[net-next,2/2] skbuff: Fix not waking applications when errors are enqueued

Message ID 20180313203519.8638-3-vinicius.gomes@intel.com
State Superseded
Delegated to: David Miller
Headers show
Series
  • skbuff: Fix applications not being woken for errors
Related show

Commit Message

Vinicius Costa Gomes March 13, 2018, 8:35 p.m.
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).

Reported-by: Randy E. Witt <randy.e.witt@intel.com>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
---
 net/core/skbuff.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Eric Dumazet March 14, 2018, 4:40 p.m. | #1
On 03/13/2018 01:35 PM, Vinicius Costa Gomes wrote:
> 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).
> 
> Reported-by: Randy E. Witt <randy.e.witt@intel.com>
> Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
> ---
>   net/core/skbuff.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/core/skbuff.c b/net/core/skbuff.c
> index 715c13495ba6..6def3534f509 100644
> --- a/net/core/skbuff.c
> +++ b/net/core/skbuff.c
> @@ -4181,7 +4181,7 @@ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
>   
>   	skb_queue_tail(&sk->sk_error_queue, skb);
>   	if (!sock_flag(sk, SOCK_DEAD))
> -		sk->sk_data_ready(sk);
> +		sk->sk_error_report(sk);
>   	return 0;
>   }
>   EXPORT_SYMBOL(sock_queue_err_skb);
> 

Reviewed-by: Eric Dumazet <edumazet@google.com>

Given this bug has been there forever, there is probably no rush to get 
the fix in 4.16, but this looks safe enough IMO.

Patch

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 715c13495ba6..6def3534f509 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -4181,7 +4181,7 @@  int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
 
 	skb_queue_tail(&sk->sk_error_queue, skb);
 	if (!sock_flag(sk, SOCK_DEAD))
-		sk->sk_data_ready(sk);
+		sk->sk_error_report(sk);
 	return 0;
 }
 EXPORT_SYMBOL(sock_queue_err_skb);