diff mbox series

[1/6] media: usb: siano: Fix allocation of urbs

Message ID 20240410-smatch-v1-1-785d009a852b@chromium.org (mailing list archive)
State New
Headers show
Series media: Fix warnings for smatch and sparse | expand

Commit Message

Ricardo Ribalda April 10, 2024, 9:54 p.m. UTC 
USB urbs must be allocated with usb_alloc_urb. Quoting the manual

Only use this function (usb_init_urb) if you _really_ understand what you
are doing.

Fix the following smatch error:

drivers/media/usb/siano/smsusb.c:53:38: warning: array of flexible structures

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/media/usb/siano/smsusb.c | 28 ++++++++++++++++++++--------
 1 file changed, 20 insertions(+), 8 deletions(-)

Comments

Hans Verkuil April 15, 2024, 10:08 a.m. UTC | #1 
On 10/04/2024 23:54, Ricardo Ribalda wrote:
> USB urbs must be allocated with usb_alloc_urb. Quoting the manual
> 
> Only use this function (usb_init_urb) if you _really_ understand what you
> are doing.
> 
> Fix the following smatch error:
> 
> drivers/media/usb/siano/smsusb.c:53:38: warning: array of flexible structures
> 
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
> ---
>  drivers/media/usb/siano/smsusb.c | 28 ++++++++++++++++++++--------
>  1 file changed, 20 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/media/usb/siano/smsusb.c b/drivers/media/usb/siano/smsusb.c
> index 723510520d092..d85308e0785db 100644
> --- a/drivers/media/usb/siano/smsusb.c
> +++ b/drivers/media/usb/siano/smsusb.c
> @@ -40,7 +40,7 @@ struct smsusb_urb_t {
>  	struct smscore_buffer_t *cb;
>  	struct smsusb_device_t *dev;
>  
> -	struct urb urb;
> +	struct urb *urb;
>  
>  	/* For the bottom half */
>  	struct work_struct wq;
> @@ -160,7 +160,7 @@ static int smsusb_submit_urb(struct smsusb_device_t *dev,
>  	}
>  
>  	usb_fill_bulk_urb(
> -		&surb->urb,
> +		surb->urb,
>  		dev->udev,
>  		usb_rcvbulkpipe(dev->udev, dev->in_ep),
>  		surb->cb->p,
> @@ -168,9 +168,9 @@ static int smsusb_submit_urb(struct smsusb_device_t *dev,
>  		smsusb_onresponse,
>  		surb
>  	);
> -	surb->urb.transfer_flags |= URB_FREE_BUFFER;
> +	surb->urb->transfer_flags |= URB_FREE_BUFFER;
>  
> -	return usb_submit_urb(&surb->urb, GFP_ATOMIC);
> +	return usb_submit_urb(surb->urb, GFP_ATOMIC);
>  }
>  
>  static void smsusb_stop_streaming(struct smsusb_device_t *dev)
> @@ -178,7 +178,7 @@ static void smsusb_stop_streaming(struct smsusb_device_t *dev)
>  	int i;
>  
>  	for (i = 0; i < MAX_URBS; i++) {
> -		usb_kill_urb(&dev->surbs[i].urb);
> +		usb_kill_urb(dev->surbs[i].urb);
>  		if (dev->surbs[i].wq.func)
>  			cancel_work_sync(&dev->surbs[i].wq);
>  
> @@ -338,6 +338,8 @@ static void smsusb_term_device(struct usb_interface *intf)
>  	struct smsusb_device_t *dev = usb_get_intfdata(intf);
>  
>  	if (dev) {
> +		int i;
> +
>  		dev->state = SMSUSB_DISCONNECTED;
>  
>  		smsusb_stop_streaming(dev);
> @@ -346,6 +348,9 @@ static void smsusb_term_device(struct usb_interface *intf)
>  		if (dev->coredev)
>  			smscore_unregister_device(dev->coredev);
>  
> +		for (i = 0; i < MAX_URBS; i++)
> +			usb_free_urb(dev->surbs[i].urb);
> +
>  		pr_debug("device 0x%p destroyed\n", dev);
>  		kfree(dev);
>  	}
> @@ -390,6 +395,7 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
>  	void *mdev;
>  	int i, rc;
>  	int align = 0;
> +	int n_urb = 0;
>  
>  	/* create device object */
>  	dev = kzalloc(sizeof(struct smsusb_device_t), GFP_KERNEL);
> @@ -461,9 +467,11 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
>  	dev->coredev->is_usb_device = true;
>  
>  	/* initialize urbs */
> -	for (i = 0; i < MAX_URBS; i++) {
> -		dev->surbs[i].dev = dev;
> -		usb_init_urb(&dev->surbs[i].urb);
> +	for (n_urb = 0; n_urb < MAX_URBS; n_urb++) {
> +		dev->surbs[n_urb].dev = dev;
> +		dev->surbs[n_urb].urb = usb_alloc_urb(0, GFP_KERNEL);
> +		if (!dev->surbs[n_urb].urb)
> +			goto free_urbs;
>  	}

