[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>

1 files changed, 11 insertions, 12 deletions

diff --git a/net/core/filter.c b/net/core/filter.c
index 2be1830d3c35..54dddc92452d 100644
--- 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)