@@ -72,6 +72,7 @@ struct netns_ipv6 {
struct rt6_statistics *rt6_stats;
struct timer_list ip6_fib_timer;
struct hlist_head *fib_table_hash;
+ spinlock_t fib_table_hash_lock;
struct fib6_table *fib6_main_tbl;
struct list_head fib6_walkers;
rwlock_t fib6_walker_lock;
@@ -249,19 +249,33 @@ static struct fib6_table *fib6_alloc_table(struct net *net, u32 id)
struct fib6_table *fib6_new_table(struct net *net, u32 id)
{
- struct fib6_table *tb;
+ struct fib6_table *tb, *new_tb;
if (id == 0)
id = RT6_TABLE_MAIN;
+
tb = fib6_get_table(net, id);
if (tb)
return tb;
- tb = fib6_alloc_table(net, id);
- if (tb)
- fib6_link_table(net, tb);
+ new_tb = fib6_alloc_table(net, id);
+ if (!new_tb)
+ return NULL;
+
+ spin_lock_bh(&net->ipv6.fib_table_hash_lock);
+
+ tb = fib6_get_table(net, id);
+ if (unlikely(tb)) {
+ spin_unlock_bh(&net->ipv6.fib_table_hash_lock);
+ kfree(new_tb);
+ return tb;
+ }
- return tb;
+ fib6_link_table(net, new_tb);
+
+ spin_unlock_bh(&net->ipv6.fib_table_hash_lock);
+
+ return new_tb;
}
EXPORT_SYMBOL_GPL(fib6_new_table);
@@ -2423,6 +2437,8 @@ static int __net_init fib6_net_init(struct net *net)
if (!net->ipv6.fib_table_hash)
goto out_rt6_stats;
+ spin_lock_init(&net->ipv6.fib_table_hash_lock);
+
net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl),
GFP_KERNEL);
if (!net->ipv6.fib6_main_tbl)
We will get rid of RTNL from RTM_NEWROUTE and SIOCADDRT. If the request specifies a new table ID, fib6_new_table() is called to create a new routing table. Two concurrent requests could specify the same table ID, so we need a lock to protect net->ipv6.fib_table_hash[h]. Let's add a spinlock to protect the hash bucket linkage. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> --- include/net/netns/ipv6.h | 1 + net/ipv6/ip6_fib.c | 26 +++++++++++++++++++++----- 2 files changed, 22 insertions(+), 5 deletions(-)