Hi Xin,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Xin-Long/sctp-Implement-RFC6951-UDP-Encapsulation-of-SCTP/20200929-215159
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 280095713ce244e8dbdfb059cdca695baa72230a
config: c6x-randconfig-r023-20200929 (attached as .config)
compiler: c6x-elf-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/38f71b63a83947b86b356d8af1ba077027d27deb
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Xin-Long/sctp-Implement-RFC6951-UDP-Encapsulation-of-SCTP/20200929-215159
        git checkout 38f71b63a83947b86b356d8af1ba077027d27deb
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=c6x 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from include/net/sctp/checksum.h:27,
                    from net/netfilter/nf_nat_proto.c:16:
   include/net/sctp/sctp.h: In function 'sctp_mtu_payload':
>> include/net/sctp/sctp.h:583:31: error: 'struct net' has no member named 'sctp'; did you mean 'ct'?
     583 |   if (sock_net(&sp->inet.sk)->sctp.udp_port)
         |                               ^~~~
         |                               ct

vim +583 include/net/sctp/sctp.h

   572	
   573	/* Calculate max payload size given a MTU, or the total overhead if
   574	 * given MTU is zero
   575	 */
   576	static inline __u32 sctp_mtu_payload(const struct sctp_sock *sp,
   577					     __u32 mtu, __u32 extra)
   578	{
   579		__u32 overhead = sizeof(struct sctphdr) + extra;
   580	
   581		if (sp) {
   582			overhead += sp->pf->af->net_header_len;
 > 583			if (sock_net(&sp->inet.sk)->sctp.udp_port)
   584				overhead += sizeof(struct udphdr);
   585		} else {
   586			overhead += sizeof(struct ipv6hdr);
   587		}
   588	
   589		if (WARN_ON_ONCE(mtu && mtu <= overhead))
   590			mtu = overhead;
   591	
   592		return mtu ? mtu - overhead : overhead;
   593	}
   594	

---
0-DAY CI Kernel Test Service, Intel Corporation
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