After allocating the URBs there are a few more error paths that do
'goto err_unregister_device;' instead of 'goto free_urbs;'. From what
I can see, those need to go through 'free_urbs' as well.

>  
>  	pr_debug("smsusb_start_streaming(...).\n");
> @@ -485,6 +493,10 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
>  
>  	return rc;
>  
> +free_urbs:
> +	for (i = 0; i < n_urb; i++)
> +		usb_free_urb(dev->surbs[n_urb].urb);

Would it be better to also assign NULL to dev->surbs[n_urb].urb?
That way there are no invalid pointers that can mess up things.

Regards,

	Hans

> +
>  err_unregister_device:
>  	smsusb_term_device(intf);
>  #ifdef CONFIG_MEDIA_CONTROLLER_DVB
>
Hans Verkuil April 15, 2024, 11:47 a.m. UTC | #2 
On 15/04/2024 12:08, Hans Verkuil wrote:
> On 10/04/2024 23:54, Ricardo Ribalda wrote:
>> USB urbs must be allocated with usb_alloc_urb. Quoting the manual
>>
>> Only use this function (usb_init_urb) if you _really_ understand what you
>> are doing.
>>
>> Fix the following smatch error:
>>
>> drivers/media/usb/siano/smsusb.c:53:38: warning: array of flexible structures
>>
>> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
>> ---
>>  drivers/media/usb/siano/smsusb.c | 28 ++++++++++++++++++++--------
>>  1 file changed, 20 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/media/usb/siano/smsusb.c b/drivers/media/usb/siano/smsusb.c
>> index 723510520d092..d85308e0785db 100644
>> --- a/drivers/media/usb/siano/smsusb.c
>> +++ b/drivers/media/usb/siano/smsusb.c
>> @@ -40,7 +40,7 @@ struct smsusb_urb_t {
>>  	struct smscore_buffer_t *cb;
>>  	struct smsusb_device_t *dev;
>>  
>> -	struct urb urb;
>> +	struct urb *urb;
>>  
>>  	/* For the bottom half */
>>  	struct work_struct wq;
>> @@ -160,7 +160,7 @@ static int smsusb_submit_urb(struct smsusb_device_t *dev,
>>  	}
>>  
>>  	usb_fill_bulk_urb(
>> -		&surb->urb,
>> +		surb->urb,
>>  		dev->udev,
>>  		usb_rcvbulkpipe(dev->udev, dev->in_ep),
>>  		surb->cb->p,
>> @@ -168,9 +168,9 @@ static int smsusb_submit_urb(struct smsusb_device_t *dev,
>>  		smsusb_onresponse,
>>  		surb
>>  	);
>> -	surb->urb.transfer_flags |= URB_FREE_BUFFER;
>> +	surb->urb->transfer_flags |= URB_FREE_BUFFER;
>>  
>> -	return usb_submit_urb(&surb->urb, GFP_ATOMIC);
>> +	return usb_submit_urb(surb->urb, GFP_ATOMIC);
>>  }
>>  
