netfilter: nfnetlink_log: fix per-rule qthreshold override

In NFLOG the per-rule qthreshold should overrides per-instance only
it is set. With current code, the per-rule qthreshold is 1 if not set
and it overrides the per-instance qthreshold.

This patch modifies the default xt_NFLOG threshold from 1 to
0. Thus a value of 0 means there is no per-rule setting and the instance
parameter has to apply.
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>

include/linux/netfilter/xt_NFLOG.h

@@ -2,7 +2,7 @@
 #define _XT_NFLOG_TARGET
 
 #define XT_NFLOG_DEFAULT_GROUP		0x1
-#define XT_NFLOG_DEFAULT_THRESHOLD	1
+#define XT_NFLOG_DEFAULT_THRESHOLD	0
 
 #define XT_NFLOG_MASK			0x0
 

net/netfilter/nfnetlink_log.c

@@ -590,8 +590,10 @@ nfulnl_log_packet(u_int8_t pf,
 
 	qthreshold = inst->qthreshold;
 	/* per-rule qthreshold overrides per-instance */
-	if (qthreshold > li->u.ulog.qthreshold)
-		qthreshold = li->u.ulog.qthreshold;
+	if (li->u.ulog.qthreshold)
+		if (qthreshold > li->u.ulog.qthreshold)
+			qthreshold = li->u.ulog.qthreshold;
+
 
 	switch (inst->copy_mode) {
 	case NFULNL_COPY_META: