Re: [PATCH v6 3/4] mptcp: build ADD_ADDR/echo-ADD_ADDR option according pm.add_signal

[Yonglong Li <liyonglong@chinatelecom.cn>]

On 2021/6/30 10:05, Geliang Tang wrote:
> Yonglong Li <liyonglong@chinatelecom.cn> 于2021年6月30日周三 上午9:30写道：
>>
>>
>>
>> On 2021/6/29 16:25, Geliang Tang wrote:
>>> Yonglong Li <liyonglong@chinatelecom.cn> 于2021年6月29日周二 下午3:54写道：
>>>>
>>>>
>>>>
>>>> On 2021/6/29 15:35, Geliang Tang wrote:
>>>>> Yonglong Li <liyonglong@chinatelecom.cn> 于2021年6月29日周二 下午3:02写道：
>>>>>>
>>>>>>
>>>>>> Hi Geiliang, Thanks for your reviews.
>>>>>>
>>>>>> On 2021/6/29 13:58, Geliang Tang wrote:
>>>>>>> Yonglong Li <liyonglong@chinatelecom.cn> 于2021年6月29日周二 上午9:42写道：
>>>>>>>>
>>>>>>>> according MPTCP_ADD_ADDR_SIGNAL and MPTCP_ADD_ADDR_ECHO flag build
>>>>>>>> ADD_ADDR/echo-ADD_ADDR option
>>>>>>>>
>>>>>>>> add a suboptions type OPTION_MPTCP_ADD_ECHO to mark as echo option
>>>>>>>>
>>>>>>>> Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
>>>>>>>> ---
>>>>>>>>  include/net/mptcp.h  |  3 ++-
>>>>>>>>  net/mptcp/options.c  | 65 +++++++++++++++++++++++++++++++---------------------
>>>>>>>>  net/mptcp/pm.c       | 33 +++++++++++---------------
>>>>>>>>  net/mptcp/protocol.h | 23 ++++++++++++-------
>>>>>>>>  4 files changed, 69 insertions(+), 55 deletions(-)
>>>>>>>>
>>>>>>>> diff --git a/include/net/mptcp.h b/include/net/mptcp.h
>>>>>>>> index d61bbbf..d2c6ebe 100644
>>>>>>>> --- a/include/net/mptcp.h
>>>>>>>> +++ b/include/net/mptcp.h
>>>>>>>> @@ -61,7 +61,8 @@ struct mptcp_out_options {
>>>>>>>>         u64 sndr_key;
>>>>>>>>         u64 rcvr_key;
>>>>>>>>         u64 ahmac;
>>>>>>>> -       struct mptcp_addr_info addr;
>>>>>>>> +       struct mptcp_addr_info local;
>>>>>>>> +       struct mptcp_addr_info remote;
>>>>>>>>         struct mptcp_rm_list rm_list;
>>>>>>>>         u8 join_id;
>>>>>>>>         u8 backup;
>>>>>>>> diff --git a/net/mptcp/options.c b/net/mptcp/options.c
>>>>>>>> index 1aec016..1707bec 100644
>>>>>>>> --- a/net/mptcp/options.c
>>>>>>>> +++ b/net/mptcp/options.c
>>>>>>>> @@ -655,13 +655,15 @@ static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *
>>>>>>>>         struct mptcp_sock *msk = mptcp_sk(subflow->conn);
>>>>>>>>         bool drop_other_suboptions = false;
>>>>>>>>         unsigned int opt_size = *size;
>>>>>>>> -       bool echo;
>>>>>>>> -       bool port;
>>>>>>>> -       int len;
>>>>>>>> +       u8 add_addr, flags = 0xff;
>>>>>>>> +       int len = 0;
>>>>>>>>
>>>>>>>> -       if ((mptcp_pm_should_add_signal_ipv6(msk) ||
>>>>>>>> -            mptcp_pm_should_add_signal_port(msk) ||
>>>>>>>> -            mptcp_pm_should_add_signal_echo(msk)) &&
>>>>>>>> +       if (!mptcp_pm_add_addr_signal(msk, opts, &add_addr))
>>>>>>>> +               return false;
>>>>>>>
>>>>>>> This add_addr argument is useless, let's drop it.
>>>>>>>
>>>>>> we can use add_addr use in debug log.
>>>>>
>>>>> I think it's not worth adding a new argument just for debugging.
