[PATCH 08/10] net: fastboot: use net_eth_to_udp() for packet parsing

[Ahmad Fatoum]

On 4/2/26 8:36 AM, Sascha Hauer wrote:
> Replace the separate net_eth_to_udplen(), net_eth_to_udphdr() and
> net_eth_to_udp_payload() calls with the new consolidated
> net_eth_to_udp() helper.
> 
> The direct net_eth_to_iphdr() call is kept because fastboot needs
> access to the IP header for source address handling and tot_len based
> fragment detection.
> 
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> Co-Authored-By: Claude Opus 4.6 <noreply at anthropic.com>

Reviewed-by: Ahmad Fatoum <a.fatoum at pengutronix.de>

> ---
>  net/fastboot.c | 21 ++++++++++++++-------
>  1 file changed, 14 insertions(+), 7 deletions(-)
> 
> diff --git a/net/fastboot.c b/net/fastboot.c
> index 263d8abaa2..506af00cb8 100644
> --- a/net/fastboot.c
> +++ b/net/fastboot.c
> @@ -351,17 +351,24 @@ static void fastboot_check_retransmit(struct fastboot_net *fbn,
>  
>  static void fastboot_handler(void *ctx, char *packet, unsigned int raw_len)
>  {
> -	unsigned int len = net_eth_to_udplen(packet);
>  	struct ethernet *eth_header = (struct ethernet *)packet;
>  	struct iphdr *ip_header = net_eth_to_iphdr(packet);
> -	struct udphdr *udp_header = net_eth_to_udphdr(packet);
> -	char *payload = net_eth_to_udp_payload(packet);
>  	struct fastboot_net *fbn = ctx;
> +	struct net_udp_pkt udp;
>  	struct fastboot_header header;
> -	char *fastboot_data = payload + sizeof(header);
> -	u16 tot_len = ntohs(ip_header->tot_len);
> +	char *payload, *fastboot_data;
> +	unsigned int len;
> +	u16 tot_len;
>  	int ret;
>  
> +	if (net_eth_to_udp(packet, raw_len, &udp))
> +		return;
> +
> +	payload = udp.payload;
> +	len = udp.len;
> +	fastboot_data = payload + sizeof(header);
> +	tot_len = ntohs(ip_header->tot_len);
> +
>  	/* catch bogus tot_len values */
>  	if ((char *)ip_header - packet + tot_len > raw_len)
>  		return;
> @@ -392,7 +399,7 @@ static void fastboot_handler(void *ctx, char *packet, unsigned int raw_len)
>  
>  	memcpy(fbn->net_con->et->et_dest, eth_header->et_src, ETH_ALEN);
>  	net_copy_ip(&fbn->net_con->ip->daddr, &ip_header->saddr);
> -	fbn->net_con->udp->uh_dport = udp_header->uh_sport;
> +	fbn->net_con->udp->uh_dport = udp.udp->uh_sport;
>  
>  	switch (header.id) {
>  	case FASTBOOT_QUERY:
> @@ -404,7 +411,7 @@ static void fastboot_handler(void *ctx, char *packet, unsigned int raw_len)
>  			break;
>  		}
>  		fbn->host_addr = net_read_ip(&ip_header->saddr);
> -		fbn->host_port = udp_header->uh_sport;
> +		fbn->host_port = udp.udp->uh_sport;
>  		memcpy(fbn->host_mac, eth_header->et_src, ETH_ALEN);
>  		fastboot_net_abort(fbn);
>  		/* poller just unregistered in fastboot_net_abort() */
> 

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