Re: [PATCH] firewire: nosy: Fix dma_free_coherent() size

Christophe JAILLET <[email protected]> Tue, 16 Dec 2025 18:47:30 +0100
Newsgroups gmane.linux.kernel,gmane.linux.kernel.firewire.devel
Message-ID <[email protected]>
Le 16/12/2025 à 17:54, Thomas Fourier a écrit :
> It looks like the buffer allocated and mapped in add_card() is done
> with size RCV_BUFFER_SIZE which is 16 KB and 4KB.
> 
> Fixes: 286468210d83 ("firewire: new driver: nosy - IEEE 1394 traffic sniffer")
> Signed-off-by: Thomas Fourier <[email protected]>

Reviewed-by: Christophe JAILLET <[email protected]>

And for the records, see [1].

CJ

[1]: 
https://lore.kernel.org/lkml/[email protected]/

> ---
>   drivers/firewire/nosy.c | 10 +++++-----
>   1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/firewire/nosy.c b/drivers/firewire/nosy.c
> index ea31ac7ac1ca..f562e82e5438 100644
> --- a/drivers/firewire/nosy.c
> +++ b/drivers/firewire/nosy.c
> @@ -494,6 +494,8 @@ irq_handler(int irq, void *device)
>   	return IRQ_HANDLED;
>   }
>   
> +#define RCV_BUFFER_SIZE (16 * 1024)

Maybe this could be moved at the top of the file when #define are 
usually placed.

> +
>   static void
>   remove_card(struct pci_dev *dev)
>   {
> @@ -517,16 +519,14 @@ remove_card(struct pci_dev *dev)
>   			  lynx->rcv_start_pcl, lynx->rcv_start_pcl_bus);
>   	dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),
>   			  lynx->rcv_pcl, lynx->rcv_pcl_bus);
> -	dma_free_coherent(&lynx->pci_device->dev, PAGE_SIZE, lynx->rcv_buffer,
> -			  lynx->rcv_buffer_bus);
> +	dma_free_coherent(&lynx->pci_device->dev, RCV_BUFFER_SIZE,
> +			  lynx->rcv_buffer, lynx->rcv_buffer_bus);
>   
>   	iounmap(lynx->registers);
>   	pci_disable_device(dev);
>   	lynx_put(lynx);
>   }
>   
> -#define RCV_BUFFER_SIZE (16 * 1024)
> -
>   static int
>   add_card(struct pci_dev *dev, const struct pci_device_id *unused)
>   {
> @@ -680,7 +680,7 @@ add_card(struct pci_dev *dev, const struct pci_device_id *unused)
>   		dma_free_coherent(&lynx->pci_device->dev, sizeof(struct pcl),
>   				  lynx->rcv_pcl, lynx->rcv_pcl_bus);
>   	if (lynx->rcv_buffer)
> -		dma_free_coherent(&lynx->pci_device->dev, PAGE_SIZE,
> +		dma_free_coherent(&lynx->pci_device->dev, RCV_BUFFER_SIZE,
>   				  lynx->rcv_buffer, lynx->rcv_buffer_bus);
>   	iounmap(lynx->registers);
>