diff options
| author | John Fastabend <john.fastabend@gmail.com> | 2017-07-17 09:28:56 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-07-17 09:48:06 -0700 |
| commit | 546ac1ffb70d25b56c1126940e5ec639c4dd7413 (patch) | |
| tree | ee72376133d162b6bacd60cc6c061458a76be88c /kernel/bpf/verifier.c | |
| parent | 5acaee0a8964c9bab7775ab8bedcd1f66a2a1011 (diff) | |
bpf: add devmap, a map for storing net device references
Device map (devmap) is a BPF map, primarily useful for networking
applications, that uses a key to lookup a reference to a netdevice.
The map provides a clean way for BPF programs to build virtual port
to physical port maps. Additionally, it provides a scoping function
for the redirect action itself allowing multiple optimizations. Future
patches will leverage the map to provide batching at the XDP layer.
Another optimization/feature, that is not yet implemented, would be
to support multiple netdevices per key to support efficient multicast
and broadcast support.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel/bpf/verifier.c')
| -rw-r--r-- | kernel/bpf/verifier.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 6a86723c5b64..4016774d5cca 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1276,6 +1276,14 @@ static int check_map_func_compatibility(struct bpf_map *map, int func_id) func_id != BPF_FUNC_current_task_under_cgroup) goto error; break; + /* devmap returns a pointer to a live net_device ifindex that we cannot + * allow to be modified from bpf side. So do not allow lookup elements + * for now. + */ + case BPF_MAP_TYPE_DEVMAP: + if (func_id == BPF_FUNC_map_lookup_elem) + goto error; + break; case BPF_MAP_TYPE_ARRAY_OF_MAPS: case BPF_MAP_TYPE_HASH_OF_MAPS: if (func_id != BPF_FUNC_map_lookup_elem) |