Re: [PATCH] ip_frag: support IPv6 reassembly with extensions

[Stephen Hemminger <stephen@networkplumber.org>]

On Mon, 26 Aug 2024 13:23:28 +0200
<vignesh.purushotham.srinivas@ericsson.com> wrote:

> diff --git a/lib/ip_frag/ip_reassembly.h b/lib/ip_frag/ip_reassembly.h
> index 54afed5417..429e74f1b3 100644
> --- a/lib/ip_frag/ip_reassembly.h
> +++ b/lib/ip_frag/ip_reassembly.h
> @@ -54,6 +54,8 @@ struct __rte_cache_aligned ip_frag_pkt {
>  	uint32_t total_size;                   /* expected reassembled size */
>  	uint32_t frag_size;                    /* size of fragments received */
>  	uint32_t last_idx;                     /* index of next entry to fill */
> +	uint32_t exts_len;                     /* length of extension hdrs for first fragment */
> +	uint8_t *next_proto;                   /* pointer of the next_proto field */
>  	struct ip_frag frags[IP_MAX_FRAG_NUM]; /* fragments */
>  };

This creates a 32 bit hole in the structure.
Better to put next_proto after the start field.

> +
> +	while (next_proto != IPPROTO_FRAGMENT &&
> +		num_exts < MAX_NUM_IPV6_EXTS &&
> +		(next_proto = rte_ipv6_get_next_ext(
> +		*last_ext, next_proto, &ext_len)) >= 0) {

I would break up this loop condition for clarity.
Something like:

	while (next_proto != IPPROTO_FRAGMENT && num_exts < MAX_NUM_IPV6_EXTS) {
		next_proto = rte_ipv6_get_next_ext(*last_ext, next_proto, &ext_len);
		if (next_proto < 0)
			break

Also, need a new test cases for this.