diff options
Diffstat (limited to 'net/ipv6/ip6_flowlabel.c')
| -rw-r--r-- | net/ipv6/ip6_flowlabel.c | 39 |
1 files changed, 31 insertions, 8 deletions
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c index 2f3eb7dc45da..d64b83e85642 100644 --- a/net/ipv6/ip6_flowlabel.c +++ b/net/ipv6/ip6_flowlabel.c @@ -17,6 +17,7 @@ #include <linux/slab.h> #include <linux/export.h> #include <linux/pid_namespace.h> +#include <linux/jump_label_ratelimit.h> #include <net/net_namespace.h> #include <net/sock.h> @@ -53,6 +54,9 @@ static DEFINE_SPINLOCK(ip6_fl_lock); static DEFINE_SPINLOCK(ip6_sk_fl_lock); +DEFINE_STATIC_KEY_DEFERRED_FALSE(ipv6_flowlabel_exclusive, HZ); +EXPORT_SYMBOL(ipv6_flowlabel_exclusive); + #define for_each_fl_rcu(hash, fl) \ for (fl = rcu_dereference_bh(fl_ht[(hash)]); \ fl != NULL; \ @@ -90,6 +94,13 @@ static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label) return fl; } +static bool fl_shared_exclusive(struct ip6_flowlabel *fl) +{ + return fl->share == IPV6_FL_S_EXCL || + fl->share == IPV6_FL_S_PROCESS || + fl->share == IPV6_FL_S_USER; +} + static void fl_free_rcu(struct rcu_head *head) { struct ip6_flowlabel *fl = container_of(head, struct ip6_flowlabel, rcu); @@ -103,8 +114,13 @@ static void fl_free_rcu(struct rcu_head *head) static void fl_free(struct ip6_flowlabel *fl) { - if (fl) - call_rcu(&fl->rcu, fl_free_rcu); + if (!fl) + return; + + if (fl_shared_exclusive(fl) || fl->opt) + static_branch_slow_dec_deferred(&ipv6_flowlabel_exclusive); + + call_rcu(&fl->rcu, fl_free_rcu); } static void fl_release(struct ip6_flowlabel *fl) @@ -240,7 +256,7 @@ static struct ip6_flowlabel *fl_intern(struct net *net, /* Socket flowlabel lists */ -struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label) +struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label) { struct ipv6_fl_socklist *sfl; struct ipv6_pinfo *np = inet6_sk(sk); @@ -250,9 +266,9 @@ struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label) rcu_read_lock_bh(); for_each_sk_fl_rcu(np, sfl) { struct ip6_flowlabel *fl = sfl->fl; - if (fl->label == label) { + + if (fl->label == label && atomic_inc_not_zero(&fl->users)) { fl->lastuse = jiffies; - atomic_inc(&fl->users); rcu_read_unlock_bh(); return fl; } @@ -260,7 +276,7 @@ struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label) rcu_read_unlock_bh(); return NULL; } -EXPORT_SYMBOL_GPL(fl6_sock_lookup); +EXPORT_SYMBOL_GPL(__fl6_sock_lookup); void fl6_free_socklist(struct sock *sk) { @@ -433,10 +449,15 @@ fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, err = -EINVAL; goto done; } + if (fl_shared_exclusive(fl) || fl->opt) + static_branch_deferred_inc(&ipv6_flowlabel_exclusive); return fl; done: - fl_free(fl); + if (fl) { + kfree(fl->opt); + kfree(fl); + } *err_p = err; return NULL; } @@ -618,7 +639,8 @@ int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen) goto done; } fl1 = sfl->fl; - atomic_inc(&fl1->users); + if (!atomic_inc_not_zero(&fl1->users)) + fl1 = NULL; break; } } @@ -853,6 +875,7 @@ int ip6_flowlabel_init(void) void ip6_flowlabel_cleanup(void) { + static_key_deferred_flush(&ipv6_flowlabel_exclusive); del_timer(&ip6_fl_gc_timer); unregister_pernet_subsys(&ip6_flowlabel_net_ops); } |