>>>> agree.
>>>>
>>>>>
>>>>>>
>>>>>>> And here add back mptcp_pm_should_add_signal check here. The original code
>>>>>>> called mptcp_pm_should_add_signal twice for double check, once out of pm
>>>>>>> lock, once under pm lock. We should keep it.
>>>>>> Sorry, I think double check is not necessary. does we need double check?
>>>>>
>>>>> I think we should keep the original logic here. If we want to drop this
>>>>> double check or something, we should do it in another patch, don't mix too
>>>>> much things in one patch.
>>>> agree.
>>>>
>>>>>
>>>>>>
>>>>>>>
>>>>>>>> +
>>>>>>>> +       if ((mptcp_pm_should_add_signal_echo(msk) ||
>>>>>>>> +            (mptcp_pm_should_add_signal_addr(msk) &&
>>>>>>>> +             (opts->local.family == AF_INET6 || opts->local.port))) &&
>>>>>>>>             skb && skb_is_tcp_pure_ack(skb)) {
>>>>>>>>                 pr_debug("drop other suboptions");
>>>>>>>>                 opts->suboptions = 0;
>>>>>>>> @@ -671,11 +673,17 @@ static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *
>>>>>>>>                 drop_other_suboptions = true;
>>>>>>>>         }
>>>>>>>>
>>>>>>>> -       if (!mptcp_pm_should_add_signal(msk) ||
>>>>>>>> -           !(mptcp_pm_add_addr_signal(msk, remaining, &opts->addr, &echo, &port)))
>>>>>>>> -               return false;
>>>>>>>>
>>>>>>>> -       len = mptcp_add_addr_len(opts->addr.family, echo, port);
>>>>>>>> +       if (mptcp_pm_should_add_signal_echo(msk)) {
>>>>>>>> +               flags = (u8)~BIT(MPTCP_ADD_ADDR_ECHO);
>>>>>>>> +       } else {
>>>>>>>> +               opts->ahmac = add_addr_generate_hmac(msk->local_key,
>>>>>>>> +                                                    msk->remote_key,
>>>>>>>> +                                                    &opts->local);
>>>>>>>
>>>>>>> Keep this ahmac generating code after opts->suboptions set just like the
>>>>>>> original code, since ahmac is the more expensive to populate. If remaining
>>>>>>> length isn't enough, no need to set ahmac.
>>>>>>
>>>>>> because mptcp_add_addr_len(opts) will use ahmac to calculate len of opts, so I think Keep this ahmac
>>>>>> generating code after opts->suboptions set is not ok.
>>>>>
>>>>> So we should use mptcp_pm_should_add_signal_addr instead of opts->ahmac in
>>>>> mptcp_add_addr_len.
>>>> agree.
>>>>
>>>>>
>>>>>>
>>>>>>>
>>>>>>>> +               flags = (u8)~BIT(MPTCP_ADD_ADDR_SIGNAL);
>>>>>>>> +       }
>>>>>>>> +
>>>>>>>> +       len = mptcp_add_addr_len(opts);
>>>>>>>>         if (remaining < len)
>>>>>>>>                 return false;
>>>>>>>>
>>>>>>>> @@ -683,13 +691,14 @@ static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *
>>>>>>>>         if (drop_other_suboptions)
>>>>>>>>                 *size -= opt_size;
>>>>>>>>         opts->suboptions |= OPTION_MPTCP_ADD_ADDR;
>>>>>>>> -       if (!echo) {
>>>>>>>> -               opts->ahmac = add_addr_generate_hmac(msk->local_key,
>>>>>>>> -                                                    msk->remote_key,
>>>>>>>> -                                                    &opts->addr);
>>>>>>>> -       }
>>>>>>>> -       pr_debug("addr_id=%d, ahmac=%llu, echo=%d, port=%d",
>>>>>>>> -                opts->addr.id, opts->ahmac, echo, ntohs(opts->addr.port));
>>>>>>>> +
>>>>>>>> +       spin_lock_bh(&msk->pm.lock);
>>>>>>>> +       WRITE_ONCE(msk->pm.addr_signal, flags & msk->pm.addr_signal);
>>>>>>>> +       spin_unlock_bh(&msk->pm.lock);
>>>>>>>
>>>>>>> addr_signal has been set in mptcp_pm_add_addr_signal in patch 1, no need to
>>>>>>> set it again. I thinks this trunk and all the flags set above should be
>>>>>>> dropped.
