1 files changed, 39 insertions, 27 deletions

diff --git a/kernel/trace/kprobe_event_gen_test.c b/kernel/trace/kprobe_event_gen_test.c
index 80e04a1e1977..c736487fc0e4 100644
--- a/kernel/trace/kprobe_event_gen_test.c
+++ b/kernel/trace/kprobe_event_gen_test.c
@@ -73,6 +73,10 @@ static struct trace_event_file *gen_kretprobe_test;
 #define KPROBE_GEN_TEST_ARG3	NULL
 #endif
 
+static bool trace_event_file_is_valid(struct trace_event_file *input)
+{
+	return input && !IS_ERR(input);
+}
 
 /*
  * Test to make sure we can create a kprobe event, then add more
@@ -100,20 +104,20 @@ static int __init test_gen_kprobe_cmd(void)
 					 KPROBE_GEN_TEST_FUNC,
 					 KPROBE_GEN_TEST_ARG0, KPROBE_GEN_TEST_ARG1);
 	if (ret)
-		goto free;
+		goto out;
 
 	/* Use kprobe_event_add_fields to add the rest of the fields */
 
 	ret = kprobe_event_add_fields(&cmd, KPROBE_GEN_TEST_ARG2, KPROBE_GEN_TEST_ARG3);
 	if (ret)
-		goto free;
+		goto out;
 
 	/*
 	 * This actually creates the event.
 	 */
 	ret = kprobe_event_gen_cmd_end(&cmd);
 	if (ret)
-		goto free;
+		goto out;
 
 	/*
 	 * Now get the gen_kprobe_test event file.  We need to prevent
@@ -136,13 +140,13 @@ static int __init test_gen_kprobe_cmd(void)
 		goto delete;
 	}
  out:
+	kfree(buf);
 	return ret;
  delete:
+	if (trace_event_file_is_valid(gen_kprobe_test))
+		gen_kprobe_test = NULL;
 	/* We got an error after creating the event, delete it */
 	ret = kprobe_event_delete("gen_kprobe_test");
- free:
-	kfree(buf);
-
 	goto out;
 }
 
@@ -170,14 +174,14 @@ static int __init test_gen_kretprobe_cmd(void)
 					    KPROBE_GEN_TEST_FUNC,
 					    "$retval");
 	if (ret)
-		goto free;
+		goto out;
 
 	/*
 	 * This actually creates the event.
 	 */
 	ret = kretprobe_event_gen_cmd_end(&cmd);
 	if (ret)
-		goto free;
+		goto out;
 
 	/*
 	 * Now get the gen_kretprobe_test event file.  We need to
@@ -201,13 +205,13 @@ static int __init test_gen_kretprobe_cmd(void)
 		goto delete;
 	}
  out:
+	kfree(buf);
 	return ret;
  delete:
+	if (trace_event_file_is_valid(gen_kretprobe_test))
+		gen_kretprobe_test = NULL;
 	/* We got an error after creating the event, delete it */
 	ret = kprobe_event_delete("gen_kretprobe_test");
- free:
-	kfree(buf);
-
 	goto out;
 }
 
@@ -221,10 +225,12 @@ static int __init kprobe_event_gen_test_init(void)
 
 	ret = test_gen_kretprobe_cmd();
 	if (ret) {
-		WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
-						  "kprobes",
-						  "gen_kretprobe_test", false));
-		trace_put_event_file(gen_kretprobe_test);
+		if (trace_event_file_is_valid(gen_kretprobe_test)) {
+			WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
+							  "kprobes",
+							  "gen_kretprobe_test", false));
+			trace_put_event_file(gen_kretprobe_test);
+		}
 		WARN_ON(kprobe_event_delete("gen_kretprobe_test"));
 	}
 
@@ -233,24 +239,30 @@ static int __init kprobe_event_gen_test_init(void)
 
 static void __exit kprobe_event_gen_test_exit(void)
 {
-	/* Disable the event or you can't remove it */
-	WARN_ON(trace_array_set_clr_event(gen_kprobe_test->tr,
-					  "kprobes",
-					  "gen_kprobe_test", false));
+	if (trace_event_file_is_valid(gen_kprobe_test)) {
+		/* Disable the event or you can't remove it */
+		WARN_ON(trace_array_set_clr_event(gen_kprobe_test->tr,
+						  "kprobes",
+						  "gen_kprobe_test", false));
+
+		/* Now give the file and instance back */
+		trace_put_event_file(gen_kprobe_test);
+	}
 
-	/* Now give the file and instance back */
-	trace_put_event_file(gen_kprobe_test);
 
 	/* Now unregister and free the event */
 	WARN_ON(kprobe_event_delete("gen_kprobe_test"));
 
-	/* Disable the event or you can't remove it */
-	WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
-					  "kprobes",
-					  "gen_kretprobe_test", false));
+	if (trace_event_file_is_valid(gen_kretprobe_test)) {
+		/* Disable the event or you can't remove it */
+		WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
+						  "kprobes",
+						  "gen_kretprobe_test", false));
+
+		/* Now give the file and instance back */
+		trace_put_event_file(gen_kretprobe_test);
+	}
 
-	/* Now give the file and instance back */
-	trace_put_event_file(gen_kretprobe_test);
 
 	/* Now unregister and free the event */
 	WARN_ON(kprobe_event_delete("gen_kretprobe_test"));