Re: [PATCH] net: inet: diag: Fix an error handling

2016-09-12 Thread Christophe JAILLET 

Le 12/09/2016 à 16:35, David Ahern a écrit :

On 9/12/16 12:02 AM, Christophe JAILLET wrote:

diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index abfbe492ebfe..795af25cf84c 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -1134,7 +1134,6 @@ int inet_diag_handler_get_info(struct sk_buff *skb, 
struct sock *sk)
  
  	handler = inet_diag_lock_handler(sk->sk_protocol);

if (IS_ERR(handler)) {
-   inet_diag_unlock_handler(handler);
nlmsg_cancel(skb, nlh);
return PTR_ERR(handler);
}


That call is needed. inet_diag_unlock_handler does not operate on the input arg 
but a global mutex. Perhaps a better patch is to change 
inet_diag_unlock_handler() to a void.

This is obvious. Sorry for the noise.

CJ

Re: [PATCH] net: inet: diag: Fix an error handling

2016-09-12 Thread David Ahern 
On 9/12/16 12:02 AM, Christophe JAILLET wrote:
> diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
> index abfbe492ebfe..795af25cf84c 100644
> --- a/net/ipv4/inet_diag.c
> +++ b/net/ipv4/inet_diag.c
> @@ -1134,7 +1134,6 @@ int inet_diag_handler_get_info(struct sk_buff *skb, 
> struct sock *sk)
>  
>   handler = inet_diag_lock_handler(sk->sk_protocol);
>   if (IS_ERR(handler)) {
> - inet_diag_unlock_handler(handler);
>   nlmsg_cancel(skb, nlh);
>   return PTR_ERR(handler);
>   }
> 

That call is needed. inet_diag_unlock_handler does not operate on the input arg 
but a global mutex. Perhaps a better patch is to change 
inet_diag_unlock_handler() to a void.

[PATCH] net: inet: diag: Fix an error handling

2016-09-12 Thread Christophe JAILLET 
If 'inet_diag_lock_handler()' returns an error, we should not call
'inet_diag_unlock_handler()' on it.
'handler' is not a valid mutexc in this case.

This has been spotted with the folowing coccinelle script:

@@
expression x;
identifier f;
@@

*   if (IS_ERR(x))
{
   ...
*  f(<+... x ...+>);
   ...
}

Signed-off-by: Christophe JAILLET 
---
 net/ipv4/inet_diag.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index abfbe492ebfe..795af25cf84c 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -1134,7 +1134,6 @@ int inet_diag_handler_get_info(struct sk_buff *skb, 
struct sock *sk)
 
handler = inet_diag_lock_handler(sk->sk_protocol);
if (IS_ERR(handler)) {
-   inet_diag_unlock_handler(handler);
nlmsg_cancel(skb, nlh);
return PTR_ERR(handler);
}
-- 
2.7.4