diff options
author | Guillaume Nault <gnault@redhat.com> | 2019-06-06 18:04:00 +0200 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2019-06-07 14:49:01 +0200 |
commit | 8a3dca632538c550930ce8bafa8c906b130d35cf (patch) | |
tree | 03c6a9baaa651973f12ee993491eb295023ee42c | |
parent | netfilter: ipv6: nf_defrag: fix leakage of unqueued fragments (diff) | |
download | linux-8a3dca632538c550930ce8bafa8c906b130d35cf.tar.xz linux-8a3dca632538c550930ce8bafa8c906b130d35cf.zip |
netfilter: ipv6: nf_defrag: accept duplicate fragments again
When fixing the skb leak introduced by the conversion to rbtree, I
forgot about the special case of duplicate fragments. The condition
under the 'insert_error' label isn't effective anymore as
nf_ct_frg6_gather() doesn't override the returned value anymore. So
duplicate fragments now get NF_DROP verdict.
To accept duplicate fragments again, handle them specially as soon as
inet_frag_queue_insert() reports them. Return -EINPROGRESS which will
translate to NF_STOLEN verdict, like any accepted fragment. However,
such packets don't carry any new information and aren't queued, so we
just drop them immediately.
Fixes: a0d56cb911ca ("netfilter: ipv6: nf_defrag: fix leakage of unqueued fragments")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
-rw-r--r-- | net/ipv6/netfilter/nf_conntrack_reasm.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index 5b3f65e29b6f..8951de8b568f 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -265,8 +265,14 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb, prev = fq->q.fragments_tail; err = inet_frag_queue_insert(&fq->q, skb, offset, end); - if (err) + if (err) { + if (err == IPFRAG_DUP) { + /* No error for duplicates, pretend they got queued. */ + kfree_skb(skb); + return -EINPROGRESS; + } goto insert_error; + } if (dev) fq->iif = dev->ifindex; @@ -304,8 +310,6 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb, return -EINPROGRESS; insert_error: - if (err == IPFRAG_DUP) - goto err; inet_frag_kill(&fq->q); err: skb_dst_drop(skb); |