Re: [PATCH net-next] tcp: Add mark for TIMEWAIT sockets

[Jonathan Maxwell]

On Thu, May 10, 2018 at 1:32 PM, Eric Dumazet  wrote:
>
>
> On 05/09/2018 07:07 PM, Jon Maxwell wrote:
>> Aidan McGurn from Openwave Mobility systems reported the following bug:
>>
>> "Marked routing is broken on customer deployment. Its effects are large
>> increase in Uplink retransmissions caused by the client never receiving
>> the final ACK to their FINACK - this ACK misses the mark and routes out
>> of the incorrect route."
>>
>> Currently marks are added to sk_buffs for replies when the "fwmark_reflect"
>> sysctl is enabled. But not for TIME_WAIT sockets where the original socket 
>> had
>> sk->sk_mark set via setsockopt(SO_MARK..).
>>
>> Fix this in IPv4/v6 by adding tw->tw_mark for TIME_WAIT sockets. Copy the the
>> original sk->sk_mark in __inet_twsk_hashdance() to the new tw->tw_mark 
>> location.
>> Then copy this into ctl_sk->sk_mark so that the skb gets sent with the 
>> correct
>> mark. Do the same for resets. Give the "fwmark_reflect" sysctl precedence 
>> over
>> sk->sk_mark so that netfilter rules are still honored.
>>
>> Signed-off-by: Jon Maxwell 
>> ---
>>  include/net/inet_timewait_sock.h |  1 +
>>  net/ipv4/ip_output.c |  3 ++-
>>  net/ipv4/tcp_ipv4.c  | 18 --
>>  net/ipv4/tcp_minisocks.c |  1 +
>>  net/ipv6/tcp_ipv6.c  |  8 +++-
>>  5 files changed, 27 insertions(+), 4 deletions(-)
>>
>> diff --git a/include/net/inet_timewait_sock.h 
>> b/include/net/inet_timewait_sock.h
>> index c7be1ca8e562..659d8ed5a3bc 100644
>> --- a/include/net/inet_timewait_sock.h
>> +++ b/include/net/inet_timewait_sock.h
>> @@ -62,6 +62,7 @@ struct inet_timewait_sock {
>>  #define tw_dr__tw_common.skc_tw_dr
>>
>>   int tw_timeout;
>> + __u32   tw_mark;
>>   volatile unsigned char  tw_substate;
>>   unsigned char   tw_rcv_wscale;
>>
>> diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
>> index 95adb171f852..cca4412dc4cb 100644
>> --- a/net/ipv4/ip_output.c
>> +++ b/net/ipv4/ip_output.c
>> @@ -1539,6 +1539,7 @@ void ip_send_unicast_reply(struct sock *sk, struct 
>> sk_buff *skb,
>>   struct sk_buff *nskb;
>>   int err;
>>   int oif;
>> + __u32 mark = IP4_REPLY_MARK(net, skb->mark);
>>
>>   if (__ip_options_echo(net, , skb, sopt))
>>   return;
>> @@ -1561,7 +1562,7 @@ void ip_send_unicast_reply(struct sock *sk, struct 
>> sk_buff *skb,
>>   oif = skb->skb_iif;
>>
>>   flowi4_init_output(, oif,
>> -IP4_REPLY_MARK(net, skb->mark),
>> +mark ? (mark) : sk->sk_mark,
>
> You can avoid the declaration of mark variable and simply use here :
>
> IP4_REPLY_MARK(net, skb->mark) ?: sk->sk_mark,
>

Thanks for the advice and suggestions Eric. That is more elegant. Will do in v1.

