ipv6: reassembly: use seperate reassembly queues for conntrack and local delivery

commit 0b5ccb2ee250136dd7385b1c7da28417d0d4d32d upstream.

Currently the same reassembly queue might be used for packets reassembled
by conntrack in different positions in the stack (PREROUTING/LOCAL_OUT),
as well as local delivery. This can cause "packet jumps" when the fragment
completing a reassembled packet is queued from a different position in the
stack than the previous ones.

Add a "user" identifier to the reassembly queue key to seperate the queues
of each caller, similar to what we do for IPv4.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 19 insertions, 6 deletions

diff --git a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
index 5f2ec208a8c3..c0a82fe78321 100644
--- a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
@@ -187,6 +187,16 @@ out:
 	return nf_conntrack_confirm(skb);
 }
 
+static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
+						struct sk_buff *skb)
+{
+	if (hooknum == NF_INET_PRE_ROUTING)
+		return IP6_DEFRAG_CONNTRACK_IN;
+	else
+		return IP6_DEFRAG_CONNTRACK_OUT;
+
+}
+
 static unsigned int ipv6_defrag(unsigned int hooknum,
 				struct sk_buff *skb,
 				const struct net_device *in,
@@ -199,8 +209,7 @@ static unsigned int ipv6_defrag(unsigned int hooknum,
 	if (skb->nfct)
 		return NF_ACCEPT;
 
-	reasm = nf_ct_frag6_gather(skb);
-
+	reasm = nf_ct_frag6_gather(skb, nf_ct6_defrag_user(hooknum, skb));
 	/* queued */
 	if (reasm == NULL)
 		return NF_STOLEN;
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index f3aba255ad9f..4b6a539cb87a 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -170,13 +170,14 @@ out:
 /* Creation primitives. */
 
 static __inline__ struct nf_ct_frag6_queue *
-fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst)
+fq_find(__be32 id, u32 user, struct in6_addr *src, struct in6_addr *dst)
 {
 	struct inet_frag_queue *q;
 	struct ip6_create_arg arg;
 	unsigned int hash;
 
 	arg.id = id;
+	arg.user = user;
 	arg.src = src;
 	arg.dst = dst;
 
@@ -561,7 +562,7 @@ find_prev_fhdr(struct sk_buff *skb, u8 *prevhdrp, int *prevhoff, int *fhoff)
 	return 0;
 }
 
-struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb)
+struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb, u32 user)
 {
 	struct sk_buff *clone;
 	struct net_device *dev = skb->dev;
@@ -607,7 +608,7 @@ struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb)
 	if (atomic_read(&nf_init_frags.mem) > nf_init_frags.high_thresh)
 		nf_ct_frag6_evictor();
 
-	fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr);
+	fq = fq_find(fhdr->identification, user, &hdr->saddr, &hdr->daddr);
 	if (fq == NULL) {
 		pr_debug("Can't find and can't create new queue\n");
 		goto ret_orig;
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index da5bd0ed83df..4d18699f93fd 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -72,6 +72,7 @@ struct frag_queue
 	struct inet_frag_queue	q;
 
 	__be32			id;		/* fragment id		*/
+	u32			user;
 	struct in6_addr		saddr;
 	struct in6_addr		daddr;
 
@@ -141,7 +142,7 @@ int ip6_frag_match(struct inet_frag_queue *q, void *a)
 	struct ip6_create_arg *arg = a;
 
 	fq = container_of(q, struct frag_queue, q);
-	return (fq->id == arg->id &&
+	return (fq->id == arg->id && fq->user == arg->user &&
 			ipv6_addr_equal(&fq->saddr, arg->src) &&
 			ipv6_addr_equal(&fq->daddr, arg->dst));
 }
@@ -163,6 +164,7 @@ void ip6_frag_init(struct inet_frag_queue *q, void *a)
 	struct ip6_create_arg *arg = a;
 
 	fq->id = arg->id;
+	fq->user = arg->user;
 	ipv6_addr_copy(&fq->saddr, arg->src);
 	ipv6_addr_copy(&fq->daddr, arg->dst);
 }
@@ -244,6 +246,7 @@ fq_find(struct net *net, __be32 id, struct in6_addr *src, struct in6_addr *dst,
 	unsigned int hash;
 
 	arg.id = id;
+	arg.user = IP6_DEFRAG_LOCAL_DELIVER;
 	arg.src = src;
 	arg.dst = dst;