diff mbox series

[PATCHv3,net-next,1/2] udp: call udp_encap_enable for v6 sockets when enabling encap

Message ID 0ba74e791c186444af53489ebc55664462a1caf6.1610771509.git.lucien.xin@gmail.com
State New
Headers show
Series net: enable udp v6 sockets receiving v4 packets with UDP GRO | expand

Commit Message

Xin Long Jan. 16, 2021, 4:32 a.m. UTC
When enabling encap for a ipv6 socket without udp_encap_needed_key
increased, UDP GRO won't work for v4 mapped v6 address packets as
sk will be NULL in udp4_gro_receive().

This patch is to enable it by increasing udp_encap_needed_key for
v6 sockets in udp_tunnel_encap_enable(), and correspondingly
decrease udp_encap_needed_key in udpv6_destroy_sock().

v1->v2:
  - add udp_encap_disable() and export it.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 include/net/udp.h        | 1 +
 include/net/udp_tunnel.h | 3 +--
 net/ipv4/udp.c           | 6 ++++++
 net/ipv6/udp.c           | 4 +++-
 4 files changed, 11 insertions(+), 3 deletions(-)

Comments

Alexander Duyck Jan. 19, 2021, 10:17 p.m. UTC | #1
On Fri, Jan 15, 2021 at 8:34 PM Xin Long <lucien.xin@gmail.com> wrote:
>

> When enabling encap for a ipv6 socket without udp_encap_needed_key

> increased, UDP GRO won't work for v4 mapped v6 address packets as

> sk will be NULL in udp4_gro_receive().

>

> This patch is to enable it by increasing udp_encap_needed_key for

> v6 sockets in udp_tunnel_encap_enable(), and correspondingly

> decrease udp_encap_needed_key in udpv6_destroy_sock().

>

> v1->v2:

>   - add udp_encap_disable() and export it.

>

> Signed-off-by: Xin Long <lucien.xin@gmail.com>

> ---

>  include/net/udp.h        | 1 +

>  include/net/udp_tunnel.h | 3 +--

>  net/ipv4/udp.c           | 6 ++++++

>  net/ipv6/udp.c           | 4 +++-

>  4 files changed, 11 insertions(+), 3 deletions(-)

>

> diff --git a/include/net/udp.h b/include/net/udp.h

> index 877832b..1e7b6cd 100644

> --- a/include/net/udp.h

> +++ b/include/net/udp.h

> @@ -467,6 +467,7 @@ void udp_init(void);

>

>  DECLARE_STATIC_KEY_FALSE(udp_encap_needed_key);

>  void udp_encap_enable(void);

> +void udp_encap_disable(void);

>  #if IS_ENABLED(CONFIG_IPV6)

>  DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key);

>  void udpv6_encap_enable(void);

> diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h

> index 282d10e..afc7ce7 100644

> --- a/include/net/udp_tunnel.h

> +++ b/include/net/udp_tunnel.h

> @@ -181,9 +181,8 @@ static inline void udp_tunnel_encap_enable(struct socket *sock)

>  #if IS_ENABLED(CONFIG_IPV6)

>         if (sock->sk->sk_family == PF_INET6)

>                 ipv6_stub->udpv6_encap_enable();

> -       else

>  #endif

> -               udp_encap_enable();

> +       udp_encap_enable();

>  }

>

>  #define UDP_TUNNEL_NIC_MAX_TABLES      4

> diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c

> index 7103b0a..28bfe60 100644

> --- a/net/ipv4/udp.c

> +++ b/net/ipv4/udp.c

> @@ -596,6 +596,12 @@ void udp_encap_enable(void)

>  }

>  EXPORT_SYMBOL(udp_encap_enable);

>

> +void udp_encap_disable(void)

> +{

> +       static_branch_dec(&udp_encap_needed_key);

> +}

> +EXPORT_SYMBOL(udp_encap_disable);

> +

>  /* Handler for tunnels with arbitrary destination ports: no socket lookup, go

>   * through error handlers in encapsulations looking for a match.

>   */


So this seems unbalanced to me. We are adding/modifying one spot where
we are calling the enable function, but the other callers don't call
the disable function? Specifically I am curious about how to deal with
the rxrpc_open_socket usage.

If we don't balance out all the callers I am not sure adding the
udp_encap_disable makes much sense.

> diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c

> index b9f3dfd..d754292 100644

> --- a/net/ipv6/udp.c

> +++ b/net/ipv6/udp.c

> @@ -1608,8 +1608,10 @@ void udpv6_destroy_sock(struct sock *sk)

>                         if (encap_destroy)

>                                 encap_destroy(sk);

>                 }

> -               if (up->encap_enabled)

> +               if (up->encap_enabled) {

>                         static_branch_dec(&udpv6_encap_needed_key);

> +                       udp_encap_disable();

> +               }

>         }

>

>         inet6_destroy_sock(sk);

> --

> 2.1.0

>
Xin Long Jan. 20, 2021, 2:55 a.m. UTC | #2
On Wed, Jan 20, 2021 at 6:17 AM Alexander Duyck
<alexander.duyck@gmail.com> wrote:
>

> On Fri, Jan 15, 2021 at 8:34 PM Xin Long <lucien.xin@gmail.com> wrote:

> >

> > When enabling encap for a ipv6 socket without udp_encap_needed_key

> > increased, UDP GRO won't work for v4 mapped v6 address packets as

> > sk will be NULL in udp4_gro_receive().

> >

> > This patch is to enable it by increasing udp_encap_needed_key for

> > v6 sockets in udp_tunnel_encap_enable(), and correspondingly

> > decrease udp_encap_needed_key in udpv6_destroy_sock().

> >

> > v1->v2:

> >   - add udp_encap_disable() and export it.

