[PATCH 2/3] xfrm: unbreak xfrm_sk_policy_lookup

[Steffen Klassert]

From: Florian Westphal <f...@strlen.de>

if we succeed grabbing the refcount, then
  if (err && !xfrm_pol_hold_rcu)

will evaluate to false so this hits last else branch which then
sets policy to ERR_PTR(0).

Fixes: ae33786f73a7ce ("xfrm: policy: only use rcu in xfrm_sk_policy_lookup")
Reported-by: Nicolas Dichtel <nicolas.dich...@6wind.com>
Tested-by: Nicolas Dichtel <nicolas.dich...@6wind.com>
Signed-off-by: Florian Westphal <f...@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klass...@secunet.com>
---
 net/xfrm/xfrm_policy.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index fd69866..5bf7e1bf 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1268,12 +1268,14 @@ static struct xfrm_policy *xfrm_sk_policy_lookup(const 
struct sock *sk, int dir,
                        err = security_xfrm_policy_lookup(pol->security,
                                                      fl->flowi_secid,
                                                      policy_to_flow_dir(dir));
-                       if (!err && !xfrm_pol_hold_rcu(pol))
-                               goto again;
-                       else if (err == -ESRCH)
+                       if (!err) {
+                               if (!xfrm_pol_hold_rcu(pol))
+                                       goto again;
+                       } else if (err == -ESRCH) {
                                pol = NULL;
-                       else
+                       } else {
                                pol = ERR_PTR(err);
+                       }
                } else
                        pol = NULL;
        }
-- 
1.9.1