>>  static void smsusb_stop_streaming(struct smsusb_device_t *dev)
>> @@ -178,7 +178,7 @@ static void smsusb_stop_streaming(struct smsusb_device_t *dev)
>>  	int i;
>>  
>>  	for (i = 0; i < MAX_URBS; i++) {
>> -		usb_kill_urb(&dev->surbs[i].urb);
>> +		usb_kill_urb(dev->surbs[i].urb);
>>  		if (dev->surbs[i].wq.func)
>>  			cancel_work_sync(&dev->surbs[i].wq);
>>  
>> @@ -338,6 +338,8 @@ static void smsusb_term_device(struct usb_interface *intf)
>>  	struct smsusb_device_t *dev = usb_get_intfdata(intf);
>>  
>>  	if (dev) {
>> +		int i;
>> +
>>  		dev->state = SMSUSB_DISCONNECTED;
>>  
>>  		smsusb_stop_streaming(dev);
>> @@ -346,6 +348,9 @@ static void smsusb_term_device(struct usb_interface *intf)
>>  		if (dev->coredev)
>>  			smscore_unregister_device(dev->coredev);
>>  
>> +		for (i = 0; i < MAX_URBS; i++)
>> +			usb_free_urb(dev->surbs[i].urb);
>> +
>>  		pr_debug("device 0x%p destroyed\n", dev);
>>  		kfree(dev);
>>  	}
>> @@ -390,6 +395,7 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
>>  	void *mdev;
>>  	int i, rc;
>>  	int align = 0;
>> +	int n_urb = 0;
>>  
>>  	/* create device object */
>>  	dev = kzalloc(sizeof(struct smsusb_device_t), GFP_KERNEL);
>> @@ -461,9 +467,11 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
>>  	dev->coredev->is_usb_device = true;
>>  
>>  	/* initialize urbs */
>> -	for (i = 0; i < MAX_URBS; i++) {
>> -		dev->surbs[i].dev = dev;
>> -		usb_init_urb(&dev->surbs[i].urb);
>> +	for (n_urb = 0; n_urb < MAX_URBS; n_urb++) {
>> +		dev->surbs[n_urb].dev = dev;
>> +		dev->surbs[n_urb].urb = usb_alloc_urb(0, GFP_KERNEL);
>> +		if (!dev->surbs[n_urb].urb)
>> +			goto free_urbs;
>>  	}
> 
> After allocating the URBs there are a few more error paths that do
> 'goto err_unregister_device;' instead of 'goto free_urbs;'. From what
> I can see, those need to go through 'free_urbs' as well.
> 
>>  
>>  	pr_debug("smsusb_start_streaming(...).\n");
>> @@ -485,6 +493,10 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
>>  
>>  	return rc;
>>  
>> +free_urbs:
>> +	for (i = 0; i < n_urb; i++)
>> +		usb_free_urb(dev->surbs[n_urb].urb);
> 
> Would it be better to also assign NULL to dev->surbs[n_urb].urb?
> That way there are no invalid pointers that can mess up things.

Ricardo, just post a v2 of this patch. I posted a PR for the other
patches. Nice work, BTW!