>>>>>>
>>>>>> Because MPTCP_ADD_ADDR_SIGNAL and MPTCP_ADD_ADDR_ECHO maybe set at the same time.
>>>>>> So i think we should only unset one flag.
>>>>>
>>>>> We can only unset one flag in mptcp_pm_add_addr_signal, see my comment in
>>>>> patch 1.
>>>>
>>>> if change like this. there is a issue: if remaining len checking is not ok and return false, The ADD_ADDR/ECHO event will
>>>> be clear. So I think we should make sure ADD_ADDR/ECHO option will add in packet before clean flags. WDYT?
>>>>
>>>
>>> You're right, let's clear it in mptcp_established_options_add_addr.
>>> Furthermore, we should do the same thing for RM_ADDR, clear rm_addr in
>>> mptcp_established_options_rm_addr too.
>>>
>>> If so, patch 1 will become useless. Let's drop it.
>>>
>>> -Geliang
>>> I think RM_ADDR doesn't have this issue. Because mptcp_pm_rm_addr_signal() check the failed case.
> 
> If so, how about doing the same thing as RM_ADDR to check the failed case
> in mptcp_pm_add_addr_signal too.
> 
> I think we should use the same logic for ADD_ADDR and RM_ADDR.

Agree. I will prepare next patch.

> 
>>
>>>
>>>
>>>>>
>>>>> -Geliang
>>>>>
>>>>>>
>>>>>>>
>>>>>>>> +
>>>>>>>> +       pr_debug("addr_signal:%x, echo=%d, local_addr_id=%d, ahmac=%llu, local_port=%d, remote_addr_id=%d, remote_port=%d",
>>>>>>>> +                add_addr, (opts->ahmac == 0), opts->local.id,
>>>>>>>> +                opts->ahmac, ntohs(opts->local.port), opts->remote.id, ntohs(opts->remote.port));
>>>>>>>>
>>>>>>>>         return true;
>>>>>>>>  }
>>>>>>>
>>>>>>> The whole function is something like this:
>>>>>>> '''
>>>>>>>         struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
>>>>>>>         struct mptcp_sock *msk = mptcp_sk(subflow->conn);
>>>>>>>         bool drop_other_suboptions = false;
>>>>>>>         unsigned int opt_size = *size;
>>>>>>>         int len;
>>>>>>>
>>>>>>>         if (!mptcp_pm_should_add_signal(msk) ||
>>>>>>>             !mptcp_pm_add_addr_signal(msk, remaining, opts))
>>>>>>>                 return false;
>>>>>>>
>>>>>>>         if ((mptcp_pm_should_add_signal_echo(msk) ||
>>>>>>>              (mptcp_pm_should_add_signal_addr(msk) &&
>>>>>>>               (opts->local.family == AF_INET6 || opts->local.port))) &&
>>>>>>>             skb && skb_is_tcp_pure_ack(skb)) {
>>>>>>>                 pr_debug("drop other suboptions");
>>>>>>>                 opts->suboptions = 0;
>>>>>>>                 opts->ext_copy.use_ack = 0;
>>>>>>>                 opts->ext_copy.use_map = 0;
>>>>>>>                 remaining += opt_size;
>>>>>>>                 drop_other_suboptions = true;
>>>>>>>         }
>>>>>>>
>>>>>>>         len = mptcp_add_addr_len(opts);
>>>>>>>         if (remaining < len)
>>>>>>>                 return false;
>>>>>>>
>>>>>>>         *size = len;
>>>>>>>         if (drop_other_suboptions)
>>>>>>>                 *size -= opt_size;
>>>>>>>         opts->suboptions |= OPTION_MPTCP_ADD_ADDR;
>>>>>>>         if (mptcp_pm_should_add_signal_addr(msk)) {
>>>>>>>                 opts->ahmac = add_addr_generate_hmac(msk->local_key,
>>>>>>>                                                      msk->remote_key,
>>>>>>>                                                      &opts->local);
>>>>>>>         }
>>>>>>>
>>>>>>>         pr_debug("addr_signal:%x, echo=%d, local_addr_id=%d,
>>>>>>> ahmac=%llu, local_port=%d, remote_addr_id=%d, remote_port=%d",
>>>>>>>                  msk->pm.addr_signal, (opts->ahmac == 0), opts->local.id,
>>>>>>>                  opts->ahmac, ntohs(opts->local.port),
>>>>>>> opts->remote.id, ntohs(opts->remote.port));
>>>>>>>
>>>>>>>         return true;
>>>>>>> '''
>>>>>>>
>>>>>>>> @@ -1229,15 +1238,19 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
>>>>>>>>
>>>>>>>>  mp_capable_done:
>>>>>>>>         if (OPTION_MPTCP_ADD_ADDR & opts->suboptions) {
>>>>>>>> +               struct mptcp_addr_info *addr = &opts->remote;
>>>>>>>
>>>>>>> We can simplify it like this:
>>>>>>>          struct mptcp_addr_info *addr = opts->ahmac ? &opts->local :
>>>>>>> &opts->remote;
>>>>>>>
>>>>>>>>                 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE;
>>>>>>>>                 u8 echo = MPTCP_ADDR_ECHO;
>>>>>>>>
>>>>>>>> +               if (opts->ahmac)
>>>>>>>> +                       addr = &opts->local;
>>>>>>>
>>>>>>> And this trunk can be dropped.