>>  RT_TOS(arg->tos),
>>  RT_SCOPE_UNIVERSE, ip_hdr(skb)->protocol,
>>  ip_reply_arg_flowi_flags(arg),
>> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
>> index f70586b50838..fbee36579c83 100644
>> --- a/net/ipv4/tcp_ipv4.c
>> +++ b/net/ipv4/tcp_ipv4.c
>> @@ -621,6 +621,7 @@ static void tcp_v4_send_reset(const struct sock *sk, 
>> struct sk_buff *skb)
>>   struct sock *sk1 = NULL;
>>  #endif
>>   struct net *net;
>> + struct sock *ctl_sk;
>>
>>   /* Never send a reset in response to a reset. */
>>   if (th->rst)
>> @@ -723,11 +724,17 @@ static void tcp_v4_send_reset(const struct sock *sk, 
>> struct sk_buff *skb)
>>   arg.tos = ip_hdr(skb)->tos;
>>   arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
>>   local_bh_disable();
>> - ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
>> + ctl_sk = *this_cpu_ptr(net->ipv4.tcp_sk);
>> + if (sk && sk->sk_state == TCP_TIME_WAIT)
>> + ctl_sk->sk_mark = inet_twsk(sk)->tw_mark;
>> + else if (sk && sk_fullsock(sk))
>> + ctl_sk->sk_mark = sk->sk_mark;
>> + ip_send_unicast_reply(ctl_sk,
>> skb, _SKB_CB(skb)->header.h4.opt,
>> ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
>> , arg.iov[0].iov_len);
>>
>> + ctl_sk->sk_mark = 0;
>>   __TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
>>   __TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
>>   local_bh_enable();
>> @@ -759,6 +766,7 @@ static void tcp_v4_send_ack(const struct sock *sk,
>>   } rep;
>>   struct net *net = sock_net(sk);
>>   struct ip_reply_arg arg;
>> + struct sock *ctl_sk;
>>
>>   memset(, 0, sizeof(struct tcphdr));
>>   memset(, 0, sizeof(arg));
>> @@ -809,11 +817,17 @@ static void tcp_v4_send_ack(const struct sock *sk,
>>   arg.tos = tos;
>>   arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL);
>>   local_bh_disable();
>> - 

Re: [PATCH net-next] tcp: Add mark for TIMEWAIT sockets

[Jonathan Maxwell]

On Thu, May 10, 2018 at 1:32 PM, Eric Dumazet  wrote:
>
>
> On 05/09/2018 07:07 PM, Jon Maxwell wrote:
>> Aidan McGurn from Openwave Mobility systems reported the following bug:
>>
>> "Marked routing is broken on customer deployment. Its effects are large
>> increase in Uplink retransmissions caused by the client never receiving
>> the final ACK to their FINACK - this ACK misses the mark and routes out
>> of the incorrect route."
>>
>> Currently marks are added to sk_buffs for replies when the "fwmark_reflect"
>> sysctl is enabled. But not for TIME_WAIT sockets where the original socket 
>> had
>> sk->sk_mark set via setsockopt(SO_MARK..).
>>
>> Fix this in IPv4/v6 by adding tw->tw_mark for TIME_WAIT sockets. Copy the the
>> original sk->sk_mark in __inet_twsk_hashdance() to the new tw->tw_mark 
>> location.
>> Then copy this into ctl_sk->sk_mark so that the skb gets sent with the 
>> correct
>> mark. Do the same for resets. Give the "fwmark_reflect" sysctl precedence 
>> over
>> sk->sk_mark so that netfilter rules are still honored.
>>
>> Signed-off-by: Jon Maxwell 
>> ---
>>  include/net/inet_timewait_sock.h |  1 +
>>  net/ipv4/ip_output.c |  3 ++-
>>  net/ipv4/tcp_ipv4.c  | 18 --
>>  net/ipv4/tcp_minisocks.c |  1 +
>>  net/ipv6/tcp_ipv6.c  |  8 +++-
>>  5 files changed, 27 insertions(+), 4 deletions(-)
>>
>> diff --git a/include/net/inet_timewait_sock.h 
>> b/include/net/inet_timewait_sock.h
>> index c7be1ca8e562..659d8ed5a3bc 100644
>> --- a/include/net/inet_timewait_sock.h
>> +++ b/include/net/inet_timewait_sock.h
>> @@ -62,6 +62,7 @@ struct inet_timewait_sock {
>>  #define tw_dr__tw_common.skc_tw_dr
>>
>>   int tw_timeout;
>> + __u32   tw_mark;
>>   volatile unsigned char  tw_substate;
>>   unsigned char   tw_rcv_wscale;
>>
>> diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
>> index 95adb171f852..cca4412dc4cb 100644
>> --- a/net/ipv4/ip_output.c
>> +++ b/net/ipv4/ip_output.c
>> @@ -1539,6 +1539,7 @@ void ip_send_unicast_reply(struct sock *sk, struct 
>> sk_buff *skb,
>>   struct sk_buff *nskb;
>>   int err;
>>   int oif;
>> + __u32 mark = IP4_REPLY_MARK(net, skb->mark);
>>
>>   if (__ip_options_echo(net, , skb, sopt))
>>   return;
>> @@ -1561,7 +1562,7 @@ void ip_send_unicast_reply(struct sock *sk, struct 
>> sk_buff *skb,
>>   oif = skb->skb_iif;
>>
>>   flowi4_init_output(, oif,
>> -IP4_REPLY_MARK(net, skb->mark),
>> +mark ? (mark) : sk->sk_mark,
>
> You can avoid the declaration of mark variable and simply use here :
>
> IP4_REPLY_MARK(net, skb->mark) ?: sk->sk_mark,
>

Thanks for the advice and suggestions Eric. That is more elegant. Will do in v1.

