[ Upstream commit 5fa2ca7c4a3fc176f31b495e1a704862d8188b53 ]
The tcp_bpf_wait_data() routine needs to check timeo != 0 before
calling sk_wait_event() otherwise we may see unexpected stalls
on receiver.
Arika did all the leg work here I just formatted, posted and ran
a few tests.
Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface")
Reported-by: Arika Chen <eaglesora@xxxxxxxxx>
Suggested-by: Arika Chen <eaglesora@xxxxxxxxx>
Signed-off-by: John Fastabend <john.fastabend@xxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/ipv4/tcp_bpf.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c
index 4a619c85daed..3d1e15401384 100644
--- a/net/ipv4/tcp_bpf.c
+++ b/net/ipv4/tcp_bpf.c
@@ -27,7 +27,10 @@ static int tcp_bpf_wait_data(struct sock *sk, struct sk_psock *psock,
int flags, long timeo, int *err)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
- int ret;
+ int ret = 0;
+
+ if (!timeo)
+ return ret;
add_wait_queue(sk_sleep(sk), &wait);
sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
--
2.20.1
