[PATCH 5.10 012/406] staging: rtl8712: fix race condition

Greg Kroah-Hartman
2023-09-17T19:17:46Z

From: Nam Cao <namcaov@gmail.com>

commit 1422b526fba994cf05fd288a152106563b875fce upstream.

In probe function, request_firmware_nowait() is called to load firmware
asynchronously. At completion of firmware loading, register_netdev() is
called. However, a mutex needed by netdev is initialized after the call
to request_firmware_nowait(). Consequently, it can happen that
register_netdev() is called before the driver is ready.

Move the mutex initialization into r8712_init_drv_sw(), which is called
before request_firmware_nowait().

Reported-by: syzbot+b08315e8cf5a78eed03c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-staging/000000000000d9d4560601b8e0d7@google.com/T/#u
Fixes: 8c213fa59199 ("staging: r8712u: Use asynchronous firmware loading")
Cc: stable <stable@kernel.org>
Signed-off-by: Nam Cao <namcaov@gmail.com>
Link: https://lore.kernel.org/r/20230731110620.116562-1-namcaov@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/staging/rtl8712/os_intfs.c | 1 +
drivers/staging/rtl8712/usb_intf.c | 1 -
2 files changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/staging/rtl8712/os_intfs.c
+++ b/drivers/staging/rtl8712/os_intfs.c
@@ -323,6 +323,7 @@ int r8712_init_drv_sw(struct _adapter *p
mp871xinit(padapter);
init_default_value(padapter);
r8712_InitSwLeds(padapter);
+ mutex_init(&padapter->mutex_start);
return ret;
}

--- a/drivers/staging/rtl8712/usb_intf.c
+++ b/drivers/staging/rtl8712/usb_intf.c
@@ -570,7 +570,6 @@ static int r871xu_drv_init(struct usb_in
if (rtl871x_load_fw(padapter))
goto deinit_drv_sw;
spin_lock_init(&padapter->lock_rx_ff0_filter);
- mutex_init(&padapter->mutex_start);
return 0;