Re: [PATCH] mfd: mc13xxx: i2c/spi Fix to avoid NULL pointer dereference

2019-04-02 Thread Lee Jones
On Mon, 18 Mar 2019, Aditya Pakki wrote:

> of_match_device can return NULL if no matching device is found. The patches
> avoids a scenario causing null pointer dereference.
> 
> Signed-off-by: Aditya Pakki 
> ---
>  drivers/mfd/mc13xxx-i2c.c | 2 ++
>  drivers/mfd/mc13xxx-spi.c | 2 ++
>  2 files changed, 4 insertions(+)
> 
> diff --git a/drivers/mfd/mc13xxx-i2c.c b/drivers/mfd/mc13xxx-i2c.c
> index 67e4c9aa7d18..1fbc9713bb9a 100644
> --- a/drivers/mfd/mc13xxx-i2c.c
> +++ b/drivers/mfd/mc13xxx-i2c.c
> @@ -80,6 +80,8 @@ static int mc13xxx_i2c_probe(struct i2c_client *client,
>   if (client->dev.of_node) {
>   const struct of_device_id *of_id =
>   of_match_device(mc13xxx_dt_ids, >dev);
> + if (!of_id)
> + return -ENODEV;

Are you sure this can happen?

I don't think this is possible if client->dev.of_node is non-NULL.

The 'if (client->dev.of_node)' above should see to that.

>   mc13xxx->variant = of_id->data;
>   } else {
>   mc13xxx->variant = (void *)id->driver_data;
> diff --git a/drivers/mfd/mc13xxx-spi.c b/drivers/mfd/mc13xxx-spi.c
> index ee3411cc5ce4..c044a02bdb64 100644
> --- a/drivers/mfd/mc13xxx-spi.c
> +++ b/drivers/mfd/mc13xxx-spi.c
> @@ -158,6 +158,8 @@ static int mc13xxx_spi_probe(struct spi_device *spi)
>   if (spi->dev.of_node) {
>   const struct of_device_id *of_id =
>   of_match_device(mc13xxx_dt_ids, >dev);
> + if (!of_id)
> + return -ENODEV;
>  
>   mc13xxx->variant = of_id->data;
>   } else {

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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[PATCH] mfd: mc13xxx: i2c/spi Fix to avoid NULL pointer dereference

2019-03-18 Thread Aditya Pakki
of_match_device can return NULL if no matching device is found. The patches
avoids a scenario causing null pointer dereference.

Signed-off-by: Aditya Pakki 
---
 drivers/mfd/mc13xxx-i2c.c | 2 ++
 drivers/mfd/mc13xxx-spi.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/drivers/mfd/mc13xxx-i2c.c b/drivers/mfd/mc13xxx-i2c.c
index 67e4c9aa7d18..1fbc9713bb9a 100644
--- a/drivers/mfd/mc13xxx-i2c.c
+++ b/drivers/mfd/mc13xxx-i2c.c
@@ -80,6 +80,8 @@ static int mc13xxx_i2c_probe(struct i2c_client *client,
if (client->dev.of_node) {
const struct of_device_id *of_id =
of_match_device(mc13xxx_dt_ids, >dev);
+   if (!of_id)
+   return -ENODEV;
mc13xxx->variant = of_id->data;
} else {
mc13xxx->variant = (void *)id->driver_data;
diff --git a/drivers/mfd/mc13xxx-spi.c b/drivers/mfd/mc13xxx-spi.c
index ee3411cc5ce4..c044a02bdb64 100644
--- a/drivers/mfd/mc13xxx-spi.c
+++ b/drivers/mfd/mc13xxx-spi.c
@@ -158,6 +158,8 @@ static int mc13xxx_spi_probe(struct spi_device *spi)
if (spi->dev.of_node) {
const struct of_device_id *of_id =
of_match_device(mc13xxx_dt_ids, >dev);
+   if (!of_id)
+   return -ENODEV;
 
mc13xxx->variant = of_id->data;
} else {
-- 
2.17.1