>>>>>>>
>>>>>>>> +
>>>>>>>>  #if IS_ENABLED(CONFIG_MPTCP_IPV6)
>>>>>>>> -               if (opts->addr.family == AF_INET6)
>>>>>>>> +               if (addr->family == AF_INET6)
>>>>>>>>                         len = TCPOLEN_MPTCP_ADD_ADDR6_BASE;
>>>>>>>>  #endif
>>>>>>>>
>>>>>>>> -               if (opts->addr.port)
>>>>>>>> +               if (addr->port)
>>>>>>>>                         len += TCPOLEN_MPTCP_PORT_LEN;
>>>>>>>>
>>>>>>>>                 if (opts->ahmac) {
>>>>>>>> @@ -1246,25 +1259,25 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
>>>>>>>>                 }
>>>>>>>>
>>>>>>>>                 *ptr++ = mptcp_option(MPTCPOPT_ADD_ADDR,
>>>>>>>> -                                     len, echo, opts->addr.id);
>>>>>>>> -               if (opts->addr.family == AF_INET) {
>>>>>>>> -                       memcpy((u8 *)ptr, (u8 *)&opts->addr.addr.s_addr, 4);
>>>>>>>> +                                     len, echo, addr->id);
>>>>>>>> +               if (addr->family == AF_INET) {
>>>>>>>> +                       memcpy((u8 *)ptr, (u8 *)&addr->addr.s_addr, 4);
>>>>>>>>                         ptr += 1;
>>>>>>>>                 }
>>>>>>>>  #if IS_ENABLED(CONFIG_MPTCP_IPV6)
>>>>>>>> -               else if (opts->addr.family == AF_INET6) {
>>>>>>>> -                       memcpy((u8 *)ptr, opts->addr.addr6.s6_addr, 16);
>>>>>>>> +               else if (addr->family == AF_INET6) {
>>>>>>>> +                       memcpy((u8 *)ptr, addr->addr6.s6_addr, 16);
>>>>>>>>                         ptr += 4;
>>>>>>>>                 }
>>>>>>>>  #endif
>>>>>>>>
>>>>>>>> -               if (!opts->addr.port) {
>>>>>>>> +               if (!addr->port) {
>>>>>>>>                         if (opts->ahmac) {
>>>>>>>>                                 put_unaligned_be64(opts->ahmac, ptr);
>>>>>>>>                                 ptr += 2;
>>>>>>>>                         }
>>>>>>>>                 } else {
>>>>>>>> -                       u16 port = ntohs(opts->addr.port);
>>>>>>>> +                       u16 port = ntohs(addr->port);
>>>>>>>>
>>>>>>>>                         if (opts->ahmac) {
>>>>>>>>                                 u8 *bptr = (u8 *)ptr;
>>>>>>>> diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
>>>>>>>> index cf873e9..9c621293 100644
>>>>>>>> --- a/net/mptcp/pm.c
>>>>>>>> +++ b/net/mptcp/pm.c
>>>>>>>> @@ -253,32 +253,25 @@ void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup)
>>>>>>>>
>>>>>>>>  /* path manager helpers */
>>>>>>>>
>>>>>>>> -bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
>>>>>>>> -                             struct mptcp_addr_info *saddr, bool *echo, bool *port)
>>>>>>>> +bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, struct mptcp_out_options *opts,
>>>>>>>> +                             u8 *add_addr)
>>>>>>>
>>>>>>> Drop this add_addr argument.
