/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/ is in gcc-i686-linux-android 9.
This file is owned by root:root, with mode 0o755.
..
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/ether.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/icmp6.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/if_ether.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/in.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/in6.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/in_systm.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/ip.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/ip6.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/ip_icmp.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/tcp.h
/usr/x86_64-linux-gnu/i686-linux-android/include/netinet/udp.h