From ce7663d84a87bb4e1743f62950bf7dceed723a13 Mon Sep 17 00:00:00 2001 From: Yasuyuki Kozakai Date: Sat, 7 Jul 2007 22:40:08 -0700 Subject: [NETFILTER]: nfnetlink_queue: don't unregister handler of other subsystem The queue handlers registered by ip[6]_queue.ko at initialization should not be unregistered according to requests from userland program using nfnetlink_queue. If we allow that, there is no way to register the handlers of built-in ip[6]_queue again. Signed-off-by: Yasuyuki Kozakai Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/netfilter/nf_queue.c | 7 ++++++- net/netfilter/nfnetlink_queue.c | 4 +--- 2 files changed, 7 insertions(+), 4 deletions(-) (limited to 'net') diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c index b1f2ace96f6..f402894d7e7 100644 --- a/net/netfilter/nf_queue.c +++ b/net/netfilter/nf_queue.c @@ -44,12 +44,17 @@ int nf_register_queue_handler(int pf, struct nf_queue_handler *qh) EXPORT_SYMBOL(nf_register_queue_handler); /* The caller must flush their queue before this */ -int nf_unregister_queue_handler(int pf) +int nf_unregister_queue_handler(int pf, struct nf_queue_handler *qh) { if (pf >= NPROTO) return -EINVAL; write_lock_bh(&queue_handler_lock); + if (queue_handler[pf] != qh) { + write_unlock_bh(&queue_handler_lock); + return -EINVAL; + } + queue_handler[pf] = NULL; write_unlock_bh(&queue_handler_lock); diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c index 7a97bec6772..7d47fc4b19c 100644 --- a/net/netfilter/nfnetlink_queue.c +++ b/net/netfilter/nfnetlink_queue.c @@ -913,9 +913,7 @@ nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb, case NFQNL_CFG_CMD_PF_UNBIND: QDEBUG("unregistering queue handler for pf=%u\n", ntohs(cmd->pf)); - /* This is a bug and a feature. We can unregister - * other handlers(!) */ - ret = nf_unregister_queue_handler(ntohs(cmd->pf)); + ret = nf_unregister_queue_handler(ntohs(cmd->pf), &nfqh); break; default: ret = -EINVAL; -- cgit v1.2.3