[PATCH] ALSA: portman2x4: fix NULL pointer dereference

[PATCH] ALSA: portman2x4: fix NULL pointer dereference

[Sudip Mukherjee]

While registering pardev, the irq_func was also registered. As a result
when we tried to probe for the card, an interrupt was generated and in
the ISR we tried to dereference private_data. But private_data is still
NULL as we have not yet done portman_create(). Lets probe for the device
after card is created.

Fixes: e6a1b7e88046 ("ALSA: portman2x4 - use new parport device model")
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
---
 sound/drivers/portman2x4.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/sound/drivers/portman2x4.c b/sound/drivers/portman2x4.c
index 362533f..189e3e7 100644
--- a/sound/drivers/portman2x4.c
+++ b/sound/drivers/portman2x4.c
@@ -762,11 +762,6 @@ static int snd_portman_probe(struct platform_device *pdev)
 		err = -EIO;
 		goto free_pardev;
 	}
-	err = portman_probe(p);
-	if (err) {
-		err = -EIO;
-		goto release_pardev;
-	}
 
 	if ((err = portman_create(card, pardev, &pm)) < 0) {
 		snd_printd("Cannot create main component\n");
@@ -774,6 +769,12 @@ static int snd_portman_probe(struct platform_device *pdev)
 	}
 	card->private_data = pm;
 	card->private_free = snd_portman_card_private_free;
+
+	err = portman_probe(p);
+	if (err) {
+		err = -EIO;
+		goto __err;
+	}
 	
 	if ((err = snd_portman_rawmidi_create(card)) < 0) {
 		snd_printd("Creating Rawmidi component failed\n");
-- 
1.9.1

Re: [PATCH] ALSA: portman2x4: fix NULL pointer dereference

[Takashi Iwai]

On Wed, 02 Mar 2016 12:40:30 +0100,
Sudip Mukherjee wrote:
> 
> While registering pardev, the irq_func was also registered. As a result
> when we tried to probe for the card, an interrupt was generated and in
> the ISR we tried to dereference private_data. But private_data is still
> NULL as we have not yet done portman_create(). Lets probe for the device
> after card is created.
> 
> Fixes: e6a1b7e88046 ("ALSA: portman2x4 - use new parport device model")
> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>

Applied, thanks.


Takashi

> ---
>  sound/drivers/portman2x4.c | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/sound/drivers/portman2x4.c b/sound/drivers/portman2x4.c
> index 362533f..189e3e7 100644
> --- a/sound/drivers/portman2x4.c
> +++ b/sound/drivers/portman2x4.c
> @@ -762,11 +762,6 @@ static int snd_portman_probe(struct platform_device *pdev)
>  		err = -EIO;
>  		goto free_pardev;
>  	}
> -	err = portman_probe(p);
> -	if (err) {
> -		err = -EIO;
> -		goto release_pardev;
> -	}
>  
>  	if ((err = portman_create(card, pardev, &pm)) < 0) {
>  		snd_printd("Cannot create main component\n");
> @@ -774,6 +769,12 @@ static int snd_portman_probe(struct platform_device *pdev)
>  	}
>  	card->private_data = pm;
>  	card->private_free = snd_portman_card_private_free;
> +
> +	err = portman_probe(p);
> +	if (err) {
> +		err = -EIO;
> +		goto __err;
> +	}
>  	
>  	if ((err = snd_portman_rawmidi_create(card)) < 0) {
>  		snd_printd("Creating Rawmidi component failed\n");
> -- 
> 1.9.1
> 
>