[PATCH net-next] ipv6: set msg_control_is_user in do_ipv6_getsockopt

[Christoph Hellwig]

While do_ipv6_getsockopt does not call the high-level recvmsg helper,
the msghdr eventually ends up being passed to put_cmsg anyway, and thus
needs msg_control_is_user set to the proper value.

Fixes: 1f466e1f15cf ("net: cleanly handle kernel vs user buffers for 
->msg_control")
Reported-by: Eric Dumazet <eric.duma...@gmail.com>
Signed-off-by: Christoph Hellwig <h...@lst.de>
---
 net/ipv6/ipv6_sockglue.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 18d05403d3b52..a0e50cc57e545 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -1075,6 +1075,7 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, 
int optname,
                msg.msg_control = optval;
                msg.msg_controllen = len;
                msg.msg_flags = flags;
+               msg.msg_control_is_user = true;
 
                lock_sock(sk);
                skb = np->pktoptions;
-- 
2.26.2