5.4-stable review patch. If anyone has any objections, please let me know.
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From: David Bauer mail@david-bauer.net
[ Upstream commit f58f45c1e5b92975e91754f5407250085a6ae7cf ]
The VXLAN driver currently does not check if the inner layer2 source-address is valid.
In case source-address snooping/learning is enabled, a entry in the FDB for the invalid address is created with the layer3 address of the tunnel endpoint.
If the frame happens to have a non-unicast address set, all this non-unicast traffic is subsequently not flooded to the tunnel network but sent to the learnt host in the FDB. To make matters worse, this FDB entry does not expire.
Apply the same filtering for packets as it is done for bridges. This not only drops these invalid packets but avoids them from being learnt into the FDB.
Fixes: d342894c5d2f ("vxlan: virtual extensible lan") Suggested-by: Ido Schimmel idosch@nvidia.com Signed-off-by: David Bauer mail@david-bauer.net Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/vxlan.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 8808a6540b190..f70500c85e2a2 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -1605,6 +1605,10 @@ static bool vxlan_set_mac(struct vxlan_dev *vxlan, if (ether_addr_equal(eth_hdr(skb)->h_source, vxlan->dev->dev_addr)) return false;
+ /* Ignore packets from invalid src-address */ + if (!is_valid_ether_addr(eth_hdr(skb)->h_source)) + return false; + /* Get address from the outer IP header */ if (vxlan_get_sk_family(vs) == AF_INET) { saddr.sin.sin_addr.s_addr = ip_hdr(skb)->saddr;