Use rcu_assign_pointer, and tmp variables for freeing on the error
path without accessing net->xfrm.state_by*.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
---
 net/xfrm/xfrm_state.c | 32 ++++++++++++++++++++------------
 1 file changed, 20 insertions(+), 12 deletions(-)

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 7a68c594ce37..e9bf160a30f8 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -3258,6 +3258,7 @@ EXPORT_SYMBOL(xfrm_init_state);
 
 int __net_init xfrm_state_init(struct net *net)
 {
+	struct hlist_head *ndst, *nsrc, *nspi, *nseq;
 	unsigned int sz;
 
 	if (net_eq(net, &init_net))
@@ -3268,18 +3269,25 @@ int __net_init xfrm_state_init(struct net *net)
 
 	sz = sizeof(struct hlist_head) * 8;
 
-	net->xfrm.state_bydst = xfrm_hash_alloc(sz);
-	if (!net->xfrm.state_bydst)
+	ndst = xfrm_hash_alloc(sz);
+	if (!ndst)
 		goto out_bydst;
-	net->xfrm.state_bysrc = xfrm_hash_alloc(sz);
-	if (!net->xfrm.state_bysrc)
+	rcu_assign_pointer(net->xfrm.state_bydst, ndst);
+
+	nsrc = xfrm_hash_alloc(sz);
+	if (!nsrc)
 		goto out_bysrc;
-	net->xfrm.state_byspi = xfrm_hash_alloc(sz);
-	if (!net->xfrm.state_byspi)
+	rcu_assign_pointer(net->xfrm.state_bysrc, nsrc);
+
+	nspi = xfrm_hash_alloc(sz);
+	if (!nspi)
 		goto out_byspi;
-	net->xfrm.state_byseq = xfrm_hash_alloc(sz);
-	if (!net->xfrm.state_byseq)
+	rcu_assign_pointer(net->xfrm.state_byspi, nspi);
+
+	nseq = xfrm_hash_alloc(sz);
+	if (!nseq)
 		goto out_byseq;
+	rcu_assign_pointer(net->xfrm.state_byseq, nseq);
 
 	net->xfrm.state_cache_input = alloc_percpu(struct hlist_head);
 	if (!net->xfrm.state_cache_input)
@@ -3295,13 +3303,13 @@ int __net_init xfrm_state_init(struct net *net)
 	return 0;
 
 out_state_cache_input:
-	xfrm_hash_free(net->xfrm.state_byseq, sz);
+	xfrm_hash_free(nseq, sz);
 out_byseq:
-	xfrm_hash_free(net->xfrm.state_byspi, sz);
+	xfrm_hash_free(nspi, sz);
 out_byspi:
-	xfrm_hash_free(net->xfrm.state_bysrc, sz);
+	xfrm_hash_free(nsrc, sz);
 out_bysrc:
-	xfrm_hash_free(net->xfrm.state_bydst, sz);
+	xfrm_hash_free(ndst, sz);
 out_bydst:
 	return -ENOMEM;
 }
-- 
2.51.2