net: ipv6: Add extack messages for route add failures

Add messages for non-obvious errors (e.g, no need to add text for malloc
failures or ENODEV failures). This mostly covers the annoying EINVAL errors
Some message strings violate the 80-columns but searchable strings need to
trump that rule.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index c1197e167d3e48754c7dcadd7b220e4b7c0e95ec..deea901746c8570c5e801e40592c91e3b62812e0 100644 (file)
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -498,6 +498,8 @@ static struct fib6_node *fib6_add_1(struct fib6_node *root,
                    !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) {
                        if (!allow_create) {
                                if (replace_required) {
+                                       NL_SET_ERR_MSG(extack,
+                                                      "Can not replace route - no match found");
                                        pr_warn("Can't replace route, no match found\n");
                                        return ERR_PTR(-ENOENT);
                                }
@@ -544,6 +546,8 @@ static struct fib6_node *fib6_add_1(struct fib6_node *root,
                 * That would keep IPv6 consistent with IPv4
                 */
                if (replace_required) {
+                       NL_SET_ERR_MSG(extack,
+                                      "Can not replace route - no match found");
                        pr_warn("Can't replace route, no match found\n");
                        return ERR_PTR(-ENOENT);
                }

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ca754ec4054a1c3dd8152017821e6e52f8a59626..80bda31ffbbe3df1f2dcffb6315a92d73e8a3d90 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1857,14 +1857,25 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
        int err = -EINVAL;
 
        /* RTF_PCPU is an internal flag; can not be set by userspace */
-       if (cfg->fc_flags & RTF_PCPU)
+       if (cfg->fc_flags & RTF_PCPU) {
+               NL_SET_ERR_MSG(extack, "Userspace can not set RTF_PCPU");
                goto out;
+       }
 
-       if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
+       if (cfg->fc_dst_len > 128) {
+               NL_SET_ERR_MSG(extack, "Invalid prefix length");
+               goto out;
+       }
+       if (cfg->fc_src_len > 128) {
+               NL_SET_ERR_MSG(extack, "Invalid source address length");
                goto out;
+       }
 #ifndef CONFIG_IPV6_SUBTREES
-       if (cfg->fc_src_len)
+       if (cfg->fc_src_len) {
+               NL_SET_ERR_MSG(extack,
+                              "Specifying source address requires IPV6_SUBTREES to be enabled");
                goto out;
+       }
 #endif
        if (cfg->fc_ifindex) {
                err = -ENODEV;
@@ -2015,9 +2026,10 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
                err = -EINVAL;
                if (ipv6_chk_addr_and_flags(net, gw_addr,
                                            gwa_type & IPV6_ADDR_LINKLOCAL ?
-                                           dev : NULL, 0, 0))
+                                           dev : NULL, 0, 0)) {
+                       NL_SET_ERR_MSG(extack, "Invalid gateway address");
                        goto out;
-
+               }
                rt->rt6i_gateway = *gw_addr;
 
                if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
@@ -2033,8 +2045,11 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
                           addressing
                         */
                        if (!(gwa_type & (IPV6_ADDR_UNICAST |
-                                         IPV6_ADDR_MAPPED)))
+                                         IPV6_ADDR_MAPPED))) {
+                               NL_SET_ERR_MSG(extack,
+                                              "Invalid gateway address");
                                goto out;
+                       }
 
                        if (cfg->fc_table) {
                                grt = ip6_nh_lookup_table(net, cfg, gw_addr);
@@ -2074,8 +2089,14 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
                                goto out;
                }
                err = -EINVAL;
-               if (!dev || (dev->flags & IFF_LOOPBACK))
+               if (!dev) {
+                       NL_SET_ERR_MSG(extack, "Egress device not specified");
+                       goto out;
+               } else if (dev->flags & IFF_LOOPBACK) {
+                       NL_SET_ERR_MSG(extack,
+                                      "Egress device can not be loopback device for this route");
                        goto out;
+               }
        }
 
        err = -ENODEV;
@@ -2084,6 +2105,7 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
 
        if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
                if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
+                       NL_SET_ERR_MSG(extack, "Invalid source address");
                        err = -EINVAL;
                        goto out;
                }
@@ -2234,8 +2256,10 @@ static int ip6_route_del(struct fib6_config *cfg,
        int err = -ESRCH;
 
        table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
-       if (!table)
+       if (!table) {
+               NL_SET_ERR_MSG(extack, "FIB table does not exist");
                return err;
+       }
 
        read_lock_bh(&table->tb6_lock);