[PATCH 5.7 094/179] geneve: fix an uninitialized value in geneve_changelink()

From: Greg Kroah-Hartman
Date: Mon Jul 27 2020 - 10:22:41 EST


From: Cong Wang <xiyou.wangcong@xxxxxxxxx>

[ Upstream commit 32818c075c54bb0cae44dd6f7ab00b01c52b8372 ]

geneve_nl2info() sets 'df' conditionally, so we have to
initialize it by copying the value from existing geneve
device in geneve_changelink().

Fixes: 56c09de347e4 ("geneve: allow changing DF behavior after creation")
Reported-by: syzbot+7ebc2e088af5e4c0c9fa@xxxxxxxxxxxxxxxxxxxxxxxxx
Cc: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Reviewed-by: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/geneve.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 4661ef865807f..dec52b763d508 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -1615,11 +1615,11 @@ static int geneve_changelink(struct net_device *dev, struct nlattr *tb[],
struct netlink_ext_ack *extack)
{
struct geneve_dev *geneve = netdev_priv(dev);
+ enum ifla_geneve_df df = geneve->df;
struct geneve_sock *gs4, *gs6;
struct ip_tunnel_info info;
bool metadata;
bool use_udp6_rx_checksums;
- enum ifla_geneve_df df;
bool ttl_inherit;
int err;

--
2.25.1