xfrm_user: return error pointer instead of NULL #2

[ Upstream commit c25463722509fef0ed630b271576a8c9a70236f3 ]

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>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index a092828..1221b77 100644 (file)
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1531,6 +1531,7 @@ 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)
@@ -1541,9 +1542,10 @@ 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;