>>  RT_TOS(arg->tos),
>>  RT_SCOPE_UNIVERSE, ip_hdr(skb)->protocol,
>>  ip_reply_arg_flowi_flags(arg),
>> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
>> index f70586b50838..fbee36579c83 100644
>> --- a/net/ipv4/tcp_ipv4.c
>> +++ b/net/ipv4/tcp_ipv4.c
>> @@ -621,6 +621,7 @@ static void tcp_v4_send_reset(const struct sock *sk, 
>> struct sk_buff *skb)
>>   struct sock *sk1 = NULL;
>>  #endif
>>   struct net *net;
>> + struct sock *ctl_sk;
>>
>>   /* Never send a reset in response to a reset. */
>>   if (th->rst)
>> @@ -723,11 +724,17 @@ static void tcp_v4_send_reset(const struct sock *sk, 
>> struct sk_buff *skb)
>>   arg.tos = ip_hdr(skb)->tos;
>>   arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
>>   local_bh_disable();
>> - ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
>> + ctl_sk = *this_cpu_ptr(net->ipv4.tcp_sk);
>> + if (sk && sk->sk_state == TCP_TIME_WAIT)
>> + ctl_sk->sk_mark = inet_twsk(sk)->tw_mark;
>> + else if (sk && sk_fullsock(sk))
>> + ctl_sk->sk_mark = sk->sk_mark;
>> + ip_send_unicast_reply(ctl_sk,
>> skb, _SKB_CB(skb)->header.h4.opt,
>> ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
>> , arg.iov[0].iov_len);
>>
>> + ctl_sk->sk_mark = 0;
>>   __TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
>>   __TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
>>   local_bh_enable();
>> @@ -759,6 +766,7 @@ static void tcp_v4_send_ack(const struct sock *sk,
>>   } rep;
>>   struct net *net = sock_net(sk);
>>   struct ip_reply_arg arg;
>> + struct sock *ctl_sk;
>>
>>   memset(, 0, sizeof(struct tcphdr));
>>   memset(, 0, sizeof(arg));
>> @@ -809,11 +817,17 @@ static void tcp_v4_send_ack(const struct sock *sk,
>>   arg.tos = tos;
>>   arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL);
>>   local_bh_disable();
>> - ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
>> + ctl_sk = 

Re: [PATCH net-next] tcp: Add mark for TIMEWAIT sockets

[Eric Dumazet]

On 05/09/2018 07:07 PM, Jon Maxwell wrote:
> Aidan McGurn from Openwave Mobility systems reported the following bug:
> 
> "Marked routing is broken on customer deployment. Its effects are large 
> increase in Uplink retransmissions caused by the client never receiving 
> the final ACK to their FINACK - this ACK misses the mark and routes out 
> of the incorrect route."
> 
> Currently marks are added to sk_buffs for replies when the "fwmark_reflect" 
> sysctl is enabled. But not for TIME_WAIT sockets where the original socket 
> had 
> sk->sk_mark set via setsockopt(SO_MARK..).  
> 
> Fix this in IPv4/v6 by adding tw->tw_mark for TIME_WAIT sockets. Copy the the 
> original sk->sk_mark in __inet_twsk_hashdance() to the new tw->tw_mark 
> location. 
> Then copy this into ctl_sk->sk_mark so that the skb gets sent with the 
> correct 
> mark. Do the same for resets. Give the "fwmark_reflect" sysctl precedence 
> over 
> sk->sk_mark so that netfilter rules are still honored.
> 
> Signed-off-by: Jon Maxwell 
> ---
>  include/net/inet_timewait_sock.h |  1 +
>  net/ipv4/ip_output.c |  3 ++-
>  net/ipv4/tcp_ipv4.c  | 18 --
>  net/ipv4/tcp_minisocks.c |  1 +
>  net/ipv6/tcp_ipv6.c  |  8 +++-
>  5 files changed, 27 insertions(+), 4 deletions(-)
> 
> diff --git a/include/net/inet_timewait_sock.h 
> b/include/net/inet_timewait_sock.h
> index c7be1ca8e562..659d8ed5a3bc 100644
> --- a/include/net/inet_timewait_sock.h
> +++ b/include/net/inet_timewait_sock.h
> @@ -62,6 +62,7 @@ struct inet_timewait_sock {
>  #define tw_dr__tw_common.skc_tw_dr
>  
>   int tw_timeout;
> + __u32   tw_mark;
>   volatile unsigned char  tw_substate;
>   unsigned char   tw_rcv_wscale;
>  
> diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
> index 95adb171f852..cca4412dc4cb 100644
> --- a/net/ipv4/ip_output.c
> +++ b/net/ipv4/ip_output.c
> @@ -1539,6 +1539,7 @@ void ip_send_unicast_reply(struct sock *sk, struct 
> sk_buff *skb,
>   struct sk_buff *nskb;
>   int err;
>   int oif;
> + __u32 mark = IP4_REPLY_MARK(net, skb->mark);
>  
>   if (__ip_options_echo(net, , skb, sopt))
>   return;
> @@ -1561,7 +1562,7 @@ void ip_send_unicast_reply(struct sock *sk, struct 
> sk_buff *skb,
>   oif = skb->skb_iif;
>  
>   flowi4_init_output(, oif,
> -IP4_REPLY_MARK(net, skb->mark),
> +mark ? (mark) : sk->sk_mark,

