[PATCH bpf v3 2/2] bpf, sockmap: sk_prot needs inuse_idx set for proc stats
From: John Fastabend <john.fastabend@gmail.com>
Date: 2021-07-06 16:32:03
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 | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 60decd6420ca..27bdf768aa8c 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c@@ -185,10 +185,19 @@ static void sock_map_unref(struct sock *sk, void *link_raw) static int sock_map_init_proto(struct sock *sk, struct sk_psock *psock) { + int err; +#ifdef CONFIG_PROC_FS + int idx = sk->sk_prot->inuse_idx; +#endif if (!sk->sk_prot->psock_update_sk_prot) return -EINVAL; psock->psock_update_sk_prot = sk->sk_prot->psock_update_sk_prot; - return sk->sk_prot->psock_update_sk_prot(sk, psock, false); + err = sk->sk_prot->psock_update_sk_prot(sk, psock, false); +#ifdef CONFIG_PROC_FS + if (!err) + sk->sk_prot->inuse_idx = idx; +#endif + return err; } static struct sk_psock *sock_map_psock_get_checked(struct sock *sk)
--
2.25.1