Regards,

	Hans

> 
> Regards,
> 
> 	Hans
> 
>> +
>>  err_unregister_device:
>>  	smsusb_term_device(intf);
>>  #ifdef CONFIG_MEDIA_CONTROLLER_DVB
>>
> 
>
diff mbox series

Patch

diff --git a/drivers/media/usb/siano/smsusb.c b/drivers/media/usb/siano/smsusb.c
index 723510520d092..d85308e0785db 100644
--- a/drivers/media/usb/siano/smsusb.c
+++ b/drivers/media/usb/siano/smsusb.c
@@ -40,7 +40,7 @@  struct smsusb_urb_t {
 	struct smscore_buffer_t *cb;
 	struct smsusb_device_t *dev;
 
-	struct urb urb;
+	struct urb *urb;
 
 	/* For the bottom half */
 	struct work_struct wq;
@@ -160,7 +160,7 @@  static int smsusb_submit_urb(struct smsusb_device_t *dev,
 	}
 
 	usb_fill_bulk_urb(
-		&surb->urb,
+		surb->urb,
 		dev->udev,
 		usb_rcvbulkpipe(dev->udev, dev->in_ep),
 		surb->cb->p,
@@ -168,9 +168,9 @@  static int smsusb_submit_urb(struct smsusb_device_t *dev,
 		smsusb_onresponse,
 		surb
 	);
-	surb->urb.transfer_flags |= URB_FREE_BUFFER;
+	surb->urb->transfer_flags |= URB_FREE_BUFFER;
 
-	return usb_submit_urb(&surb->urb, GFP_ATOMIC);
+	return usb_submit_urb(surb->urb, GFP_ATOMIC);
 }
 
 static void smsusb_stop_streaming(struct smsusb_device_t *dev)
@@ -178,7 +178,7 @@  static void smsusb_stop_streaming(struct smsusb_device_t *dev)
 	int i;
 
 	for (i = 0; i < MAX_URBS; i++) {
-		usb_kill_urb(&dev->surbs[i].urb);
+		usb_kill_urb(dev->surbs[i].urb);
 		if (dev->surbs[i].wq.func)
 			cancel_work_sync(&dev->surbs[i].wq);
 
@@ -338,6 +338,8 @@  static void smsusb_term_device(struct usb_interface *intf)
 	struct smsusb_device_t *dev = usb_get_intfdata(intf);
 
 	if (dev) {
+		int i;
+
 		dev->state = SMSUSB_DISCONNECTED;
 
 		smsusb_stop_streaming(dev);
@@ -346,6 +348,9 @@  static void smsusb_term_device(struct usb_interface *intf)
 		if (dev->coredev)
 			smscore_unregister_device(dev->coredev);
 
+		for (i = 0; i < MAX_URBS; i++)
+			usb_free_urb(dev->surbs[i].urb);
+
 		pr_debug("device 0x%p destroyed\n", dev);
 		kfree(dev);
 	}
@@ -390,6 +395,7 @@  static int smsusb_init_device(struct usb_interface *intf, int board_id)
 	void *mdev;
 	int i, rc;
 	int align = 0;
+	int n_urb = 0;
 
 	/* create device object */
 	dev = kzalloc(sizeof(struct smsusb_device_t), GFP_KERNEL);
@@ -461,9 +467,11 @@  static int smsusb_init_device(struct usb_interface *intf, int board_id)
 	dev->coredev->is_usb_device = true;
 
 	/* initialize urbs */
-	for (i = 0; i < MAX_URBS; i++) {
-		dev->surbs[i].dev = dev;
-		usb_init_urb(&dev->surbs[i].urb);
+	for (n_urb = 0; n_urb < MAX_URBS; n_urb++) {
+		dev->surbs[n_urb].dev = dev;
+		dev->surbs[n_urb].urb = usb_alloc_urb(0, GFP_KERNEL);
+		if (!dev->surbs[n_urb].urb)
+			goto free_urbs;
 	}
 
 	pr_debug("smsusb_start_streaming(...).\n");
@@ -485,6 +493,10 @@  static int smsusb_init_device(struct usb_interface *intf, int board_id)
 
 	return rc;
 
+free_urbs:
+	for (i = 0; i < n_urb; i++)
+		usb_free_urb(dev->surbs[n_urb].urb);
+
 err_unregister_device:
 	smsusb_term_device(intf);
 #ifdef CONFIG_MEDIA_CONTROLLER_DVB