rtla/osnoise: Prevent NULL dereference in error handling

commit 90574d2a upstream.

If the "tool->data" allocation fails then there is no need to call
osnoise_free_top() and, in fact, doing so will lead to a NULL dereference.

Cc: stable@vger.kernel.org
Cc: John Kacur <jkacur@redhat.com>
Cc: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Fixes: 1eceb2fc ("rtla/osnoise: Add osnoise top mode")
Link: https://lore.kernel.org/f964ed1f-64d2-4fde-ad3e-708331f8f358@stanley.mountain


Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tools/tracing/rtla/src/osnoise_top.c

@@ -520,8 +520,10 @@ struct osnoise_tool *osnoise_init_top(struct osnoise_top_params *params)
 		return NULL;
 
 	tool->data = osnoise_alloc_top(nr_cpus);
-	if (!tool->data)
-		goto out_err;
+	if (!tool->data) {
+		osnoise_destroy_tool(tool);
+		return NULL;
+	}
 
 	tool->params = params;
 
@@ -529,11 +531,6 @@ struct osnoise_tool *osnoise_init_top(struct osnoise_top_params *params)
 				   osnoise_top_handler, NULL);
 
 	return tool;
-
-out_err:
-	osnoise_free_top(tool->data);
-	osnoise_destroy_tool(tool);
-	return NULL;
 }
 
 static int stop_tracing;