path: root/net
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authorGuillaume Nault <gnault@redhat.com>2019-06-02 15:13:47 +0200
committerPablo Neira Ayuso <pablo@netfilter.org>2019-06-04 15:25:51 +0200
commita0d56cb911ca301de81735f1d73c2aab424654ba (patch)
tree8e3c9b1dee210ccf4c62fe7549f06e69693c8197 /net
parent5142967ab524eb8e5c1f6122e46e2df81bae178b (diff)
netfilter: ipv6: nf_defrag: fix leakage of unqueued fragments
With commit 997dd9647164 ("net: IP6 defrag: use rbtrees in nf_conntrack_reasm.c"), nf_ct_frag6_reasm() is now called from nf_ct_frag6_queue(). With this change, nf_ct_frag6_queue() can fail after the skb has been added to the fragment queue and nf_ct_frag6_gather() was adapted to handle this case. But nf_ct_frag6_queue() can still fail before the fragment has been queued. nf_ct_frag6_gather() can't handle this case anymore, because it has no way to know if nf_ct_frag6_queue() queued the fragment before failing. If it didn't, the skb is lost as the error code is overwritten with -EINPROGRESS. Fix this by setting -EINPROGRESS directly in nf_ct_frag6_queue(), so that nf_ct_frag6_gather() can propagate the error as is. Fixes: 997dd9647164 ("net: IP6 defrag: use rbtrees in nf_conntrack_reasm.c") Signed-off-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
1 files changed, 5 insertions, 7 deletions
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index 3de0e9b0a482..5b3f65e29b6f 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -293,7 +293,11 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
skb->_skb_refdst = 0UL;
err = nf_ct_frag6_reasm(fq, skb, prev, dev);
skb->_skb_refdst = orefdst;
- return err;
+ /* After queue has assumed skb ownership, only 0 or
+ * -EINPROGRESS must be returned.
+ */
+ return err ? -EINPROGRESS : 0;
@@ -480,12 +484,6 @@ int nf_ct_frag6_gather(struct net *net, struct sk_buff *skb, u32 user)
ret = 0;
- /* after queue has assumed skb ownership, only 0 or -EINPROGRESS
- * must be returned.
- */
- if (ret)
return ret;