ipv4: Stop using NLA_PUT*().

These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 26 insertions, 21 deletions

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index a8c5c1d6715b..63aa48acc98a 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -932,33 +932,36 @@ int fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
                 rtm->rtm_table = tb_id;
         else
                 rtm->rtm_table = RT_TABLE_COMPAT;
-        NLA_PUT_U32(skb, RTA_TABLE, tb_id);
+        if (nla_put_u32(skb, RTA_TABLE, tb_id))
+                goto nla_put_failure;
         rtm->rtm_type = type;
         rtm->rtm_flags = fi->fib_flags;
         rtm->rtm_scope = fi->fib_scope;
         rtm->rtm_protocol = fi->fib_protocol;
 
-        if (rtm->rtm_dst_len)
-                NLA_PUT_BE32(skb, RTA_DST, dst);
-
-        if (fi->fib_priority)
-                NLA_PUT_U32(skb, RTA_PRIORITY, fi->fib_priority);
-
+        if (rtm->rtm_dst_len &&
+            nla_put_be32(skb, RTA_DST, dst))
+                goto nla_put_failure;
+        if (fi->fib_priority &&
+            nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority))
+                goto nla_put_failure;
         if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
                 goto nla_put_failure;
 
-        if (fi->fib_prefsrc)
-                NLA_PUT_BE32(skb, RTA_PREFSRC, fi->fib_prefsrc);
-
+        if (fi->fib_prefsrc &&
+            nla_put_be32(skb, RTA_PREFSRC, fi->fib_prefsrc))
+                goto nla_put_failure;
         if (fi->fib_nhs == 1) {
-                if (fi->fib_nh->nh_gw)
-                        NLA_PUT_BE32(skb, RTA_GATEWAY, fi->fib_nh->nh_gw);
-
-                if (fi->fib_nh->nh_oif)
-                        NLA_PUT_U32(skb, RTA_OIF, fi->fib_nh->nh_oif);
+                if (fi->fib_nh->nh_gw &&
+                    nla_put_be32(skb, RTA_GATEWAY, fi->fib_nh->nh_gw))
+                        goto nla_put_failure;
+                if (fi->fib_nh->nh_oif &&
+                    nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif))
+                        goto nla_put_failure;
 #ifdef CONFIG_IP_ROUTE_CLASSID
-                if (fi->fib_nh[0].nh_tclassid)
-                        NLA_PUT_U32(skb, RTA_FLOW, fi->fib_nh[0].nh_tclassid);
+                if (fi->fib_nh[0].nh_tclassid &&
+                    nla_put_u32(skb, RTA_FLOW, fi->fib_nh[0].nh_tclassid))
+                        goto nla_put_failure;
 #endif
         }
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
@@ -979,11 +982,13 @@ int fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
                         rtnh->rtnh_hops = nh->nh_weight - 1;
                         rtnh->rtnh_ifindex = nh->nh_oif;
 
-                        if (nh->nh_gw)
-                                NLA_PUT_BE32(skb, RTA_GATEWAY, nh->nh_gw);
+                        if (nh->nh_gw &&
+                            nla_put_be32(skb, RTA_GATEWAY, nh->nh_gw))
+                                goto nla_put_failure;
 #ifdef CONFIG_IP_ROUTE_CLASSID
-                        if (nh->nh_tclassid)
-                                NLA_PUT_U32(skb, RTA_FLOW, nh->nh_tclassid);
+                        if (nh->nh_tclassid &&
+                            nla_put_u32(skb, RTA_FLOW, nh->nh_tclassid))
+                                goto nla_put_failure;
 #endif
                         /* length of rtnetlink header + attributes */
                         rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *) rtnh;