From: John Fastabend <john.fastabend@gmail.com>
Date: Mon, 28 Aug 2017 07:10:45 -0700
Subject: bpf: sockmap add missing rcu_read_(un)lock in smap_data_ready
Patch-mainline: v4.14-rc1
Git-commit: d26e597d87635d90128fafb3f6bb0a14d972d952
References: bsc#1109837
References to psock must be done inside RCU critical section.
Fixes: 174a79ff9515 ("bpf: sockmap with sk redirect support")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
kernel/bpf/sockmap.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
--- a/kernel/bpf/sockmap.c
+++ b/kernel/bpf/sockmap.c
@@ -227,11 +227,14 @@ static void smap_data_ready(struct sock
{
struct smap_psock *psock;
- write_lock_bh(&sk->sk_callback_lock);
+ rcu_read_lock();
psock = smap_psock_sk(sk);
- if (likely(psock))
+ if (likely(psock)) {
+ write_lock_bh(&sk->sk_callback_lock);
strp_data_ready(&psock->strp);
- write_unlock_bh(&sk->sk_callback_lock);
+ write_unlock_bh(&sk->sk_callback_lock);
+ }
+ rcu_read_unlock();
}
static void smap_tx_work(struct work_struct *w)