Re: [PATCH] can: ctucanfd: handle skb allocation failure

[Pavel Pisa]

Hello Fedor,

thanks for spotting the problem.

On Tuesday 14 of January 2025 16:21:38 Fedor Pchelkin wrote:
> If skb allocation fails, the pointer to struct can_frame is NULL. This
> is actually handled everywhere inside ctucan_err_interrupt() except for
> the only place.
>
> Add the missed NULL check.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE static
> analysis tool.
>
> Fixes: 2dcb8e8782d8 ("can: ctucanfd: add support for CTU CAN FD open-source
> IP core - bus independent part.") Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>

Acked-by: Pavel Pisa <pisa@xxxxxxxxxxxxxxxx>

> ---
>  drivers/net/can/ctucanfd/ctucanfd_base.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/can/ctucanfd/ctucanfd_base.c
> b/drivers/net/can/ctucanfd/ctucanfd_base.c index 64c349fd4600..f65c1a1e05cc
> 100644
> --- a/drivers/net/can/ctucanfd/ctucanfd_base.c
> +++ b/drivers/net/can/ctucanfd/ctucanfd_base.c
> @@ -867,10 +867,12 @@ static void ctucan_err_interrupt(struct net_device
> *ndev, u32 isr) }
>  			break;
>  		case CAN_STATE_ERROR_ACTIVE:
> -			cf->can_id |= CAN_ERR_CNT;
> -			cf->data[1] = CAN_ERR_CRTL_ACTIVE;
> -			cf->data[6] = bec.txerr;
> -			cf->data[7] = bec.rxerr;
> +			if (skb) {
> +				cf->can_id |= CAN_ERR_CNT;
> +				cf->data[1] = CAN_ERR_CRTL_ACTIVE;
> +				cf->data[6] = bec.txerr;
> +				cf->data[7] = bec.rxerr;
> +			}
>  			break;
>  		default:
>  			netdev_warn(ndev, "unhandled error state (%d:%s)!\n",


-- 

                Pavel Pisa
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