>>>>>>>
>>>>>>>>  {
>>>>>>>> -       u8 add_addr;
>>>>>>>> -       int ret = false;
>>>>>>>> -
>>>>>>>>         spin_lock_bh(&msk->pm.lock);
>>>>>>>>
>>>>>>>> -       /* double check after the lock is acquired */
>>>>>>>> -       if (!mptcp_pm_should_add_signal(msk))
>>>>>>>> -               goto out_unlock;
>>>>>>>
>>>>>>> Keep this double check code.
>>>>>>>
>>>>>>>> -
>>>>>>>> -       *echo = mptcp_pm_should_add_signal_echo(msk);
>>>>>>>> -       *port = mptcp_pm_should_add_signal_port(msk);
>>>>>>>> -
>>>>>>>> -       if (remaining < mptcp_add_addr_len(msk->pm.local.family, *echo, *port))
>>>>>>>> -               goto out_unlock;
>>>>>>>
>>>>>>> Keep this length double check code too.
>>>>>>>
>>>>>>>> +       if (!mptcp_pm_should_add_signal(msk)) {
>>>>>>>> +               spin_unlock_bh(&msk->pm.lock);
>>>>>>>> +               return false;
>>>>>>>> +       }
>>>>>>>>
>>>>>>>> -       *saddr = msk->pm.local;
>>>>>>>> -       add_addr = msk->pm.addr_signal & ~(BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO));
>>>>>>> -       WRITE_ONCE(msk->pm.addr_signal, add_addr);
>>>>>>>
>>>>>>> This code is just added in patch 1, I think we should keep it. And no need
>>>>>>> to write addr_signal again in mptcp_established_options_add_addr.
>>>>>>>
>>>>>>>> -       ret = true;
>>>>>>>> +       opts->local = msk->pm.local;
>>>>>>>> +       opts->remote = msk->pm.remote;
>>>>>>>> +       *add_addr = msk->pm.addr_signal;
>>>>>>>>
>>>>>>>> -out_unlock:
>>>>>>>>         spin_unlock_bh(&msk->pm.lock);
>>>>>>>> -       return ret;
>>>>>>>
>>>>>>> Keep this out_unlock code.
>>>>>>>
>>>>>>>> +
>>>>>>>> +       if ((mptcp_pm_should_add_signal_echo(msk)) && (mptcp_pm_should_add_signal_addr(msk)))
>>>>>>>> +               mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_SEND_ACK);
>>>>>>>
>>>>>>> Could we use mptcp_pm_add_addr_send_ack here instead of open coding?
>>>>>>>
>>>>>>> I'm no sure why we need this two lines, and why you use '&&' here. Do you
>>>>>>> mean set MPTCP_ADD_ADDR_SIGNAL and MPTCP_ADD_ADDR_ECHO at the same time?
> 
> Please move these two lines into a new patch, and describe why we need it
> in the commit log.
> 
> Thanks.
