From 336a3b3ee925362ca720342bbae4f36b2215064a Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 13 Oct 2015 12:47:47 +0200 Subject: [PATCH] netfilter: nfnetlink_log: consolidate check for instance in nfulnl_recv_config() This patch consolidates the check for valid logger instance once we have passed the command handling: The config message that we receive may contain the following info: 1) Command only: We always get a valid instance pointer if we just created it. In case that the instance is being destroyed or the command is unknown, we jump to exit path of nfulnl_recv_config(). This patch doesn't modify this handling. 2) Config only: In this case, the instance must always exist since the user is asking for configuration updates. If the instance doesn't exist this returns -ENODEV. 3) No command and no configs are specified: This case is rare. The user is sending us a config message with neither commands nor config options. In this case, we have to check if the instance exists and bail out otherwise. Before this patch, it was possible to send a config message with no command and no config updates for an unexisting instance without triggering an error. So this is the only case that changes. Signed-off-by: Pablo Neira Ayuso Tested-by: Ken-ichirou MATSUZAWA --- net/netfilter/nfnetlink_log.c | 28 +++++----------------------- 1 file changed, 5 insertions(+), 23 deletions(-) diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index f8d9bd848f79..2002d579c3ba 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -874,16 +874,15 @@ nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb, ret = -ENOTSUPP; break; } + } else if (!inst) { + ret = -ENODEV; + goto out; } if (nfula[NFULA_CFG_MODE]) { - struct nfulnl_msg_config_mode *params; - params = nla_data(nfula[NFULA_CFG_MODE]); + struct nfulnl_msg_config_mode *params = + nla_data(nfula[NFULA_CFG_MODE]); - if (!inst) { - ret = -ENODEV; - goto out; - } nfulnl_set_mode(inst, params->copy_mode, ntohl(params->copy_range)); } @@ -891,41 +890,24 @@ nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb, if (nfula[NFULA_CFG_TIMEOUT]) { __be32 timeout = nla_get_be32(nfula[NFULA_CFG_TIMEOUT]); - if (!inst) { - ret = -ENODEV; - goto out; - } nfulnl_set_timeout(inst, ntohl(timeout)); } if (nfula[NFULA_CFG_NLBUFSIZ]) { __be32 nlbufsiz = nla_get_be32(nfula[NFULA_CFG_NLBUFSIZ]); - if (!inst) { - ret = -ENODEV; - goto out; - } nfulnl_set_nlbufsiz(inst, ntohl(nlbufsiz)); } if (nfula[NFULA_CFG_QTHRESH]) { __be32 qthresh = nla_get_be32(nfula[NFULA_CFG_QTHRESH]); - if (!inst) { - ret = -ENODEV; - goto out; - } nfulnl_set_qthresh(inst, ntohl(qthresh)); } if (nfula[NFULA_CFG_FLAGS]) { u16 flags = ntohs(nla_get_be16(nfula[NFULA_CFG_FLAGS])); - if (!inst) { - ret = -ENODEV; - goto out; - } - if (flags & NFULNL_CFG_F_CONNTRACK && !rcu_access_pointer(nfnl_ct_hook)) { #ifdef CONFIG_MODULES -- 2.20.1