From: Hangbin Liu <liuhangbin@gmail.com>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: Network Development <netdev@vger.kernel.org>,
Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
Jakub Kicinski <kuba@kernel.org>,
"David S . Miller" <davem@davemloft.net>,
Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCHv2 net 2/2] IPv6: reply ICMP error if the first fragment don't include all headers
Date: Thu, 22 Oct 2020 17:12:05 +0800 [thread overview]
Message-ID: <20201022091205.GN2531@dhcp-12-153.nay.redhat.com> (raw)
In-Reply-To: <CA+FuTSdCG4yVDb85M=fChfrkU9=F7j88TJujJy_y0pv-Ks_MwQ@mail.gmail.com>
Hi Willem,
Thanks for the comments, see replies below.
On Wed, Oct 21, 2020 at 10:02:55AM -0400, Willem de Bruijn wrote:
> > + is_frag = (ipv6_find_hdr(skb, &offs, NEXTHDR_FRAGMENT, NULL, NULL) == NEXTHDR_FRAGMENT);
> > +
>
> ipv6_skip_exthdr already walks all headers. Should we not already see
> frag_off != 0 if skipped over a fragment header? Analogous to the test
> in ipv6_frag_rcv below.
Ah, yes, I forgot we can use this check.
> > + nexthdr = hdr->nexthdr;
> > + offset = ipv6_skip_exthdr(skb, skb_transport_offset(skb), &nexthdr, &frag_off);
> > + if (offset >= 0 && frag_off == htons(IP6_MF) && (offset + 1) > skb->len) {
>
> Offset +1 does not fully test "all headers through an upper layer
> header". You note the caveat in your commit message. Perhaps for the
> small list of common protocols at least use a length derived from
> nexthdr?
Do you mean check the header like
if (nexthdr == IPPROTO_ICMPV6)
offset = offset + seizeof(struct icmp6hdr);
else if (nexthdr == ...)
offset = ...
else
offset += 1;
if (frag_off == htons(IP6_MF) && offset > skb->len) {
icmpv6_param_prob(skb, ICMPV6_HDR_INCOMP, 0);
return -1;
}
Another questions is how to define the list, does TCP/UDP/SCTP/ICMPv6 enough?
Thanks
Hangbin
next prev parent reply other threads:[~2020-10-22 9:12 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-07 3:55 [PATCH net 0/2] IPv6: reply ICMP error with fragment doesn't contain all headers Hangbin Liu
2020-10-07 3:55 ` [PATCH net 1/2] ICMPv6: Add ICMPv6 Parameter Problem, code 3 definition Hangbin Liu
2020-10-07 3:55 ` [PATCH net 2/2] IPv6: reply ICMP error if the first fragment don't include all headers Hangbin Liu
2020-10-07 9:35 ` Eric Dumazet
2020-10-08 8:30 ` Hangbin Liu
2020-10-08 9:47 ` Eric Dumazet
2020-10-09 10:07 ` Hangbin Liu
2020-10-07 14:58 ` Jakub Kicinski
2020-10-08 8:36 ` Hangbin Liu
2020-10-21 4:20 ` [PATCHv2 net 0/2] IPv6: reply ICMP error with fragment doesn't contain " Hangbin Liu
2020-10-21 4:20 ` [PATCHv2 net 1/2] ICMPv6: Add ICMPv6 Parameter Problem, code 3 definition Hangbin Liu
2020-10-21 4:20 ` [PATCHv2 net 2/2] IPv6: reply ICMP error if the first fragment don't include all headers Hangbin Liu
2020-10-21 14:02 ` Willem de Bruijn
2020-10-22 9:12 ` Hangbin Liu [this message]
2020-10-22 15:46 ` Willem de Bruijn
2020-10-23 6:43 ` [PATCHv3 net 0/2] IPv6: reply ICMP error if fragment doesn't contain " Hangbin Liu
2020-10-23 6:43 ` [PATCHv3 net 1/2] ICMPv6: Add ICMPv6 Parameter Problem, code 3 definition Hangbin Liu
2020-10-23 6:43 ` [PATCHv3 net 2/2] IPv6: reply ICMP error if the first fragment doesn't include all headers Hangbin Liu
2020-10-23 18:18 ` Jakub Kicinski
2020-10-26 7:29 ` [PATCHv4 net 0/2] IPv6: reply ICMP error if fragment doesn't contain " Hangbin Liu
2020-10-26 7:29 ` [PATCHv4 net 1/2] ICMPv6: Add ICMPv6 Parameter Problem, code 3 definition Hangbin Liu
2020-10-26 7:29 ` [PATCHv4 net 2/2] IPv6: reply ICMP error if the first fragment don't include all headers Hangbin Liu
2020-10-26 8:09 ` Georg Kohmann (geokohma)
2020-10-26 12:55 ` Hangbin Liu
2020-10-26 14:49 ` Georg Kohmann (geokohma)
2020-10-27 2:28 ` [PATCHv5 net 0/2] IPv6: reply ICMP error if fragment doesn't contain " Hangbin Liu
2020-10-27 2:28 ` [PATCHv5 net 1/2] ICMPv6: Add ICMPv6 Parameter Problem, code 3 definition Hangbin Liu
2020-10-27 2:28 ` [PATCHv5 net 2/2] IPv6: reply ICMP error if the first fragment don't include all headers Hangbin Liu
2020-10-27 7:57 ` Georg Kohmann (geokohma)
2020-10-27 9:57 ` Hangbin Liu
2020-10-27 10:20 ` Georg Kohmann (geokohma)
2020-10-30 15:31 ` Willem de Bruijn
2020-10-30 18:39 ` Georg Kohmann (geokohma)
2020-10-27 12:33 ` [PATCHv6 net 0/2] IPv6: reply ICMP error if fragment doesn't contain " Hangbin Liu
2020-10-27 12:33 ` [PATCHv6 net 1/2] ICMPv6: Add ICMPv6 Parameter Problem, code 3 definition Hangbin Liu
2020-10-27 12:33 ` [PATCHv6 net 2/2] IPv6: reply ICMP error if the first fragment don't include all headers Hangbin Liu
2020-10-31 21:12 ` [PATCHv6 net 0/2] IPv6: reply ICMP error if fragment doesn't contain " Jakub Kicinski
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