[SRU I/F PATCH 1/1] xfrm: fix the if_id check in changelink

[Stefan Bader]

From: Antony Antony <antony.antony at secunet.com>

BugLink: https://bugs.launchpad.net/bugs/1968591

if_id will be always 0, because it was not yet initialized.

Fixes: 8dce43919566 ("xfrm: interface with if_id 0 should return error")
Reported-by: Pavel Machek <pavel at denx.de>
Signed-off-by: Antony Antony <antony.antony at secunet.com>
Signed-off-by: Steffen Klassert <steffen.klassert at secunet.com>

(cherry picked from commit 6d0d95a1c2b07270870e7be16575c513c29af3f1)
Signed-off-by: Stefan Bader <stefan.bader at canonical.com>
---
 net/xfrm/xfrm_interface.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c
index 57448fc519fc..4e3c62d1ad9e 100644
--- a/net/xfrm/xfrm_interface.c
+++ b/net/xfrm/xfrm_interface.c
@@ -673,12 +673,12 @@ static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
 	struct net *net = xi->net;
 	struct xfrm_if_parms p = {};
 
+	xfrmi_netlink_parms(data, &p);
 	if (!p.if_id) {
 		NL_SET_ERR_MSG(extack, "if_id must be non zero");
 		return -EINVAL;
 	}
 
-	xfrmi_netlink_parms(data, &p);
 	xi = xfrmi_locate(net, &p);
 	if (!xi) {
 		xi = netdev_priv(dev);
-- 
2.25.1