> -Geliang
> 
>>>>>>>
>>>>>>>> +       return true;
>>>>>>>>  }
>>>>>>>
>>>>>>> The whole function is something like this:
>>>>>>> '''
>>>>>>>         int ret = false;
>>>>>>>         u8 add_addr;
>>>>>>>
>>>>>>>         spin_lock_bh(&msk->pm.lock);
>>>>>>>
>>>>>>>         /* double check after the lock is acquired */
>>>>>>>         if (!mptcp_pm_should_add_signal(msk))
>>>>>>>                 goto out_unlock;
>>>>>>>
>>>>>>>         if (remaining < mptcp_add_addr_len(opts))
>>>>>>>                 goto out_unlock;
>>>>>>>
>>>>>>>         opts->local = msk->pm.local;
>>>>>>>         opts->remote = msk->pm.remote;
>>>>>>>         if (mptcp_pm_should_add_signal_echo(msk))
>>>>>>>                 add_addr = msk->pm.addr_signal & ~BIT(MPTCP_ADD_ADDR_ECHO);
>>>>>>>         else
>>>>>>>                 add_addr = msk->pm.addr_signal & ~BIT(MPTCP_ADD_ADDR_SIGNAL);
>>>>>>>         WRITE_ONCE(msk->pm.addr_signal, add_addr);
>>>>>>>         ret = true;
>>>>>>>
>>>>>>> out_unlock:
>>>>>>>         spin_unlock_bh(&msk->pm.lock);
>>>>>>>         if (ret && mptcp_pm_should_add_signal_echo(msk) &&
>>>>>>> mptcp_pm_should_add_signal_addr(msk))
>>>>>>>                 mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_SEND_ACK);
>>>>>>>         return ret;
>>>>>>> '''
>>>>>>>
>>>>>>>>
>>>>>>>>  bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
>>>>>>>> diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
>>>>>>>> index a0b0ec0..0bfbbdef 100644
>>>>>>>> --- a/net/mptcp/protocol.h
>>>>>>>> +++ b/net/mptcp/protocol.h
>>>>>>>> @@ -737,16 +737,23 @@ static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk)
>>>>>>>>         return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL);
>>>>>>>>  }
>>>>>>>>
>>>>>>>> -static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port)
>>>>>>>> +static inline unsigned int mptcp_add_addr_len(struct mptcp_out_options *opts)
>>>>>>>>  {
>>>>>>>> -       u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE;
>>>>>>>> +       u8 len = 0;
>>>>>>>> +       struct mptcp_addr_info *addr = &opts->remote;
>>>>>>>
>>>>>>> We can simplify it like this:
>>>>>>>          struct mptcp_addr_info *addr = opts->ahmac ? &opts->local :
>>>>>>> &opts->remote;
>>>>>>>
>>>>>>> And keep the orignal code unchanged.
>>>>>>>
>>>>>>>>
>>>>>>>> -       if (family == AF_INET6)
>>>>>>>> -               len = TCPOLEN_MPTCP_ADD_ADDR6_BASE;
>>>>>>>> -       if (!echo)
>>>>>>>> +       if (opts->ahmac) {
>>>>>>>> +               addr = &opts->local;
>>>>>>>>                 len += MPTCPOPT_THMAC_LEN;
>>>>>>>> +       }
>>>>>>>> +
>>>>>>>> +       if (addr->family == AF_INET6)
>>>>>>>> +               len += TCPOLEN_MPTCP_ADD_ADDR6_BASE;
>>>>>>>> +       else
>>>>>>>> +               len += TCPOLEN_MPTCP_ADD_ADDR_BASE;
>>>>>>>> +
>>>>>>>>         /* account for 2 trailing 'nop' options */
>>>>>>>> -       if (port)
>>>>>>>> +       if (addr->port)
>>>>>>>>                 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN;
>>>>>>>>
>>>>>>>>         return len;
>>>>>>>
>>>>>>> The whole function is something like this:
>>>>>>> '''
>>>>>>>         struct mptcp_addr_info *addr = opts->ahmac ? &opts->local :
>>>>>>> &opts->remote;
>>>>>>>         u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE;
>>>>>>>
>>>>>>>         if (addr->family == AF_INET6)
>>>>>>>                 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE;
>>>>>>>         if (opts->ahmac)
>>>>>>>                 len += MPTCPOPT_THMAC_LEN;
>>>>>>>         /* account for 2 trailing 'nop' options */
>>>>>>>         if (addr->port)
>>>>>>>                 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN;
>>>>>>>
>>>>>>>         return len;
>>>>>>> '''
>>>>>>>
>>>>>>> Thanks.
>>>>>>> -Geliang
>>>>>>>
>>>>>>>> @@ -760,8 +767,8 @@ static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list)
>>>>>>>>         return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1;
>>>>>>>>  }
>>>>>>>>
>>>>>>>> -bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
>>>>>>>> -                             struct mptcp_addr_info *saddr, bool *echo, bool *port);
>>>>>>>> +bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, struct mptcp_out_options *opts,
>>>>>>>> +                             u8 *add_addr);
>>>>>>>>  bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
>>>>>>>>                              struct mptcp_rm_list *rm_list);
>>>>>>>>  int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
>>>>>>>> --
>>>>>>>> 1.8.3.1
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> --
>>>>>> Li YongLong
>>>>>
>>>>
>>>> --
>>>> Li YongLong
>>>>
>>>
>>
>> --
>> Li YongLong
> 

-- 
Li YongLong