system-linux: Don't set gre tunnel ttl by default to 64 (#FS312)

[project/netifd.git] / system-linux.c

diff --git a/system-linux.c b/system-linux.c
index 67fa2b1..52a1c17 100644 (file)
--- a/system-linux.c
+++ b/system-linux.c
@@ -2127,7 +2127,7 @@ static int system_add_gre_tunnel(const char *name, const char *kind,
        uint32_t ikey = 0, okey = 0, flags = 0, flowinfo = 0;
        uint16_t iflags = 0, oflags = 0;
        uint8_t tos = 0;
-       int ret = 0, ttl = 64;
+       int ret = 0, ttl = 0;
 
        nlm = nlmsg_alloc_simple(RTM_NEWLINK, NLM_F_REQUEST | NLM_F_REPLACE | NLM_F_CREATE);
        if (!nlm)
@@ -2155,8 +2155,6 @@ static int system_add_gre_tunnel(const char *name, const char *kind,
        if ((cur = tb[TUNNEL_ATTR_TTL]))
                ttl = blobmsg_get_u32(cur);
 
-       nla_put_u8(nlm, IFLA_GRE_TTL, ttl);
-
        if ((cur = tb[TUNNEL_ATTR_TOS])) {
                char *str = blobmsg_get_string(cur);
                if (strcmp(str, "inherit")) {
@@ -2230,6 +2228,9 @@ static int system_add_gre_tunnel(const char *name, const char *kind,
 
                if (flags)
                        nla_put_u32(nlm, IFLA_GRE_FLAGS, flags);
+
+               if (!ttl)
+                       ttl = 64;
        } else {
                struct in_addr inbuf;
                bool set_df = true;
@@ -2265,17 +2266,23 @@ static int system_add_gre_tunnel(const char *name, const char *kind,
                if ((cur = tb[TUNNEL_ATTR_DF]))
                        set_df = blobmsg_get_bool(cur);
 
-               /* ttl !=0 and nopmtudisc are incompatible */
-               if (ttl && !set_df) {
-                       ret = -EINVAL;
-                       goto failure;
-               }
+               if (!set_df) {
+                       /* ttl != 0 and nopmtudisc are incompatible */
+                       if (ttl) {
+                               ret = -EINVAL;
+                               goto failure;
+                       }
+               } else if (!ttl)
+                       ttl = 64;
 
                nla_put_u8(nlm, IFLA_GRE_PMTUDISC, set_df ? 1 : 0);
 
                nla_put_u8(nlm, IFLA_GRE_TOS, tos);
        }
 
+       if (ttl)
+               nla_put_u8(nlm, IFLA_GRE_TTL, ttl);
+
        if (oflags)
                nla_put_u16(nlm, IFLA_GRE_OFLAGS, oflags);