5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Tom Hughes <tom@xxxxxxxxxx>
[ Upstream commit 3cd740b985963f874a1a094f1969e998b9d05554 ]
Commit 264640fc2c5f4 ("ipv6: distinguish frag queues by device
for multicast and link-local packets") modified the ipv6 fragment
reassembly logic to distinguish frag queues by device for multicast
and link-local packets but in fact only the main reassembly code
limits the use of the device to those address types and the netfilter
reassembly code uses the device for all packets.
This means that if fragments of a packet arrive on different interfaces
then netfilter will fail to reassemble them and the fragments will be
expired without going any further through the filters.
Fixes: 648700f76b03 ("inet: frags: use rhashtables for reassembly units")
Signed-off-by: Tom Hughes <tom@xxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/ipv6/netfilter/nf_conntrack_reasm.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index 5c47be29b9ee9..2e5b090d7c89f 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -155,6 +155,10 @@ static struct frag_queue *fq_find(struct net *net, __be32 id, u32 user,
};
struct inet_frag_queue *q;
+ if (!(ipv6_addr_type(&hdr->daddr) & (IPV6_ADDR_MULTICAST |
+ IPV6_ADDR_LINKLOCAL)))
+ key.iif = 0;
+
q = inet_frag_find(nf_frag->fqdir, &key);
if (!q)
return NULL;
--
2.43.0
