[PATCH net] af_key: fix leaks in key_pol_get_resp and dump_sp.

[Jeremy Sowden]

In both functions, if pfkey_xfrm_policy2msg failed we leaked the newly
allocated sk_buff.  Free it on error.

Fixes: 55569ce256ce ("Fix conversion between IPSEC_MODE_xxx and XFRM_MODE_xxx.")
Reported-by: syzbot+4f0529365f7f2208d...@syzkaller.appspotmail.com
Signed-off-by: Jeremy Sowden <jer...@azazel.net>
---
 net/key/af_key.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/net/key/af_key.c b/net/key/af_key.c
index 4af1e1d60b9f..4cca397fd032 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -2442,8 +2442,10 @@ static int key_pol_get_resp(struct sock *sk, struct 
xfrm_policy *xp, const struc
                goto out;
        }
        err = pfkey_xfrm_policy2msg(out_skb, xp, dir);
-       if (err < 0)
-               goto out;
+       if (err < 0) {
+               kfree_skb(out_skb);
+               return err;
+       }
 
        out_hdr = (struct sadb_msg *) out_skb->data;
        out_hdr->sadb_msg_version = hdr->sadb_msg_version;
@@ -2694,8 +2696,10 @@ static int dump_sp(struct xfrm_policy *xp, int dir, int 
count, void *ptr)
                return PTR_ERR(out_skb);
 
        err = pfkey_xfrm_policy2msg(out_skb, xp, dir);
-       if (err < 0)
+       if (err < 0) {
+               kfree_skb(out_skb);
                return err;
+       }
 
        out_hdr = (struct sadb_msg *) out_skb->data;
        out_hdr->sadb_msg_version = pfk->dump.msg_version;
-- 
2.20.1