WireGuard fails to build on CentOS 7.1908

[Dario Pilori]

Dear all,

I just upgraded a test machine to CentOS 7.1908 (based on RHEL 7.7),
currently on CR repository, which carries Linux kernel 3.10.0-1062.

Latest WireGuard release from CentOS RPM repo (0.0.20190702) fails to
build with the following error:

DKMS make.log for wireguard-0.0.20190702 for kernel
3.10.0-1062.el7.x86_64 (x86_64)
Sat Aug 31 17:51:43 CEST 2019
make: Entering directory `/usr/src/kernels/3.10.0-1062.el7.x86_64'
  LD      /var/lib/dkms/wireguard/0.0.20190702/build/built-in.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20190702/build/main.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20190702/build/noise.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20190702/build/device.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20190702/build/peer.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20190702/build/timers.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20190702/build/queueing.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20190702/build/send.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20190702/build/receive.o
/var/lib/dkms/wireguard/0.0.20190702/build/receive.c: In function
‘wg_packet_consume_data_done’:
/var/lib/dkms/wireguard/0.0.20190702/build/receive.c:403:4: warning:
passing argument 1 of ‘IP6_ECN_set_ce’ from incompatible pointer type
[enabled by default]
    IP6_ECN_set_ce(skb, ipv6_hdr(skb));
    ^
In file included from include/net/ip_tunnels.h:14:0,
                 from
/var/lib/dkms/wireguard/0.0.20190702/build/compat/compat.h:92,
                 from <command-line>:0:
include/net/inet_ecn.h:120:19: note: expected ‘struct sk_buff *’ but
argument is of type ‘struct ipv6hdr *’
 static inline int IP6_ECN_set_ce(struct sk_buff *skb, struct ipv6hdr *iph)
                   ^
/var/lib/dkms/wireguard/0.0.20190702/build/receive.c:403:4: error: too
few arguments to function ‘IP6_ECN_set_ce’
    IP6_ECN_set_ce(skb, ipv6_hdr(skb));
    ^
In file included from include/net/ip_tunnels.h:14:0,
                 from
/var/lib/dkms/wireguard/0.0.20190702/build/compat/compat.h:92,
                 from <command-line>:0:
include/net/inet_ecn.h:120:19: note: declared here
 static inline int IP6_ECN_set_ce(struct sk_buff *skb, struct ipv6hdr *iph)
                   ^
make[1]: *** [/var/lib/dkms/wireguard/0.0.20190702/build/receive.o] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [_module_/var/lib/dkms/wireguard/0.0.20190702/build] Error 2
make: Leaving directory `/usr/src/kernels/3.10.0-1062.el7.x86_64'

I am not sure if this is a known bug or not.

Thanks,
Dario