From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 6 Nov 2019 08:13:49 +0100
Subject: xfrm: Fix memleak on xfrm state destroy
Git-commit: 86c6739eda7d2a03f2db30cbee67a5fb81afa8ba
Patch-mainline: 5.4-rc8
References: bnc#1151927 5.3.15 bsc#1158775

We leak the page that we use to create skb page fragments
when destroying the xfrm_state. Fix this by dropping a
page reference if a page was assigned to the xfrm_state.

Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible")
Reported-by: JD <jdtxs00@gmail.com>
Reported-by: Paul Wouters <paul@nohats.ca>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 net/xfrm/xfrm_state.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -495,6 +495,8 @@ static void ___xfrm_state_destroy(struct
 		x->type->destructor(x);
 		xfrm_put_type(x->type);
 	}
+	if (x->xfrag.page)
+		put_page(x->xfrag.page);
 	xfrm_dev_state_free(x);
 	security_xfrm_state_free(x);
 	xfrm_state_free(x);