[PATCH 2/2] staging: rtl8723bs: Fix two sleep-in-atomic-context bugs in _rtw_pwr_wakeup()

From: Jia-Ju Bai
Date: Fri Sep 14 2018 - 22:49:59 EST


The driver may sleep with holding a spinlock.
The function call paths (from bottom to top) in Linux-4.17 are:

[FUNC] msleep
drivers/staging/rtl8723bs/core/rtw_pwrctrl.c, 1243:
msleep in _rtw_pwr_wakeup
drivers/staging/rtl8723bs/core/rtw_ioctl_set.c, 510:
_rtw_pwr_wakeup in rtw_set_802_11_disassociate
drivers/staging/rtl8723bs/core/rtw_ioctl_set.c, 501:
spin_lock_bh in rtw_set_802_11_disassociate

[FUNC] msleep
drivers/staging/rtl8723bs/core/rtw_pwrctrl.c, 1255:
msleep in _rtw_pwr_wakeup
drivers/staging/rtl8723bs/core/rtw_ioctl_set.c, 510:
_rtw_pwr_wakeup in rtw_set_802_11_disassociate
drivers/staging/rtl8723bs/core/rtw_ioctl_set.c, 501:
spin_lock_bh in rtw_set_802_11_disassociate

To fix these bugs, msleep() is replaced with mdelay().

These bugs are found by my static analysis tool DSAC.

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
---
drivers/staging/rtl8723bs/core/rtw_pwrctrl.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_pwrctrl.c b/drivers/staging/rtl8723bs/core/rtw_pwrctrl.c
index 110bbe340b78..59a667753266 100644
--- a/drivers/staging/rtl8723bs/core/rtw_pwrctrl.c
+++ b/drivers/staging/rtl8723bs/core/rtw_pwrctrl.c
@@ -1232,7 +1232,7 @@ int _rtw_pwr_wakeup(struct adapter *padapter, u32 ips_deffer_ms, const char *cal
if (pwrpriv->ps_processing) {
DBG_871X("%s wait ps_processing...\n", __func__);
while (pwrpriv->ps_processing && jiffies_to_msecs(jiffies - start) <= 3000)
- msleep(10);
+ mdelay(10);
if (pwrpriv->ps_processing)
DBG_871X("%s wait ps_processing timeout\n", __func__);
else
@@ -1244,7 +1244,7 @@ int _rtw_pwr_wakeup(struct adapter *padapter, u32 ips_deffer_ms, const char *cal
while (pwrpriv->bInSuspend
&& jiffies_to_msecs(jiffies - start) <= 3000
) {
- msleep(10);
+ mdelay(10);
}
if (pwrpriv->bInSuspend)
DBG_871X("%s wait bInSuspend timeout\n", __func__);
--
2.17.0