isdn/gigaset: ratelimit CAPI message dumps

commit 8e618aad5348b6e6c5a90e8d97ea643197963b20 upstream.

Introduce a global ratelimit for CAPI message dumps to protect
against possible log flood.
Drop the ratelimit for ignored messages which is now covered by the
global one.

Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 9 insertions, 13 deletions

diff --git a/drivers/isdn/gigaset/capi.c b/drivers/isdn/gigaset/capi.c
index 658e75f18d0..d1dde6577fa 100644
--- a/drivers/isdn/gigaset/capi.c
+++ b/drivers/isdn/gigaset/capi.c
@@ -14,6 +14,7 @@
 #include "gigaset.h"
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
+#include <linux/ratelimit.h>
 #include <linux/isdn/capilli.h>
 #include <linux/isdn/capicmd.h>
 #include <linux/isdn/capiutil.h>
@@ -222,10 +223,14 @@ get_appl(struct gigaset_capi_ctr *iif, u16 appl)
 static inline void dump_cmsg(enum debuglevel level, const char *tag, _cmsg *p)
 {
 #ifdef CONFIG_GIGASET_DEBUG
+        /* dump at most 20 messages in 20 secs */
+        static DEFINE_RATELIMIT_STATE(msg_dump_ratelimit, 20 * HZ, 20);
         _cdebbuf *cdb;
 
         if (!(gigaset_debuglevel & level))
                 return;
+        if (!___ratelimit(&msg_dump_ratelimit, tag))
+                return;
 
         cdb = capi_cmsg2str(p);
         if (cdb) {
@@ -2058,12 +2063,6 @@ static void do_reset_b3_req(struct gigaset_capi_ctr *iif,
 }
 
 /*
- * dump unsupported/ignored messages at most twice per minute,
- * some apps send those very frequently
- */
-static unsigned long ignored_msg_dump_time;
-
-/*
  * unsupported CAPI message handler
  */
 static void do_unsupported(struct gigaset_capi_ctr *iif,
@@ -2072,8 +2071,7 @@ static void do_unsupported(struct gigaset_capi_ctr *iif,
 {
         /* decode message */
         capi_message2cmsg(&iif->acmsg, skb->data);
-        if (printk_timed_ratelimit(&ignored_msg_dump_time, 30 * 1000))
-                dump_cmsg(DEBUG_CMD, __func__, &iif->acmsg);
+        dump_cmsg(DEBUG_CMD, __func__, &iif->acmsg);
         send_conf(iif, ap, skb, CapiMessageNotSupportedInCurrentState);
 }
 
@@ -2084,11 +2082,9 @@ static void do_nothing(struct gigaset_capi_ctr *iif,
                        struct gigaset_capi_appl *ap,
                        struct sk_buff *skb)
 {
-        if (printk_timed_ratelimit(&ignored_msg_dump_time, 30 * 1000)) {
-                /* decode message */
-                capi_message2cmsg(&iif->acmsg, skb->data);
-                dump_cmsg(DEBUG_CMD, __func__, &iif->acmsg);
-        }
+        /* decode message */
+        capi_message2cmsg(&iif->acmsg, skb->data);
+        dump_cmsg(DEBUG_CMD, __func__, &iif->acmsg);
         dev_kfree_skb_any(skb);
 }