Merge tag 'trace-v6.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:
 "A couple of fixes for tracing:

   - Prevent a NULL pointer dereference in the error path of RTLA tool

   - Fix an infinite loop bug when reading from the ring buffer when
     closed. If there's a thread trying to read the ring buffer and it
     gets closed by another thread, the one reading will go into an
     infinite loop when the buffer is empty instead of exiting back to
     user space"

* tag 'trace-v6.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  rtla/osnoise: Prevent NULL dereference in error handling
  tracing: Return from tracing_buffers_read() if the file has been closed

Author: torvalds

kernel/trace/trace.c

@@ -7956,7 +7956,7 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
 	trace_access_unlock(iter->cpu_file);
 
 	if (ret < 0) {
-		if (trace_empty(iter)) {
+		if (trace_empty(iter) && !iter->closed) {
 			if ((filp->f_flags & O_NONBLOCK))
 				return -EAGAIN;
 

tools/tracing/rtla/src/osnoise_top.c

@@ -651,20 +651,17 @@ 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;
 
 	tep_register_event_handler(tool->trace.tep, -1, "ftrace", "osnoise",
 				   osnoise_top_handler, NULL);
 
 	return tool;
-
-out_err:
-	osnoise_free_top(tool->data);
-	osnoise_destroy_tool(tool);
-	return NULL;
 }
 
 static int stop_tracing;