From 7b84ab85b12648bc27016088776bbd075e022be3 Mon Sep 17 00:00:00 2001 From: Tong Zhang Date: Fri, 29 Jul 2022 20:33:24 -0700 Subject: [PATCH] staging: rtl8192u: fix rmmod warn when device is renamed This driver creates 4 debug files under [devname] folder. The devname could be wlan0 initially, however it could be renamed later to e.g. enx00e04c00000. This will cause problem during debug file teardown since it uses netdev->name, which is no longer wlan0. To solve this problem, add a notifier to handle device renaming. Also note that we cannot simply do debugfs_lookup to find out old dentry since by the time the notifier is called, netdev->name is already changed to new name. Reported-by: Zheyu Ma Tested-by: Zheyu Ma Reviewed-by: Dan Carpenter Signed-off-by: Tong Zhang Link: https://lore.kernel.org/r/20220730033335.74153-5-ztong0001@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/staging/rtl8192u/r8192U.h | 1 + drivers/staging/rtl8192u/r8192U_core.c | 32 +++++++++++++++++++++++ drivers/staging/rtl8192u/r8192U_debugfs.c | 8 ++++++ 3 files changed, 41 insertions(+) diff --git a/drivers/staging/rtl8192u/r8192U.h b/drivers/staging/rtl8192u/r8192U.h index 75f312e41a926..ff0ada00bf414 100644 --- a/drivers/staging/rtl8192u/r8192U.h +++ b/drivers/staging/rtl8192u/r8192U.h @@ -1122,6 +1122,7 @@ void setKey(struct net_device *dev, u8 EntryNo, u8 KeyIndex, u16 KeyType, void rtl8192_debugfs_init_one(struct net_device *dev); void rtl8192_debugfs_exit_one(struct net_device *dev); +void rtl8192_debugfs_rename_one(struct net_device *dev); void rtl8192_debugfs_init(void); void rtl8192_debugfs_exit(void); diff --git a/drivers/staging/rtl8192u/r8192U_core.c b/drivers/staging/rtl8192u/r8192U_core.c index 865bc0dc7c71b..0a60ef20107c4 100644 --- a/drivers/staging/rtl8192u/r8192U_core.c +++ b/drivers/staging/rtl8192u/r8192U_core.c @@ -4606,6 +4606,30 @@ static void rtl8192_usb_disconnect(struct usb_interface *intf) RT_TRACE(COMP_DOWN, "wlan driver removed\n"); } +static int rtl8192_usb_netdev_event(struct notifier_block *nb, unsigned long event, + void *data) +{ + struct net_device *netdev = netdev_notifier_info_to_dev(data); + + if (netdev->netdev_ops != &rtl8192_netdev_ops) + goto out; + + switch (event) { + case NETDEV_CHANGENAME: + rtl8192_debugfs_rename_one(netdev); + break; + default: + break; + } + +out: + return NOTIFY_DONE; +} + +static struct notifier_block rtl8192_usb_netdev_notifier = { + .notifier_call = rtl8192_usb_netdev_event, +}; + static int __init rtl8192_usb_module_init(void) { int ret; @@ -4615,6 +4639,12 @@ static int __init rtl8192_usb_module_init(void) RT_TRACE(COMP_INIT, "Initializing module"); RT_TRACE(COMP_INIT, "Wireless extensions version %d", WIRELESS_EXT); + ret = register_netdevice_notifier(&rtl8192_usb_netdev_notifier); + if (ret) { + pr_err("register_netdevice_notifier failed %d\n", ret); + return ret; + } + rtl8192_debugfs_init(); ret = ieee80211_debug_init(); if (ret) { @@ -4663,6 +4693,7 @@ debug_exit: ieee80211_debug_exit(); debugfs_exit: rtl8192_debugfs_exit(); + unregister_netdevice_notifier(&rtl8192_usb_netdev_notifier); return ret; } @@ -4675,6 +4706,7 @@ static void __exit rtl8192_usb_module_exit(void) ieee80211_crypto_deinit(); ieee80211_debug_exit(); rtl8192_debugfs_exit(); + unregister_netdevice_notifier(&rtl8192_usb_netdev_notifier); RT_TRACE(COMP_DOWN, "Exiting"); } diff --git a/drivers/staging/rtl8192u/r8192U_debugfs.c b/drivers/staging/rtl8192u/r8192U_debugfs.c index c645043466578..fe8ef72506ee1 100644 --- a/drivers/staging/rtl8192u/r8192U_debugfs.c +++ b/drivers/staging/rtl8192u/r8192U_debugfs.c @@ -169,6 +169,14 @@ void rtl8192_debugfs_exit_one(struct net_device *dev) debugfs_remove_recursive(priv->debugfs_dir); } +void rtl8192_debugfs_rename_one(struct net_device *dev) +{ + struct r8192_priv *priv = ieee80211_priv(dev); + struct dentry *parent_dir = debugfs_lookup(KBUILD_MODNAME, NULL); + + debugfs_rename(parent_dir, priv->debugfs_dir, parent_dir, dev->name); +} + void rtl8192_debugfs_init(void) { debugfs_create_dir(KBUILD_MODNAME, NULL); -- 2.30.2