[PATCH 3.2 131/153] skbuff: Fix not waking applications when errors are enqueued

[Ben Hutchings]

3.2.102-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Vinicius Costa Gomes <vinicius.gomes@xxxxxxxxx>

commit 6e5d58fdc9bedd0255a8781b258f10bbdc63e975 upstream.

When errors are enqueued to the error queue via sock_queue_err_skb()
function, it is possible that the waiting application is not notified.

Calling 'sk->sk_data_ready()' would not notify applications that
selected only POLLERR events in poll() (for example).

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Randy E. Witt <randy.e.witt@xxxxxxxxx>
Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
[bwh: Backported to 3.2: sk_data_ready() operation takes a length parameter.
 Delete the local variable we used for that.]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 net/core/skbuff.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3093,8 +3093,6 @@ static void sock_rmem_free(struct sk_buf
  */
 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
 {
-	int len = skb->len;
-
 	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
 	    (unsigned)sk->sk_rcvbuf)
 		return -ENOMEM;
@@ -3109,7 +3107,7 @@ int sock_queue_err_skb(struct sock *sk,
 
 	skb_queue_tail(&sk->sk_error_queue, skb);
 	if (!sock_flag(sk, SOCK_DEAD))
-		sk->sk_data_ready(sk, len);
+		sk->sk_error_report(sk);
 	return 0;
 }
 EXPORT_SYMBOL(sock_queue_err_skb);