tracing: Fix failure path in ftrace_graph_write()

Don't call trace_parser_put() on uninitialized trace_parser.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4AB86639.3000003@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index a8fe4782ebad3098979ccf7d287be6aa90e3d2be..5c5cb9be8e8c44ca9752dc5acb940e81335ddcf8 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2561,12 +2561,12 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
 
        if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) {
                ret = -EBUSY;
-               goto out;
+               goto out_unlock;
        }
 
        if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
                ret = -ENOMEM;
-               goto out;
+               goto out_unlock;
        }
 
        read = trace_get_user(&parser, ubuf, cnt, ppos);
@@ -2578,12 +2578,14 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
                ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
                                        parser.buffer);
                if (ret)
-                       goto out;
+                       goto out_free;
        }
 
        ret = read;
- out:
+
+out_free:
        trace_parser_put(&parser);
+out_unlock:
        mutex_unlock(&graph_lock);
 
        return ret;