diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c index 31a9d63921d6..e104760f7a67 100644 --- a/net/netfilter/nf_log.c +++ b/net/netfilter/nf_log.c @@ -18,6 +18,8 @@ static struct nf_logger *nf_logging[NPROTO]; /* = NULL */ static DEFINE_SPINLOCK(nf_log_lock); +/* return EBUSY if somebody else is registered, EEXIST if the same logger + * is registred, 0 on success. */ int nf_log_register(int pf, struct nf_logger *logger) { int ret = -EBUSY; @@ -28,7 +30,9 @@ int nf_log_register(int pf, struct nf_logger *logger) if (!nf_logging[pf]) { rcu_assign_pointer(nf_logging[pf], logger); ret = 0; - } + } else if (nf_logging[pf] == logger) + ret = -EEXIST; + spin_unlock(&nf_log_lock); return ret; } diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c index 8a67bde8b640..d10d552d9c40 100644 --- a/net/netfilter/nf_queue.c +++ b/net/netfilter/nf_queue.c @@ -20,6 +20,8 @@ static struct nf_queue_rerouter *queue_rerouter; static DEFINE_RWLOCK(queue_handler_lock); +/* return EBUSY when somebody else is registered, return EEXIST if the + * same handler is registered, return 0 in case of success. */ int nf_register_queue_handler(int pf, struct nf_queue_handler *qh) { int ret; @@ -28,7 +30,9 @@ int nf_register_queue_handler(int pf, struct nf_queue_handler *qh) return -EINVAL; write_lock_bh(&queue_handler_lock); - if (queue_handler[pf]) + if (queue_handler[pf] == qh) + ret = -EEXIST; + else if (queue_handler[pf]) ret = -EBUSY; else { queue_handler[pf] = qh;