to `iio_channel_get_all_cb()`. There's no point in setting up a buffer-cb if no callback is provided.
Signed-off-by: Nuno Sá nuno.sa@analog.com --- drivers/iio/buffer/industrialio-buffer-cb.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/iio/buffer/industrialio-buffer-cb.c b/drivers/iio/buffer/industrialio-buffer-cb.c index 47c96f7f4976..4c12b7a94af5 100644 --- a/drivers/iio/buffer/industrialio-buffer-cb.c +++ b/drivers/iio/buffer/industrialio-buffer-cb.c @@ -54,6 +54,11 @@ struct iio_cb_buffer *iio_channel_get_all_cb(struct device *dev, struct iio_cb_buffer *cb_buff; struct iio_channel *chan;
+ if (!cb) { + dev_err(dev, "Invalid arguments: A callback must be provided!\n"); + return ERR_PTR(-EINVAL); + } + cb_buff = kzalloc(sizeof(*cb_buff), GFP_KERNEL); if (cb_buff == NULL) return ERR_PTR(-ENOMEM);
On 11/21/20 5:14 PM, Nuno Sá wrote:
Return error in case no callback is provided to `iio_channel_get_all_cb()`. There's no point in setting up a buffer-cb if no callback is provided.
Signed-off-by: Nuno Sá nuno.sa@analog.com
drivers/iio/buffer/industrialio-buffer-cb.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/iio/buffer/industrialio-buffer-cb.c b/drivers/iio/buffer/industrialio-buffer-cb.c index 47c96f7f4976..4c12b7a94af5 100644 --- a/drivers/iio/buffer/industrialio-buffer-cb.c +++ b/drivers/iio/buffer/industrialio-buffer-cb.c @@ -54,6 +54,11 @@ struct iio_cb_buffer *iio_channel_get_all_cb(struct device *dev, struct iio_cb_buffer *cb_buff; struct iio_channel *chan;
- if (!cb) {
dev_err(dev, "Invalid arguments: A callback must be provided!\n");return ERR_PTR(-EINVAL);- }
- cb_buff = kzalloc(sizeof(*cb_buff), GFP_KERNEL); if (cb_buff == NULL) return ERR_PTR(-ENOMEM);
Reviewed-by: Olivier Moysan olivier.moysan@st.com
Best regards, Olivier
On Sat, 21 Nov 2020 17:14:55 +0100 Nuno Sá nuno.sa@analog.com wrote:
When going through the code of the buffer-cb interface and all it's users, I realized that the stm32_adfsdm driver is calling `iio_channel_get_all_cb()` with NULL for the cb. After going a bit trough the stm drivers, it looks like this is actually intentional. However, it is clear that we have a clear/direct route here for a NULL pointer dereference. This change makes cb a required parameter of the API.
The first patch makes the necessary changes to the stm32_adfsdm driver so that it does not break.
Looks good to me. Will leave it a bit longer to let ASOC people take a quick look at it. Give me a poke in a few weeks if it seems like I might have lost it!
Thanks,
Jonathan
Nuno Sá (1): iio: buffer: Return error if no callback is given
Olivier Moysan (1): ASoC: stm32: dfsdm: add stm32_adfsdm_dummy_cb() callback
drivers/iio/buffer/industrialio-buffer-cb.c | 5 +++++ sound/soc/stm/stm32_adfsdm.c | 12 +++++++++++- 2 files changed, 16 insertions(+), 1 deletion(-)
On Sat, 21 Nov 2020 17:14:55 +0100 Nuno Sá nuno.sa@analog.com wrote:
When going through the code of the buffer-cb interface and all it's users, I realized that the stm32_adfsdm driver is calling `iio_channel_get_all_cb()` with NULL for the cb. After going a bit trough the stm drivers, it looks like this is actually intentional. However, it is clear that we have a clear/direct route here for a NULL pointer dereference. This change makes cb a required parameter of the API.
The first patch makes the necessary changes to the stm32_adfsdm driver so that it does not break.
Nuno Sá (1): iio: buffer: Return error if no callback is given
Olivier Moysan (1): ASoC: stm32: dfsdm: add stm32_adfsdm_dummy_cb() callback
drivers/iio/buffer/industrialio-buffer-cb.c | 5 +++++ sound/soc/stm/stm32_adfsdm.c | 12 +++++++++++- 2 files changed, 16 insertions(+), 1 deletion(-)
Applied to the togreg branch of iio.git and pushed out as testing for the autobuilders to do their magic.
Thanks,
Jonathan
participants (4)
-
Jonathan Cameron -
Mark Brown -
Nuno Sá -
Olivier MOYSAN