Re: [PATCH net-next] ipv6: rpl: free skb

From: Kuniyuki Iwashima
Date: Tue Sep 10 2024 - 16:40:47 EST


From: Justin Iurman <justin.iurman@xxxxxxxxx>
Date: Tue, 10 Sep 2024 12:00:32 +0200
> Make rpl_input() free the skb before returning when skb_cow_head()
> fails. Use a "drop" label and goto instructions.
>
> Note: if you think it should be a fix and target "net" instead, let me
> know.

Please do so.

For the future submission, this kind of note and changelog between
each revision can be placed after '---' below so that it will disappear
during merge.

>
> Signed-off-by: Justin Iurman <justin.iurman@xxxxxxxxx>
> ---
> net/ipv6/rpl_iptunnel.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/net/ipv6/rpl_iptunnel.c b/net/ipv6/rpl_iptunnel.c
> index 2c83b7586422..db3c19a42e1c 100644
> --- a/net/ipv6/rpl_iptunnel.c
> +++ b/net/ipv6/rpl_iptunnel.c
> @@ -263,10 +263,8 @@ static int rpl_input(struct sk_buff *skb)
> rlwt = rpl_lwt_lwtunnel(orig_dst->lwtstate);
>
> err = rpl_do_srh(skb, rlwt);
> - if (unlikely(err)) {
> - kfree_skb(skb);
> - return err;
> - }
> + if (unlikely(err))
> + goto drop;
>
> local_bh_disable();
> dst = dst_cache_get(&rlwt->cache);
> @@ -286,9 +284,13 @@ static int rpl_input(struct sk_buff *skb)
>
> err = skb_cow_head(skb, LL_RESERVED_SPACE(dst->dev));
> if (unlikely(err))
> - return err;
> + goto drop;
>
> return dst_input(skb);
> +
> +drop:
> + kfree_skb(skb);
> + return err;
> }
>
> static int nla_put_rpl_srh(struct sk_buff *skb, int attrtype,
> --