[NET]: Cleanup the error path in sk_attach_filter

The sk_filter_uncharge is called for error handling and
for releasing the former filter, but this will have to
be done in a bit different manner, so cleanup the error
path a bit.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/filter.c b/net/core/filter.c
index 2be1830d3c35183d033ecc9108f98ae58d204c0a..54dddc92452dc226f2ba6232cdc43f4a89a9cb9b 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -398,7 +398,7 @@ int sk_chk_filter(struct sock_filter *filter, int flen)
  */
 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
 {
-       struct sk_filter *fp;
+       struct sk_filter *fp, *old_fp;
        unsigned int fsize = sizeof(struct sock_filter) * fprog->len;
        int err;
 
@@ -418,19 +418,18 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
        fp->len = fprog->len;
 
        err = sk_chk_filter(fp->insns, fp->len);
-       if (!err) {
-               struct sk_filter *old_fp;
-
-               rcu_read_lock_bh();
-               old_fp = rcu_dereference(sk->sk_filter);
-               rcu_assign_pointer(sk->sk_filter, fp);
-               rcu_read_unlock_bh();
-               fp = old_fp;
+       if (err) {
+               sk_filter_uncharge(sk, fp);
+               return err;
        }
 
-       if (fp)
-               sk_filter_uncharge(sk, fp);
-       return err;
+       rcu_read_lock_bh();
+       old_fp = rcu_dereference(sk->sk_filter);
+       rcu_assign_pointer(sk->sk_filter, fp);
+       rcu_read_unlock_bh();
+
+       sk_filter_uncharge(sk, old_fp);
+       return 0;
 }
 
 int sk_detach_filter(struct sock *sk)