netfilter: use rcu_dereference_protected()
Restore the rcu_dereference() calls in conntrack/expectation notifier
and logger registration/unregistration, but use the _protected variant,
which will be required by the upcoming __rcu annotations.
Based on patch by Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index 908f599..7df37fd 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -35,6 +35,7 @@
/* return EEXIST if the same logger is registred, 0 on success. */
int nf_log_register(u_int8_t pf, struct nf_logger *logger)
{
+ const struct nf_logger *llog;
int i;
if (pf >= ARRAY_SIZE(nf_loggers))
@@ -51,7 +52,9 @@
} else {
/* register at end of list to honor first register win */
list_add_tail(&logger->list[pf], &nf_loggers_l[pf]);
- if (nf_loggers[pf] == NULL)
+ llog = rcu_dereference_protected(nf_loggers[pf],
+ lockdep_is_held(&nf_log_mutex));
+ if (llog == NULL)
rcu_assign_pointer(nf_loggers[pf], logger);
}
@@ -63,11 +66,14 @@
void nf_log_unregister(struct nf_logger *logger)
{
+ const struct nf_logger *c_logger;
int i;
mutex_lock(&nf_log_mutex);
for (i = 0; i < ARRAY_SIZE(nf_loggers); i++) {
- if (nf_loggers[i] == logger)
+ c_logger = rcu_dereference_protected(nf_loggers[i],
+ lockdep_is_held(&nf_log_mutex));
+ if (c_logger == logger)
rcu_assign_pointer(nf_loggers[i], NULL);
list_del(&logger->list[i]);
}