• Paolo Abeni's avatar
    vxlan: fix oops in dev_fill_metadata_dst · 22f0708a
    Paolo Abeni authored
    Since the commit 0c1d70af ("net: use dst_cache for vxlan device")
    vxlan_fill_metadata_dst() calls vxlan_get_route() passing a NULL
    dst_cache pointer, so the latter should explicitly check for
    valid dst_cache ptr. Unfortunately the commit d71785ff ("net: add
    dst_cache to ovs vxlan lwtunnel") removed said check.
    
    As a result is possible to trigger a null pointer access calling
    vxlan_fill_metadata_dst(), e.g. with:
    
    ovs-vsctl add-br ovs-br0
    ovs-vsctl add-port ovs-br0 vxlan0 -- set interface vxlan0 \
    	type=vxlan options:remote_ip=192.168.1.1 \
    	options:key=1234 options:dst_port=4789 ofport_request=10
    ip address add dev ovs-br0 172.16.1.2/24
    ovs-vsctl set Bridge ovs-br0 ipfix=@i -- --id=@i create IPFIX \
    	targets=\"172.16.1.1:1234\" sampling=1
    iperf -c 172.16.1.1 -u -l 1000 -b 10M -t 1 -p 1234
    
    This commit addresses the issue passing to vxlan_get_route() the
    dst_cache already available into the lwt info processed by
    vxlan_fill_metadata_dst().
    
    Fixes: d71785ff
    
     ("net: add dst_cache to ovs vxlan lwtunnel")
    Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
    Acked-by: default avatarJiri Benc <jbenc@redhat.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    22f0708a