connector: bump skb->users before callback invocation

Dmitry reports memleak with syskaller program.
Problem is that connector bumps skb usecount but might not invoke callback.

So move skb_get to where we invoke the callback.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/connector/connector.c b/drivers/connector/connector.c
index d7373ca69c9947a83dd8a1d67b77c7fc9e77209e..25693b0453714ca8bb1e610fdda0786a1fc3798e 100644 (file)
--- a/drivers/connector/connector.c
+++ b/drivers/connector/connector.c
@@ -179,26 +179,21 @@ static int cn_call_callback(struct sk_buff *skb)
  *
  * It checks skb, netlink header and msg sizes, and calls callback helper.
  */
-static void cn_rx_skb(struct sk_buff *__skb)
+static void cn_rx_skb(struct sk_buff *skb)
 {
        struct nlmsghdr *nlh;
-       struct sk_buff *skb;
        int len, err;
 
-       skb = skb_get(__skb);
-
        if (skb->len >= NLMSG_HDRLEN) {
                nlh = nlmsg_hdr(skb);
                len = nlmsg_len(nlh);
 
                if (len < (int)sizeof(struct cn_msg) ||
                    skb->len < nlh->nlmsg_len ||
-                   len > CONNECTOR_MAX_MSG_SIZE) {
-                       kfree_skb(skb);
+                   len > CONNECTOR_MAX_MSG_SIZE)
                        return;
-               }
 
-               err = cn_call_callback(skb);
+               err = cn_call_callback(skb_get(skb));
                if (err < 0)
                        kfree_skb(skb);
        }