tracing: Check return value of tracing_init_dentry()

Check return value and bail out if it's NULL.

Link: http://lkml.kernel.org/r/1365553093-10180-2-git-send-email-namhyung@kernel.org

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: stable@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

3 files changed, 6 insertions, 0 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 07860b995752..72970793b40a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5953,6 +5953,8 @@ static __init int tracer_init_debugfs(void)
         trace_access_lock_init();
 
         d_tracer = tracing_init_dentry();
+        if (!d_tracer)
+                return 0;
 
         init_tracer_debugfs(&global_trace, d_tracer);
 
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index aab277b67fa9..8c3f37e2dc43 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -431,6 +431,8 @@ static __init int stack_trace_init(void)
         struct dentry *d_tracer;
 
         d_tracer = tracing_init_dentry();
+        if (!d_tracer)
+                return 0;
 
         trace_create_file("stack_max_size", 0644, d_tracer,
                         &max_stack_size, &stack_max_size_fops);
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index 96cffb269e73..847f88a6194b 100644
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -307,6 +307,8 @@ static int tracing_stat_init(void)
         struct dentry *d_tracing;
 
         d_tracing = tracing_init_dentry();
+        if (!d_tracing)
+                return 0;
 
         stat_dir = debugfs_create_dir("trace_stat", d_tracing);
         if (!stat_dir)