From: Alex Gartrell <agartrell@fb.com>
Date: Fri, 26 Dec 2014 07:22:49 +0000 (-0800)
Subject: tun: return proper error code from tun_do_read
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=957f094f221f81e457133b1f4c4d95ffa49ff731;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

tun: return proper error code from tun_do_read

Instead of -1 with EAGAIN, read on a O_NONBLOCK tun fd will return 0.  This
fixes this by properly returning the error code from __skb_recv_datagram.

Signed-off-by: Alex Gartrell <agartrell@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index df5e94871844..c0df872f5b8c 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1380,7 +1380,7 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
 	skb = __skb_recv_datagram(tfile->socket.sk, noblock ? MSG_DONTWAIT : 0,
 				  &peeked, &off, &err);
 	if (!skb)
-		return 0;
+		return err;
 
 	ret = tun_put_user(tun, tfile, skb, to);
 	if (unlikely(ret < 0))