You can avoid the declaration of mark variable and simply use here :

IP4_REPLY_MARK(net, skb->mark) ?: sk->sk_mark,

>  RT_TOS(arg->tos),
>  RT_SCOPE_UNIVERSE, ip_hdr(skb)->protocol,
>  ip_reply_arg_flowi_flags(arg),
> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
> index f70586b50838..fbee36579c83 100644
> --- a/net/ipv4/tcp_ipv4.c
> +++ b/net/ipv4/tcp_ipv4.c
> @@ -621,6 +621,7 @@ static void tcp_v4_send_reset(const struct sock *sk, 
> struct sk_buff *skb)
>   struct sock *sk1 = NULL;
>  #endif
>   struct net *net;
> + struct sock *ctl_sk;
>  
>   /* Never send a reset in response to a reset. */
>   if (th->rst)
> @@ -723,11 +724,17 @@ static void tcp_v4_send_reset(const struct sock *sk, 
> struct sk_buff *skb)
>   arg.tos = ip_hdr(skb)->tos;
>   arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
>   local_bh_disable();
> - ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
> + ctl_sk = *this_cpu_ptr(net->ipv4.tcp_sk);
> + if (sk && sk->sk_state == TCP_TIME_WAIT)
> + ctl_sk->sk_mark = inet_twsk(sk)->tw_mark;
> + else if (sk && sk_fullsock(sk))
> + ctl_sk->sk_mark = sk->sk_mark;
> + ip_send_unicast_reply(ctl_sk,
> skb, _SKB_CB(skb)->header.h4.opt,
> ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
> , arg.iov[0].iov_len);
>  
> + ctl_sk->sk_mark = 0;
>   __TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
>   __TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
>   local_bh_enable();
> @@ -759,6 +766,7 @@ static void tcp_v4_send_ack(const struct sock *sk,
>   } rep;
>   struct net *net = sock_net(sk);
>   struct ip_reply_arg arg;
> + struct sock *ctl_sk;
>  
>   memset(, 0, sizeof(struct tcphdr));
>   memset(, 0, sizeof(arg));
> @@ -809,11 +817,17 @@ static void tcp_v4_send_ack(const struct sock *sk,
>   arg.tos = tos;
>   arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL);
>   local_bh_disable();
> - ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
> + ctl_sk = *this_cpu_ptr(net->ipv4.tcp_sk);
> + if (sk && sk->sk_state == TCP_TIME_WAIT)
> + ctl_sk->sk_mark = inet_twsk(sk)->tw_mark;
> + else if (sk && sk_fullsock(sk))
> + 

Re: [PATCH net-next] tcp: Add mark for TIMEWAIT sockets

[Eric Dumazet]

