From: Guillaume Nault gnault@redhat.com
[ Upstream commit a0d56cb911ca301de81735f1d73c2aab424654ba ]
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 Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv6/netfilter/nf_conntrack_reasm.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index cb1b4772dac0..73c29ddcfb95 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; }
skb_dst_drop(skb); @@ -481,12 +485,6 @@ 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) - ret = -EINPROGRESS; - spin_unlock_bh(&fq->q.lock); inet_frag_put(&fq->q); return ret;