Re: [PATCH-next] usb: gadget: dereference before null check

[Greg Kroah-Hartman]

On Wed, Jun 29, 2022 at 11:26:05AM +0530, SebinSebastian wrote:
> From: Sebin Sebastian <mailmesebin00@xxxxxxxxx>
> 
> Fix coverity warning dereferencing before null check. _ep and desc is
> deferenced on all paths until the check for null. Move the
> initilizations after the check for null.
> Coverity issue: 1518209
> 
> Signed-off-by: Sebin Sebastian <mailmesebin00@xxxxxxxxx>
> ---
>  drivers/usb/gadget/udc/aspeed_udc.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/gadget/udc/aspeed_udc.c b/drivers/usb/gadget/udc/aspeed_udc.c
> index d75a4e070bf7..4f158030e2cc 100644
> --- a/drivers/usb/gadget/udc/aspeed_udc.c
> +++ b/drivers/usb/gadget/udc/aspeed_udc.c
> @@ -341,10 +341,6 @@ static void ast_udc_stop_activity(struct ast_udc_dev *udc)
>  static int ast_udc_ep_enable(struct usb_ep *_ep,
>  			     const struct usb_endpoint_descriptor *desc)
>  {
> -	u16 maxpacket = usb_endpoint_maxp(desc);
> -	struct ast_udc_ep *ep = to_ast_ep(_ep);
> -	struct ast_udc_dev *udc = ep->udc;
> -	u8 epnum = usb_endpoint_num(desc);
>  	unsigned long flags;
>  	u32 ep_conf = 0;
>  	u8 dir_in;
> @@ -355,6 +351,12 @@ static int ast_udc_ep_enable(struct usb_ep *_ep,
>  		EP_DBG(ep, "Failed, invalid EP enable param\n");
>  		return -EINVAL;
>  	}
> +
> +	u16 maxpacket = usb_endpoint_maxp(desc);
> +	struct ast_udc_ep *ep = to_ast_ep(_ep);
> +	struct ast_udc_dev *udc = ep->udc;
> +	u8 epnum = usb_endpoint_num(desc);
> +
>  
>  	if (!udc->driver) {
>  		EP_DBG(ep, "bogus device state\n");
> -- 
> 2.34.1
> 

Hi,

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