[PATCH bpf, sockmap 2/2] bpf, sockmap: sk_prot needs inuse_idx set for proc stats
From: John Fastabend <john.fastabend@gmail.com>
Date: 2021-06-30 21:54:20
Also in:
bpf
Subsystem:
bpf [l7 framework] (sockmap), networking [general], networking [sockets], the rest · Maintainers:
John Fastabend, Jakub Sitnicki, Jiayuan Chen, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Kuniyuki Iwashima, Willem de Bruijn, Linus Torvalds
Proc socket stats use sk_prot->inuse_idx value to record inuse sock stats.
We currently do not set this correctly from sockmap side. The result is
reading sock stats '/proc/net/sockstat' gives incorrect values. The
socket counter is incremented correctly, but because we don't set the
counter correctly when we replace sk_prot we may omit the decrement.
Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
---
net/core/sock_map.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 60decd6420ca..29e7bae65db5 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c@@ -221,7 +221,7 @@ static int sock_map_link(struct bpf_map *map, struct sock *sk) struct bpf_prog *skb_verdict = NULL; struct bpf_prog *msg_parser = NULL; struct sk_psock *psock; - int ret; + int ret, idx; /* Only sockets we can redirect into/from in BPF need to hold * refs to parser/verdict progs and have their sk_data_ready
@@ -293,9 +293,11 @@ static int sock_map_link(struct bpf_map *map, struct sock *sk) if (msg_parser) psock_set_prog(&psock->progs.msg_parser, msg_parser); + idx = sk->sk_prot->inuse_idx; ret = sock_map_init_proto(sk, psock); if (ret < 0) goto out_drop; + sk->sk_prot->inuse_idx = idx; write_lock_bh(&sk->sk_callback_lock); if (stream_parser && stream_verdict && !psock->saved_data_ready) {
--
2.25.1