From f31e8d4982653b39fe312f9938be0f49dd9ab5fa Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso <pablo@netfilter.org> Date: Thu, 13 Jan 2011 14:19:55 +0100 Subject: [PATCH] netfilter: ctnetlink: fix loop in ctnetlink_get_conntrack() This patch fixes a loop in ctnetlink_get_conntrack() that can be triggered if you use the same socket to receive events and to perform a GET operation. Under heavy load, netlink_unicast() may return -EAGAIN, this error code is reserved in nfnetlink for the module load-on-demand. Instead, we return -ENOBUFS which is the appropriate error code that has to be propagated to user-space. Reported-by: Holger Eitzenberger <holger@eitzenberger.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- net/netfilter/nf_conntrack_netlink.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 5cb8d3027b18..2b7eef37875c 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -972,7 +972,8 @@ ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb, free: kfree_skb(skb2); out: - return err; + /* this avoids a loop in nfnetlink. */ + return err == -EAGAIN ? -ENOBUFS : err; } #ifdef CONFIG_NF_NAT_NEEDED -- GitLab