Re: [syzbot] Re: [syzbot] [fs?] KASAN: slab-use-after-free Read in debugfs_u32_get

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Subject: Re: [syzbot] [fs?] KASAN: slab-use-after-free Read in debugfs_u32_get
Author: lizhi.xu@windriver.com

#syz test

diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
index 3e0b61202f0c..b679b3bb3459 100644
--- a/drivers/net/netdevsim/dev.c
+++ b/drivers/net/netdevsim/dev.c
@@ -1650,7 +1650,6 @@ static void nsim_dev_reload_destroy(struct nsim_dev *nsim_dev)
 
 	if (devlink_is_reload_failed(devlink))
 		return;
-	debugfs_remove(nsim_dev->take_snapshot);
 
 	if (nsim_dev_get_vfs(nsim_dev)) {
 		nsim_bus_dev_set_vfs(nsim_dev->nsim_bus_dev, 0);
@@ -1665,6 +1664,7 @@ static void nsim_dev_reload_destroy(struct nsim_dev *nsim_dev)
 	nsim_fib_destroy(devlink, nsim_dev->fib_data);
 	nsim_dev_traps_exit(devlink);
 	nsim_dev_dummy_region_exit(nsim_dev);
+	nsim_dev_debugfs_exit(nsim_dev);
 }
 
 void nsim_drv_remove(struct nsim_bus_dev *nsim_bus_dev)
@@ -1676,7 +1676,6 @@ void nsim_drv_remove(struct nsim_bus_dev *nsim_bus_dev)
 	nsim_dev_reload_destroy(nsim_dev);
 
 	nsim_bpf_dev_exit(nsim_dev);
-	nsim_dev_debugfs_exit(nsim_dev);
 	devl_params_unregister(devlink, nsim_devlink_params,
 			       ARRAY_SIZE(nsim_devlink_params));
 	devl_resources_unregister(devlink);