From: Yasuyuki Kozakai Date: Sun, 8 Jul 2007 05:40:08 +0000 (-0700) Subject: [NETFILTER]: nfnetlink_queue: don't unregister handler of other subsystem X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=ce7663d84a87bb4e1743f62950bf7dceed723a13;p=linux-beck.git [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 --- diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index 10b5c6275706..0eed0b7ab2df 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -275,7 +275,8 @@ struct nf_queue_handler { }; extern int nf_register_queue_handler(int pf, struct nf_queue_handler *qh); -extern int nf_unregister_queue_handler(int pf); +extern int nf_unregister_queue_handler(int pf, + struct nf_queue_handler *qh); extern void nf_unregister_queue_handlers(struct nf_queue_handler *qh); extern void nf_reinject(struct sk_buff *skb, struct nf_info *info, diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c index b1f2ace96f6d..f402894d7e72 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 7a97bec67729..7d47fc4b19c6 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;