From: Stanislav Fomichev <sdf@google.com>
To: netdev@vger.kernel.org, bpf@vger.kernel.org
Cc: davem@davemloft.net, ast@kernel.org, daniel@iogearbox.net,
simon.horman@netronome.com, willemb@google.com,
peterpenkov96@gmail.com, Stanislav Fomichev <sdf@google.com>
Subject: [PATCH bpf-next v6 4/9] flow_dissector: handle no-skb use case
Date: Mon, 22 Apr 2019 08:55:47 -0700 [thread overview]
Message-ID: <20190422155552.222910-5-sdf@google.com> (raw)
In-Reply-To: <20190422155552.222910-1-sdf@google.com>
When called without skb, gather all required data from the
__skb_flow_dissect's arguments and use recently introduces
no-skb mode of bpf flow dissector.
Note: WARN_ON_ONCE(!net) will now trigger for eth_get_headlen users.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
include/linux/skbuff.h | 5 ----
net/core/flow_dissector.c | 52 +++++++++++++++++++--------------------
2 files changed, 25 insertions(+), 32 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index ee7d1a85f624..61e2e4678f57 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1279,11 +1279,6 @@ struct bpf_flow_dissector;
bool bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
__be16 proto, int nhoff, int hlen);
-struct bpf_flow_keys;
-bool __skb_flow_bpf_dissect(struct bpf_prog *prog,
- const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- struct bpf_flow_keys *flow_keys);
bool __skb_flow_dissect(const struct net *net,
const struct sk_buff *skb,
struct flow_dissector *flow_dissector,
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index f32c7e737fc6..fac712cee9d5 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -683,22 +683,6 @@ static void __skb_flow_bpf_to_target(const struct bpf_flow_keys *flow_keys,
}
}
-bool __skb_flow_bpf_dissect(struct bpf_prog *prog,
- const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- struct bpf_flow_keys *flow_keys)
-{
- struct bpf_flow_dissector ctx = {
- .flow_keys = flow_keys,
- .skb = skb,
- .data = skb->data,
- .data_end = skb->data + skb_headlen(skb),
- };
-
- return bpf_flow_dissect(prog, &ctx, skb->protocol,
- skb_network_offset(skb), skb_headlen(skb));
-}
-
bool bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
__be16 proto, int nhoff, int hlen)
{
@@ -753,6 +737,7 @@ bool __skb_flow_dissect(const struct net *net,
struct flow_dissector_key_icmp *key_icmp;
struct flow_dissector_key_tags *key_tags;
struct flow_dissector_key_vlan *key_vlan;
+ struct bpf_prog *attached = NULL;
enum flow_dissect_ret fdret;
enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
int num_hdrs = 0;
@@ -795,26 +780,39 @@ bool __skb_flow_dissect(const struct net *net,
target_container);
if (skb) {
- struct bpf_flow_keys flow_keys;
- struct bpf_prog *attached = NULL;
-
- rcu_read_lock();
if (!net) {
if (skb->dev)
net = dev_net(skb->dev);
else if (skb->sk)
net = sock_net(skb->sk);
- else
- WARN_ON_ONCE(1);
}
+ }
- if (net)
- attached = rcu_dereference(net->flow_dissector_prog);
+ WARN_ON_ONCE(!net);
+ if (net) {
+ rcu_read_lock();
+ attached = rcu_dereference(net->flow_dissector_prog);
if (attached) {
- ret = __skb_flow_bpf_dissect(attached, skb,
- flow_dissector,
- &flow_keys);
+ struct bpf_flow_keys flow_keys;
+ struct bpf_flow_dissector ctx = {
+ .flow_keys = &flow_keys,
+ .data = data,
+ .data_end = data + hlen,
+ };
+ __be16 n_proto = proto;
+
+ if (skb) {
+ ctx.skb = skb;
+ /* we can't use 'proto' in the skb case
+ * because it might be set to skb->vlan_proto
+ * which has been pulled from the data
+ */
+ n_proto = skb->protocol;
+ }
+
+ ret = bpf_flow_dissect(attached, &ctx, n_proto, nhoff,
+ hlen);
__skb_flow_bpf_to_target(&flow_keys, flow_dissector,
target_container);
rcu_read_unlock();
--
2.21.0.593.g511ec345e18-goog
next prev parent reply other threads:[~2019-04-22 15:56 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-22 15:55 [PATCH bpf-next v6 0/9] net: flow_dissector: trigger BPF hook when called from eth_get_headlen Stanislav Fomichev
2019-04-22 15:55 ` [PATCH bpf-next v6 1/9] flow_dissector: switch kernel context to struct bpf_flow_dissector Stanislav Fomichev
2019-04-22 15:55 ` [PATCH bpf-next v6 2/9] bpf: when doing BPF_PROG_TEST_RUN for flow dissector use no-skb mode Stanislav Fomichev
2019-04-22 15:55 ` [PATCH bpf-next v6 3/9] net: plumb network namespace into __skb_flow_dissect Stanislav Fomichev
2019-04-22 18:08 ` Saeed Mahameed
2019-04-22 18:53 ` Stanislav Fomichev
2019-04-22 15:55 ` Stanislav Fomichev [this message]
2019-04-22 15:55 ` [PATCH bpf-next v6 5/9] net: pass net_device argument to the eth_get_headlen Stanislav Fomichev
2019-04-22 15:55 ` [PATCH bpf-next v6 6/9] selftests/bpf: add flow dissector bpf_skb_load_bytes helper test Stanislav Fomichev
2019-04-22 15:55 ` [PATCH bpf-next v6 7/9] selftests/bpf: run flow dissector tests in skb-less mode Stanislav Fomichev
2019-04-22 15:55 ` [PATCH bpf-next v6 8/9] selftests/bpf: properly return error from bpf_flow_load Stanislav Fomichev
2019-04-22 15:55 ` [PATCH bpf-next v6 9/9] bpf/flow_dissector: don't adjust nhoff by ETH_HLEN in BPF_PROG_TEST_RUN Stanislav Fomichev
2019-04-23 4:15 ` [PATCH bpf-next v6 0/9] net: flow_dissector: trigger BPF hook when called from eth_get_headlen Alexei Starovoitov
2019-04-23 16:00 ` Eric Dumazet
2019-04-23 16:19 ` Eric Dumazet
2019-04-23 16:24 ` Willem de Bruijn
2019-04-23 16:38 ` Daniel Borkmann
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190422155552.222910-5-sdf@google.com \
--to=sdf@google.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=netdev@vger.kernel.org \
--cc=peterpenkov96@gmail.com \
--cc=simon.horman@netronome.com \
--cc=willemb@google.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).