ERROR:root:../net/ipv4/udp_offload.c: In function ‘udp_tunnel_gro_rcv’:
../net/ipv4/udp_offload.c:172:16: error: returning ‘struct sk_buff *’ from a function with incompatible return type ‘struct skbuff *’ [-Werror=incompatible-pointer-types]
  172 |         return call_gro_receive_sk(udp_sk(sk)->gro_receive, sk, head, skb);
      |                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../net/ipv4/udp_offload.c: In function ‘udp_gro_receive’:
../net/ipv4/udp_offload.c:786:12: error: assignment to ‘struct sk_buff *’ from incompatible pointer type ‘struct skbuff *’ [-Werror=incompatible-pointer-types]
  786 |         pp = udp_tunnel_gro_rcv(sk, head, skb);
      |            ^
In file included from ../include/linux/seqlock.h:19,
                 from ../include/linux/dcache.h:11,
                 from ../include/linux/fs.h:8,
                 from ../include/linux/highmem.h:5,
                 from ../include/linux/bvec.h:10,
                 from ../include/linux/skbuff.h:17,
                 from ../net/ipv4/udp_offload.c:9:
../net/ipv4/udp_offload.c: In function ‘udpv4_offload_init’:
../net/ipv4/udp_offload.c:936:21: error: ‘udp_tunnel_gro_type_lock’ undeclared (first use in this function); did you mean ‘udp_tunnel_gro_rcv’?
  936 |         mutex_init(&udp_tunnel_gro_type_lock);
      |                     ^~~~~~~~~~~~~~~~~~~~~~~~
../include/linux/mutex.h:64:23: note: in definition of macro ‘mutex_init’
   64 |         __mutex_init((mutex), #mutex, &__key);                          \
      |                       ^~~~~
../net/ipv4/udp_offload.c:936:21: note: each undeclared identifier is reported only once for each function it appears in
  936 |         mutex_init(&udp_tunnel_gro_type_lock);
      |                     ^~~~~~~~~~~~~~~~~~~~~~~~
../include/linux/mutex.h:64:23: note: in definition of macro ‘mutex_init’
   64 |         __mutex_init((mutex), #mutex, &__key);                          \
      |                       ^~~~~
cc1: some warnings being treated as errors
make[5]: *** [../scripts/Makefile.build:207: net/ipv4/udp_offload.o] Error 1
make[5]: *** Waiting for unfinished jobs....
make[4]: *** [../scripts/Makefile.build:465: net/ipv4] Error 2
make[4]: *** Waiting for unfinished jobs....
make[3]: *** [../scripts/Makefile.build:465: net] Error 2
make[2]: *** [/home/kunit/testing/Makefile:1989: .] Error 2
make[1]: *** [/home/kunit/testing/Makefile:251: __sub-make] Error 2
make: *** [Makefile:251: __sub-make] Error 2