From: Paolo Abeni <[email protected]>
Date: Fri, 21 Jul 2017 15:55:18 +0200
> diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
> index 93157f2..fdda973 100644
> --- a/net/ipv4/ip_options.c
> +++ b/net/ipv4/ip_options.c
> @@ -174,9 +174,6 @@ int __ip_options_echo(struct ip_options *dopt, struct
> sk_buff *skb,
> doffset -= 4;
> }
> if (doffset > 3) {
> - __be32 daddr = fib_compute_spec_dst(skb);
> -
> - memcpy(&start[doffset-1], &daddr, 4);
> dopt->faddr = faddr;
This transformation is required, but in the destination not the source.
The red flag is that we are indexing 'start' with 'doffset' instead of
'soffset'.