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Commit 6aafeef0 authored by Jiri Pirko's avatar Jiri Pirko Committed by David S. Miller
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netfilter: push reasm skb through instead of original frag skbs



Pushing original fragments through causes several problems. For example
for matching, frags may not be matched correctly. Take following
example:

<example>
On HOSTA do:
ip6tables -I INPUT -p icmpv6 -j DROP
ip6tables -I INPUT -p icmpv6 -m icmp6 --icmpv6-type 128 -j ACCEPT

and on HOSTB you do:
ping6 HOSTA -s2000    (MTU is 1500)

Incoming echo requests will be filtered out on HOSTA. This issue does
not occur with smaller packets than MTU (where fragmentation does not happen)
</example>

As was discussed previously, the only correct solution seems to be to use
reassembled skb instead of separete frags. Doing this has positive side
effects in reducing sk_buff by one pointer (nfct_reasm) and also the reams
dances in ipvs and conntrack can be removed.

Future plan is to remove net/ipv6/netfilter/nf_conntrack_reasm.c
entirely and use code in net/ipv6/reassembly.c instead.

Signed-off-by: default avatarJiri Pirko <jiri@resnulli.us>
Acked-by: default avatarJulian Anastasov <ja@ssi.bg>
Signed-off-by: default avatarMarcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9037c357
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