linux-kernel - [PATCH] tracing/trace: apply filters on all output channels

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210814034538.8428-1-kernelfans@gmail.com>
Date:   Sat, 14 Aug 2021 11:45:38 +0800
From:   Pingfan Liu <kernelfans@...il.com>
To:     linux-kernel@...r.kernel.org
Cc:     Pingfan Liu <kernelfans@...il.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        Ingo Molnar <mingo@...hat.com>
Subject: [PATCH] tracing/trace: apply filters on all output channels

The event filters are not applied on all of the output, which results in
the flood of printk when using tp_printk. Unfolding
event_trigger_unlock_commit_regs() into trace_event_buffer_commit(), so
the filters can be applied on every output.

Signed-off-by: Pingfan Liu <kernelfans@...il.com>
Cc: Steven Rostedt <rostedt@...dmis.org>
Cc: Ingo Molnar <mingo@...hat.com>
To: linux-kernel@...r.kernel.org
---
 kernel/trace/trace.c | 18 +++++++++++++++---
 kernel/trace/trace.h | 32 --------------------------------
 2 files changed, 15 insertions(+), 35 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 33899a71fdc1..a1adb29ef5c1 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2897,14 +2897,26 @@ int tracepoint_printk_sysctl(struct ctl_table *table, int write,
 
 void trace_event_buffer_commit(struct trace_event_buffer *fbuffer)
 {
+	enum event_trigger_type tt = ETT_NONE;
+	struct trace_event_file *file = fbuffer->trace_file;
+
+	if (__event_trigger_test_discard(file, fbuffer->buffer, fbuffer->event,
+			fbuffer->entry, &tt))
+		goto discard;
+
 	if (static_key_false(&tracepoint_printk_key.key))
 		output_printk(fbuffer);
 
 	if (static_branch_unlikely(&trace_event_exports_enabled))
 		ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT);
-	event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer,
-				    fbuffer->event, fbuffer->entry,
-				    fbuffer->trace_ctx, fbuffer->regs);
+
+	trace_buffer_unlock_commit_regs(file->tr, fbuffer->buffer,
+			fbuffer->event, fbuffer->trace_ctx, fbuffer->regs);
+
+discard:
+	if (tt)
+		event_triggers_post_call(file, tt);
+
 }
 EXPORT_SYMBOL_GPL(trace_event_buffer_commit);
 
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index a180abf76d4e..4a0e693000c6 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1389,38 +1389,6 @@ event_trigger_unlock_commit(struct trace_event_file *file,
 		event_triggers_post_call(file, tt);
 }
 
-/**
- * event_trigger_unlock_commit_regs - handle triggers and finish event commit
- * @file: The file pointer associated with the event
- * @buffer: The ring buffer that the event is being written to
- * @event: The event meta data in the ring buffer
- * @entry: The event itself
- * @trace_ctx: The tracing context flags.
- *
- * This is a helper function to handle triggers that require data
- * from the event itself. It also tests the event against filters and
- * if the event is soft disabled and should be discarded.
- *
- * Same as event_trigger_unlock_commit() but calls
- * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
- */
-static inline void
-event_trigger_unlock_commit_regs(struct trace_event_file *file,
-				 struct trace_buffer *buffer,
-				 struct ring_buffer_event *event,
-				 void *entry, unsigned int trace_ctx,
-				 struct pt_regs *regs)
-{
-	enum event_trigger_type tt = ETT_NONE;
-
-	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
-		trace_buffer_unlock_commit_regs(file->tr, buffer, event,
-						trace_ctx, regs);
-
-	if (tt)
-		event_triggers_post_call(file, tt);
-}
-
 #define FILTER_PRED_INVALID	((unsigned short)-1)
 #define FILTER_PRED_IS_RIGHT	(1 << 15)
 #define FILTER_PRED_FOLD	(1 << 15)
-- 
2.29.2