From: Doron Roberts-Kedes <doronrk@fb.com>
Date: Wed, 18 Jul 2018 23:22:27 +0000 (-0700)
Subject: tls: check RCV_SHUTDOWN in tls_wait_data
X-Git-Tag: v4.18-rc7~23^2~28
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=fcf4793e278edede8fcd748198d12128037e526c;p=linux.git

tls: check RCV_SHUTDOWN in tls_wait_data

The current code does not check sk->sk_shutdown & RCV_SHUTDOWN.
tls_sw_recvmsg may return a positive value in the case where bytes have
already been copied when the socket is shutdown. sk->sk_err has been
cleared, causing the tls_wait_data to hang forever on a subsequent
invocation. Checking sk->sk_shutdown & RCV_SHUTDOWN, as in tcp_recvmsg,
fixes this problem.

Fixes: c46234ebb4d1 ("tls: RX path for ktls")
Acked-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: Doron Roberts-Kedes <doronrk@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 4618f1c31137..1f3d9789af30 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -646,6 +646,9 @@ static struct sk_buff *tls_wait_data(struct sock *sk, int flags,
 			return NULL;
 		}
 
+		if (sk->sk_shutdown & RCV_SHUTDOWN)
+			return NULL;
+
 		if (sock_flag(sk, SOCK_DONE))
 			return NULL;