xfrm_user: return error pointer instead of NULL #2

When dump_one_policy() returns an error, e.g. because of a too small
buffer to dump the whole xfrm policy, xfrm_policy_netlink() returns
NULL instead of an error pointer. But its caller expects an error
pointer and therefore continues to operate on a NULL skbuff.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 2 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index dac08e2a5a93..d12b62547ad0 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1548,6 +1548,7 @@ static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb,
 {
         struct xfrm_dump_info info;
         struct sk_buff *skb;
+        int err;
 
         skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
         if (!skb)
@@ -1558,9 +1559,10 @@ static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb,
         info.nlmsg_seq = seq;
         info.nlmsg_flags = 0;
 
-        if (dump_one_policy(xp, dir, 0, &info) < 0) {
+        err = dump_one_policy(xp, dir, 0, &info);
+        if (err) {
                 kfree_skb(skb);
-                return NULL;
+                return ERR_PTR(err);
         }
 
         return skb;