On 05/09/2018 07:07 PM, Jon Maxwell wrote:
> Aidan McGurn from Openwave Mobility systems reported the following bug:
> 
> "Marked routing is broken on customer deployment. Its effects are large 
> increase in Uplink retransmissions caused by the client never receiving 
> the final ACK to their FINACK - this ACK misses the mark and routes out 
> of the incorrect route."
> 
> Currently marks are added to sk_buffs for replies when the "fwmark_reflect" 
> sysctl is enabled. But not for TIME_WAIT sockets where the original socket 
> had 
> sk->sk_mark set via setsockopt(SO_MARK..).  
> 
> Fix this in IPv4/v6 by adding tw->tw_mark for TIME_WAIT sockets. Copy the the 
> original sk->sk_mark in __inet_twsk_hashdance() to the new tw->tw_mark 
> location. 
> Then copy this into ctl_sk->sk_mark so that the skb gets sent with the 
> correct 
> mark. Do the same for resets. Give the "fwmark_reflect" sysctl precedence 
> over 
> sk->sk_mark so that netfilter rules are still honored.
> 
> Signed-off-by: Jon Maxwell 
> ---
>  include/net/inet_timewait_sock.h |  1 +
>  net/ipv4/ip_output.c |  3 ++-
>  net/ipv4/tcp_ipv4.c  | 18 --
>  net/ipv4/tcp_minisocks.c |  1 +
>  net/ipv6/tcp_ipv6.c  |  8 +++-
>  5 files changed, 27 insertions(+), 4 deletions(-)
> 
> diff --git a/include/net/inet_timewait_sock.h 
> b/include/net/inet_timewait_sock.h
> index c7be1ca8e562..659d8ed5a3bc 100644
> --- a/include/net/inet_timewait_sock.h
> +++ b/include/net/inet_timewait_sock.h
> @@ -62,6 +62,7 @@ struct inet_timewait_sock {
>  #define tw_dr__tw_common.skc_tw_dr
>  
>   int tw_timeout;
> + __u32   tw_mark;
>   volatile unsigned char  tw_substate;
>   unsigned char   tw_rcv_wscale;
>  
> diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
> index 95adb171f852..cca4412dc4cb 100644
> --- a/net/ipv4/ip_output.c
> +++ b/net/ipv4/ip_output.c
> @@ -1539,6 +1539,7 @@ void ip_send_unicast_reply(struct sock *sk, struct 
> sk_buff *skb,
>   struct sk_buff *nskb;
>   int err;
>   int oif;
> + __u32 mark = IP4_REPLY_MARK(net, skb->mark);
>  
>   if (__ip_options_echo(net, , skb, sopt))
>   return;
> @@ -1561,7 +1562,7 @@ void ip_send_unicast_reply(struct sock *sk, struct 
> sk_buff *skb,
>   oif = skb->skb_iif;
>  
>   flowi4_init_output(, oif,
> -IP4_REPLY_MARK(net, skb->mark),
> +mark ? (mark) : sk->sk_mark,

You can avoid the declaration of mark variable and simply use here :

IP4_REPLY_MARK(net, skb->mark) ?: sk->sk_mark,

>  RT_TOS(arg->tos),
>  RT_SCOPE_UNIVERSE, ip_hdr(skb)->protocol,
>  ip_reply_arg_flowi_flags(arg),
> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
> index f70586b50838..fbee36579c83 100644
> --- a/net/ipv4/tcp_ipv4.c
> +++ b/net/ipv4/tcp_ipv4.c
> @@ -621,6 +621,7 @@ static void tcp_v4_send_reset(const struct sock *sk, 
> struct sk_buff *skb)
>   struct sock *sk1 = NULL;
>  #endif
>   struct net *net;
> + struct sock *ctl_sk;
>  
>   /* Never send a reset in response to a reset. */
>   if (th->rst)
> @@ -723,11 +724,17 @@ static void tcp_v4_send_reset(const struct sock *sk, 
> struct sk_buff *skb)
>   arg.tos = ip_hdr(skb)->tos;
>   arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
>   local_bh_disable();
> - ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
> + ctl_sk = *this_cpu_ptr(net->ipv4.tcp_sk);
> + if (sk && sk->sk_state == TCP_TIME_WAIT)
> + ctl_sk->sk_mark = inet_twsk(sk)->tw_mark;
> + else if (sk && sk_fullsock(sk))
> + ctl_sk->sk_mark = sk->sk_mark;
> + ip_send_unicast_reply(ctl_sk,
> skb, _SKB_CB(skb)->header.h4.opt,
> ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
> , arg.iov[0].iov_len);
>  
> + ctl_sk->sk_mark = 0;
>   __TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
>   __TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
>   local_bh_enable();
> @@ -759,6 +766,7 @@ static void tcp_v4_send_ack(const struct sock *sk,
>   } rep;
>   struct net *net = sock_net(sk);
>   struct ip_reply_arg arg;
> + struct sock *ctl_sk;
>  
>   memset(, 0, sizeof(struct tcphdr));
>   memset(, 0, sizeof(arg));
> @@ -809,11 +817,17 @@ static void tcp_v4_send_ack(const struct sock *sk,
>   arg.tos = tos;
>   arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL);
>   local_bh_disable();
> - ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
> + ctl_sk = *this_cpu_ptr(net->ipv4.tcp_sk);
> + if (sk && sk->sk_state == TCP_TIME_WAIT)
> + ctl_sk->sk_mark = inet_twsk(sk)->tw_mark;
> + else if (sk && sk_fullsock(sk))
> + ctl_sk->sk_mark = sk->sk_mark;
> +