[ldv-project] [net] rtl8188ee: a potential race condition

Pavel Andrianov
2016-06-10T09:25:26Z

Hi!

There is a potential data race in
drivers/net/wireless/realtek/rtlwifi/rtl8188ee/rtl8188ee.ko.

In the function rtl88ee_gpio_radio_on_off_checking the flag
ppsc->rfchange_inprogress is set with a spinlock protection. In the
function rtl_ps_set_rf_state the flag is read also under a spinlock. But
the function rtl88e_dm_watchdog read it without any locks. As a result
rtl88e_dm_watchdog may execute the succeeding code while changing (with
the flag rfchange_inprogress == true). I do not exactly determine the
consequences, but likely they are not good if there exists such check.
Could anybody more confident confirm this?

The function rtl_ps_set_rf_state is always called with its parameter
[protect_or_not == false]. Is this flag really necessary, if the value
'true' is never used? The function is also set the flag
ppsc->rfchange_inprogress and may affect the rtl88e_dm_watchdog as in
the previous case.

--
Pavel Andrianov
Linux Verification Center, ISPRAS
web: http://linuxtesting.org
e-mail: andrianov@ispras.ru