Re: [syzbot] [kernel?] INFO: trying to register non-static key in waveform_detach

[Hillf Danton <hdanton@sina.com>]

> Date: Mon, 07 Jul 2025 09:31:28 -0700
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    4c06e63b9203 Merge tag 'for-6.16-rc4-tag' of git://git.ker..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=16528f70580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=b29b1a0d7330d4a8
> dashboard link: https://syzkaller.appspot.com/bug?extid=eec47f88bae8951c6afd
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14a66c8c580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11528f70580000

#syz test

--- x/drivers/comedi/drivers.c
+++ y/drivers/comedi/drivers.c
@@ -994,10 +994,13 @@ int comedi_device_attach(struct comedi_d
 	dev->board_name = dev->board_ptr ? *(const char **)dev->board_ptr
 					 : dev->driver->driver_name;
 	ret = driv->attach(dev, it);
-	if (ret >= 0)
+	if (ret >= 0) {
 		ret = comedi_device_postconfig(dev);
-	if (ret < 0) {
-		comedi_device_detach(dev);
+		if (ret < 0) {
+			comedi_device_detach(dev);
+			module_put(driv->module);
+		}
+	} else {
 		module_put(driv->module);
 	}
 	/* On success, the driver module count has been incremented. */
--