skb_net returns network namespace from the associated device or socket.
This will be used in the next commit.
I tried to inline it in skbuff.h, but I don't think it's feasible.
It depends on 'net/sock.h' for sock_net() and 'linux/netdevice.h' for
dev_net(), both of which we don't include from 'linux/skbuff.h' (but
both sock.h and netdevice.h include skbuff.h). I though about doing
it as a macro/putting it somewhere else, but we will have
skb_flow_dissect{_xyz} use it in the next commits.
Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
---
include/linux/skbuff.h | 2 ++
net/core/skbuff.c | 16 ++++++++++++++++
2 files changed, 18 insertions(+)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index e8c1d5b97f96..75e1d4d73cca 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1275,6 +1275,8 @@ static inline int skb_flow_dissector_bpf_prog_detach(const union bpf_attr *attr)
}
#endif
+struct net *skb_net(const struct sk_buff *skb);
+
struct bpf_flow_keys;
bool __skb_flow_bpf_dissect(struct bpf_prog *prog,
const struct sk_buff *skb,
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index b413354ee709..d81f3a95fb4e 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -5725,3 +5725,19 @@ void __skb_ext_put(struct skb_ext *ext)
}
EXPORT_SYMBOL(__skb_ext_put);
#endif /* CONFIG_SKB_EXTENSIONS */
+
+/**
+ * skb_net - Return network namespace associated with skb.
+ * @skb: skb
+ *
+ * Returns pointer to struct net or NULL.
+ */
+struct net *skb_net(const struct sk_buff *skb)
+{
+ if (skb->dev)
+ return dev_net(skb->dev);
+ else if (skb->sk)
+ return sock_net(skb->sk);
+ return NULL;
+}
+EXPORT_SYMBOL(skb_net);
--
2.21.0.225.g810b269d1ac-goog
