Tunnel change fails if a tunnel name is not specified while using
'ip -6 tunnel change'. However, no warning message is printed and
no error code is returned.
$ ip -6 tunnel add ip6tnl1 mode ip6gre local fd::1 remote fd::2 tos inherit ttl
127 encaplimit none dev dummy0
$ ip -6 tunnel change dev dummy0 local 2001:1234::1 remote 2001:1234::2
$ ip -6 tunnel show ip6tnl1
ip6tnl1: gre/ipv6 remote fd::2 local fd::1 dev dummy0 encaplimit none hoplimit
127 tclass inherit flowlabel 0x00000 (flowinfo 0x00000000)
This commit checks if tunnel interface name is equal to an empty
string: in this case, it prints a warning message to the user.
It intentionally avoids to return an error to not break existing
script setup.
This is the output after this commit:
$ ip -6 tunnel add ip6tnl1 mode ip6gre local fd::1 remote fd::2 tos inherit ttl
127 encaplimit none dev dummy0
$ ip -6 tunnel change dev dummy0 local 2001:1234::1 remote 2001:1234::2
Tunnel interface name not specified
$ ip -6 tunnel show ip6tnl1
ip6tnl1: gre/ipv6 remote fd::2 local fd::1 dev dummy0 encaplimit none hoplimit
127 tclass inherit flowlabel 0x00000 (flowinfo 0x00000000)
Reviewed-by: Matteo Croce <mcr...@redhat.com>
Signed-off-by: Andrea Claudi <acla...@redhat.com>
---
ip/ip6tunnel.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/ip/ip6tunnel.c b/ip/ip6tunnel.c
index 999408ed801b1..e3da11eb4518e 100644
--- a/ip/ip6tunnel.c
+++ b/ip/ip6tunnel.c
@@ -386,6 +386,9 @@ static int do_add(int cmd, int argc, char **argv)
if (parse_args(argc, argv, cmd, &p) < 0)
return -1;
+ if (!*p.name)
+ fprintf(stderr, "Tunnel interface name not specified\n");
+
if (p.proto == IPPROTO_GRE)
basedev = "ip6gre0";
else if (p.i_flags & VTI_ISVTI)
--
2.20.1
