2020-03-04 10:15:00

by Lorenz Bauer

Subject: [PATCH bpf-next v3 06/12] bpf: sockmap: simplify sock_map_init_proto

We can take advantage of the fact that both callers of
sock_map_init_proto are holding a RCU read lock, and
have verified that psock is valid.

Signed-off-by: Lorenz Bauer <[email protected]>
---
net/core/sock_map.c | 19 ++++---------------
1 file changed, 4 insertions(+), 15 deletions(-)

diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 9898294e119d..83c5082cefd3 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -141,28 +141,17 @@ static void sock_map_unref(struct sock *sk, void *link_raw)
}
}

-static int sock_map_init_proto(struct sock *sk)
+static int sock_map_init_proto(struct sock *sk, struct sk_psock *psock)
{
- struct sk_psock *psock;
struct proto *prot;

sock_owned_by_me(sk);

- rcu_read_lock();
- psock = sk_psock(sk);
- if (unlikely(!psock)) {
- rcu_read_unlock();
- return -EINVAL;
- }
-
prot = tcp_bpf_get_proto(sk, psock);
- if (IS_ERR(prot)) {
- rcu_read_unlock();
+ if (IS_ERR(prot))
return PTR_ERR(prot);
- }

sk_psock_update_proto(sk, psock, prot);
- rcu_read_unlock();
return 0;
}

@@ -241,7 +230,7 @@ static int sock_map_link(struct bpf_map *map, struct sk_psock_progs *progs,
if (msg_parser)
psock_set_prog(&psock->progs.msg_parser, msg_parser);

- ret = sock_map_init_proto(sk);
+ ret = sock_map_init_proto(sk, psock);
if (ret < 0)
goto out_drop;

@@ -286,7 +275,7 @@ static int sock_map_link_no_progs(struct bpf_map *map, struct sock *sk)
if (!psock)
return -ENOMEM;

- ret = sock_map_init_proto(sk);
+ ret = sock_map_init_proto(sk, psock);
if (ret < 0)
sk_psock_put(sk, psock);
return ret;
--
2.20.1

2020-03-05 12:40:44

by Jakub Sitnicki

Subject: Re: [PATCH bpf-next v3 06/12] bpf: sockmap: simplify sock_map_init_proto

On Wed, Mar 04, 2020 at 11:13 AM CET, Lorenz Bauer wrote:
> We can take advantage of the fact that both callers of
> sock_map_init_proto are holding a RCU read lock, and
> have verified that psock is valid.
>
> Signed-off-by: Lorenz Bauer <[email protected]>
> ---

Reviewed-by: Jakub Sitnicki <[email protected]>

[...]

2020-03-06 15:30:10

by John Fastabend

Subject: RE: [PATCH bpf-next v3 06/12] bpf: sockmap: simplify sock_map_init_proto

Lorenz Bauer wrote:
> We can take advantage of the fact that both callers of
> sock_map_init_proto are holding a RCU read lock, and
> have verified that psock is valid.
>
> Signed-off-by: Lorenz Bauer <[email protected]>
> ---
> net/core/sock_map.c | 19 ++++---------------
> 1 file changed, 4 insertions(+), 15 deletions(-)
>

Acked-by: John Fastabend <[email protected]>