netfilter: print the list of register loggers

This patch modifies the proc output to add display of registered
loggers. The content of /proc/net/netfilter/nf_log is modified. Instead
of displaying a protocol per line with format:
	proto:logger
it now displays:
	proto:logger (comma_separated_list_of_loggers)
NONE is used as keyword if no logger is used.

Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>

1 files changed, 26 insertions, 2 deletions

diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index a228b5fbcf7c..4fcbcc71aa32 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -154,13 +154,37 @@ static int seq_show(struct seq_file *s, void *v)
 {
         loff_t *pos = v;
         const struct nf_logger *logger;
+        struct nf_logger *t;
+        int ret;
 
         logger = rcu_dereference(nf_loggers[*pos]);
 
         if (!logger)
-                return seq_printf(s, "%2lld NONE\n", *pos);
+                ret = seq_printf(s, "%2lld NONE (", *pos);
+        else
+                ret = seq_printf(s, "%2lld %s (", *pos, logger->name);
+
+        if (ret < 0)
+                return ret;
+
+        mutex_lock(&nf_log_mutex);
+        list_for_each_entry(t, &nf_loggers_l[*pos], list[*pos]) {
+                ret = seq_printf(s, "%s", t->name);
+                if (ret < 0) {
+                        mutex_unlock(&nf_log_mutex);
+                        return ret;
+                }
+                if (&t->list[*pos] != nf_loggers_l[*pos].prev) {
+                        ret = seq_printf(s, ",");
+                        if (ret < 0) {
+                                mutex_unlock(&nf_log_mutex);
+                                return ret;
+                        }
+                }
+        }
+        mutex_unlock(&nf_log_mutex);
 
-        return seq_printf(s, "%2lld %s\n", *pos, logger->name);
+        return seq_printf(s, ")\n");
 }
 
 static const struct seq_operations nflog_seq_ops = {