From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Westphal <fw@strlen.de>
Subject: Re: .config for iptables icmp rule delete failure
Date: Tue, 9 May 2017 04:32:00 +0200
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Cc: Florian Westphal <fw@strlen.de>,
        Richard Guy Briggs <rgb@redhat.com>, fwestpha@redhat.com,
        netfilter-devel <netfilter-devel@vger.kernel.org>,
        pmoore@redhat.com, pvrabec@redhat.com
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
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Willem de Bruijn <willemdebruijn.kernel@gmail.com> wrote:

> Thanks, Florian. Also for the detailed context. I'm having a look.
> The following might be sufficient. It fixes the given example for me.
> 
> @@ -288,6 +288,10 @@ int xt_data_to_user(void __user *dst, const void *src,
>         usersize = usersize ? : size;
>         if (copy_to_user(dst, src, usersize))
>                 return -EFAULT;
> +       size = XT_ALIGN(size);
>         if (usersize != size && clear_user(dst + usersize, size - usersize))
>                 return -EFAULT;

Looks good, but I think this needs a tweak for compat case (use of
COMPAT_XT_ALIGN()).