Hello Greg,

with v5.18-rc1 in commit

| c359931d2545 ("can: gs_usb: use union and FLEX_ARRAY for data in struct gs_host_frame")

a bug in the gs_usb driver in the usage of usb_free_coherent() was
introduced. With v6.1-rc1

| 62f102c0d156 ("can: gs_usb: remove dma allocations")

the DMA allocation was removed altogether from the driver, fixing the
bug unintentionally.

We can either cherry-pick 62f102c0d156 ("can: gs_usb: remove dma
allocations") on v6.0, v5.19, and v5.18 or apply this patch, which fixes
the usage of usb_free_coherent() only.

regards,
Marc

On 25.11.2022 21:17:27, Marc Kleine-Budde wrote:
> In commit c359931d2545 ("can: gs_usb: use union and FLEX_ARRAY for
> data in struct gs_host_frame") the driver was extended from a compile
> time constant USB transfer size to a transfer size depending on
> attached USB device and configured CAN mode.
> 
> During this conversion the size parameter of some usb_free_coherent()
> calls were not converted. To fix this issue replace the compile time
> constant sizeof(struct gs_host_frame) by hf_size_{rx,tx} for RX
> respectively TX USB transfers.
> 
> Fixes: c359931d2545 ("can: gs_usb: use union and FLEX_ARRAY for data in struct gs_host_frame")
> Cc: Peter Fink <pfink@christ-es.de>
> Cc: stable@vger.kernel.org
> Reported-by: Ryan Edwards <ryan.edwards@gmail.com>
> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
> ---
>  drivers/net/can/usb/gs_usb.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c
> index cd4115a1b81c..57917955b8e4 100644
> --- a/drivers/net/can/usb/gs_usb.c
> +++ b/drivers/net/can/usb/gs_usb.c
> @@ -699,7 +699,7 @@ static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb,
>  	return NETDEV_TX_OK;
>  
>   badidx:
> -	usb_free_coherent(dev->udev, urb->transfer_buffer_length,
> +	usb_free_coherent(dev->udev, dev->hf_size_tx,
>  			  urb->transfer_buffer, urb->transfer_dma);
>   nomem_hf:
>  	usb_free_urb(urb);
> @@ -787,7 +787,7 @@ static int gs_can_open(struct net_device *netdev)
>  
>  				usb_unanchor_urb(urb);
>  				usb_free_coherent(dev->udev,
> -						  sizeof(struct gs_host_frame),
> +						  dev->parent->hf_size_rx,
>  						  buf,
>  						  buf_dma);
>  				usb_free_urb(urb);
> @@ -864,7 +864,7 @@ static int gs_can_close(struct net_device *netdev)
>  		usb_kill_anchored_urbs(&parent->rx_submitted);
>  		for (i = 0; i < GS_MAX_RX_URBS; i++)
>  			usb_free_coherent(dev->udev,
> -					  sizeof(struct gs_host_frame),
> +					  dev->parent->hf_size_rx,
>  					  dev->rxbuf[i],
>  					  dev->rxbuf_dma[i]);
>  	}
> -- 
> 2.35.1
> 
> 
> 

-- 
Pengutronix e.K.                 | Marc Kleine-Budde           |
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