> >

> > Signed-off-by: Xin Long <lucien.xin@gmail.com>

> > ---

> >  include/net/udp.h        | 1 +

> >  include/net/udp_tunnel.h | 3 +--

> >  net/ipv4/udp.c           | 6 ++++++

> >  net/ipv6/udp.c           | 4 +++-

> >  4 files changed, 11 insertions(+), 3 deletions(-)

> >

> > diff --git a/include/net/udp.h b/include/net/udp.h

> > index 877832b..1e7b6cd 100644

> > --- a/include/net/udp.h

> > +++ b/include/net/udp.h

> > @@ -467,6 +467,7 @@ void udp_init(void);

> >

> >  DECLARE_STATIC_KEY_FALSE(udp_encap_needed_key);

> >  void udp_encap_enable(void);

> > +void udp_encap_disable(void);

> >  #if IS_ENABLED(CONFIG_IPV6)

> >  DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key);

> >  void udpv6_encap_enable(void);

> > diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h

> > index 282d10e..afc7ce7 100644

> > --- a/include/net/udp_tunnel.h

> > +++ b/include/net/udp_tunnel.h

> > @@ -181,9 +181,8 @@ static inline void udp_tunnel_encap_enable(struct socket *sock)

> >  #if IS_ENABLED(CONFIG_IPV6)

> >         if (sock->sk->sk_family == PF_INET6)

> >                 ipv6_stub->udpv6_encap_enable();

> > -       else

> >  #endif

> > -               udp_encap_enable();

> > +       udp_encap_enable();

> >  }

> >

> >  #define UDP_TUNNEL_NIC_MAX_TABLES      4

> > diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c

> > index 7103b0a..28bfe60 100644

> > --- a/net/ipv4/udp.c

> > +++ b/net/ipv4/udp.c

> > @@ -596,6 +596,12 @@ void udp_encap_enable(void)

> >  }

> >  EXPORT_SYMBOL(udp_encap_enable);

> >

> > +void udp_encap_disable(void)

> > +{

> > +       static_branch_dec(&udp_encap_needed_key);

> > +}

> > +EXPORT_SYMBOL(udp_encap_disable);

> > +

> >  /* Handler for tunnels with arbitrary destination ports: no socket lookup, go

> >   * through error handlers in encapsulations looking for a match.

> >   */

>

> So this seems unbalanced to me. We are adding/modifying one spot where

> we are calling the enable function, but the other callers don't call

> the disable function? Specifically I am curious about how to deal with

> the rxrpc_open_socket usage.

as long as it's a UDP sock, when it's being destroyed,
udp(v6)_destroy_sock will be called, where the key(s) get decreased.

Sorry, I missed there's a call to udp_encap_enable() in rxrpc, the issue is
the similar to the one in bareudp, it should be:

-       udp_encap_enable();
 #if IS_ENABLED(CONFIG_AF_RXRPC_IPV6)
        if (local->srx.transport.family == AF_INET6)
                udpv6_encap_enable();
+       else
 #endif
+       udp_encap_enable();
+

I will get all these into one patch and repost.

Interesting it doesn't use udp_tunnel APIs here, I will check.

Thanks.

>

> If we don't balance out all the callers I am not sure adding the

> udp_encap_disable makes much sense.

>

> > diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c

> > index b9f3dfd..d754292 100644

> > --- a/net/ipv6/udp.c

> > +++ b/net/ipv6/udp.c

> > @@ -1608,8 +1608,10 @@ void udpv6_destroy_sock(struct sock *sk)

> >                         if (encap_destroy)

> >                                 encap_destroy(sk);

> >                 }

> > -               if (up->encap_enabled)

> > +               if (up->encap_enabled) {

> >                         static_branch_dec(&udpv6_encap_needed_key);

> > +                       udp_encap_disable();

> > +               }

> >         }

> >

> >         inet6_destroy_sock(sk);

> > --

> > 2.1.0

> >
diff mbox series

Patch

diff --git a/include/net/udp.h b/include/net/udp.h
index 877832b..1e7b6cd 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -467,6 +467,7 @@  void udp_init(void);
 
 DECLARE_STATIC_KEY_FALSE(udp_encap_needed_key);
 void udp_encap_enable(void);
+void udp_encap_disable(void);
 #if IS_ENABLED(CONFIG_IPV6)
 DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
 void udpv6_encap_enable(void);
diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index 282d10e..afc7ce7 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -181,9 +181,8 @@  static inline void udp_tunnel_encap_enable(struct socket *sock)
 #if IS_ENABLED(CONFIG_IPV6)
 	if (sock->sk->sk_family == PF_INET6)
 		ipv6_stub->udpv6_encap_enable();
-	else
 #endif
-		udp_encap_enable();
+	udp_encap_enable();
 }
 
 #define UDP_TUNNEL_NIC_MAX_TABLES	4
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 7103b0a..28bfe60 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -596,6 +596,12 @@  void udp_encap_enable(void)
 }
 EXPORT_SYMBOL(udp_encap_enable);
 
+void udp_encap_disable(void)
+{
+	static_branch_dec(&udp_encap_needed_key);
+}
+EXPORT_SYMBOL(udp_encap_disable);
+
 /* Handler for tunnels with arbitrary destination ports: no socket lookup, go
  * through error handlers in encapsulations looking for a match.
  */
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index b9f3dfd..d754292 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1608,8 +1608,10 @@  void udpv6_destroy_sock(struct sock *sk)
 			if (encap_destroy)
 				encap_destroy(sk);
 		}
-		if (up->encap_enabled)
+		if (up->encap_enabled) {
 			static_branch_dec(&udpv6_encap_needed_key);
+			udp_encap_disable();
+		}
 	}
 
 	inet6_destroy_sock(sk);