ipv6: make fib6 serial number per namespace

Try to reduce number of possible fn_sernum mutation by constraining them
to their namespace.

Also remove rt_genid which I forgot to remove in 705f1c869d577c ("ipv6:
remove rt6i_genid").

Cc: YOSHIFUJI Hideaki <hideaki@yoshifuji.org>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 7 insertions, 8 deletions

diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 34f726f59814..e8c4400f23e9 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -766,7 +766,7 @@ static int __net_init inet6_net_init(struct net *net)
         net->ipv6.sysctl.icmpv6_time = 1*HZ;
         net->ipv6.sysctl.flowlabel_consistency = 1;
         net->ipv6.sysctl.auto_flowlabels = 0;
-        atomic_set(&net->ipv6.rt_genid, 0);
+        atomic_set(&net->ipv6.fib6_sernum, 1);
 
         err = ipv6_init_mibs(net);
         if (err)
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index be9cb09b05f7..6f9beb1f2861 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -74,8 +74,6 @@ static int fib6_walk_continue(struct fib6_walker *w);
  *      result of redirects, path MTU changes, etc.
  */
 
-static atomic_t rt_sernum = ATOMIC_INIT(1);
-
 static void fib6_gc_timer_cb(unsigned long arg);
 
 static LIST_HEAD(fib6_walkers);
@@ -95,14 +93,15 @@ static void fib6_walker_unlink(struct fib6_walker *w)
         write_unlock_bh(&fib6_walker_lock);
 }
 
-static int fib6_new_sernum(void)
+static int fib6_new_sernum(struct net *net)
 {
         int new, old;
 
         do {
-                old = atomic_read(&rt_sernum);
+                old = atomic_read(&net->ipv6.fib6_sernum);
                 new = old < INT_MAX ? old + 1 : 1;
-        } while (atomic_cmpxchg(&rt_sernum, old, new) != old);
+        } while (atomic_cmpxchg(&net->ipv6.fib6_sernum,
+                                old, new) != old);
         return new;
 }
 
@@ -841,7 +840,7 @@ int fib6_add(struct fib6_node *root, struct rt6_info *rt, struct nl_info *info,
         int err = -ENOMEM;
         int allow_create = 1;
         int replace_required = 0;
-        int sernum = fib6_new_sernum();
+        int sernum = fib6_new_sernum(info->nl_net);
 
         if (info->nlh) {
                 if (!(info->nlh->nlmsg_flags & NLM_F_CREATE))
@@ -1612,7 +1611,7 @@ static int fib6_update_sernum(struct rt6_info *rt, void *arg)
 
 static void fib6_flush_trees(struct net *net)
 {
-        int new_sernum = fib6_new_sernum();
+        int new_sernum = fib6_new_sernum(net);
 
         fib6_clean_all(net, fib6_update_sernum, &new_sernum);
 }