netfilter: Make nflog quiet when no one listen in userspace.

netfilter: Make nflog quiet when no one listen in userspace.

[Eric Leblond]

The message "nf_log_packet: can't log since no backend logging module loaded
in! Please either load one, or disable logging explicitly" was displayed for
each logged packet when no userspace application is listening to nflog events.
The message seems to warn for a problem with a kernel module missing but as
said before this is not the case. I thus propose to suppress the message (I
don't see any reason to flood the log because a user application has crashed.)

Signed-off-by: Eric Leblond <eric@inl.fr>
---
 net/netfilter/nf_log.c |    4 ----
 1 files changed, 0 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index bc11d70..9fda6ee 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -92,10 +92,6 @@ void nf_log_packet(int pf,
 		vsnprintf(prefix, sizeof(prefix), fmt, args);
 		va_end(args);
 		logger->logfn(pf, hooknum, skb, in, out, loginfo, prefix);
-	} else if (net_ratelimit()) {
-		printk(KERN_WARNING "nf_log_packet: can\'t log since "
-		       "no backend logging module loaded in! Please either "
-		       "load one, or disable logging explicitly\n");
 	}
 	rcu_read_unlock();
 }
-- 
1.5.4.3

Re: netfilter: Make nflog quiet when no one listen in userspace.

[Patrick McHardy]

Eric Leblond wrote:
> The message "nf_log_packet: can't log since no backend logging module loaded
> in! Please either load one, or disable logging explicitly" was displayed for
> each logged packet when no userspace application is listening to nflog events.
> The message seems to warn for a problem with a kernel module missing but as
> said before this is not the case. I thus propose to suppress the message (I
> don't see any reason to flood the log because a user application has crashed.)

Yes, that message has annoyed me on multiple occasions as well.
Applied, thanks Eric.