[PATCH 4/6] staging: rtl8192u: Replace GFP_ATOMIC with GFP_KERNEL in ieee80211_softmac_init

From: Jia-Ju Bai
Date: Tue Apr 10 2018 - 08:24:37 EST


ieee80211_softmac_init() is never called in atomic context.

The call chains ending up at ieee80211_softmac_init() is:
[1] ieee80211_softmac_init() <- alloc_ieee80211_rsl() <-
rtl8192_usb_probe()

rtl8192_usb_probe() is set as ".probe" in struct usb_driver.

Despite never getting called from atomic context,
ieee80211_softmac_init() calls kzalloc() with GFP_ATOMIC,
which does not sleep for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
which can sleep and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
---
drivers/staging/rtl8192u/ieee80211/ieee80211_softmac.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_softmac.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_softmac.c
index fe6f38b..cb4a2ad 100644
--- a/drivers/staging/rtl8192u/ieee80211/ieee80211_softmac.c
+++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_softmac.c
@@ -2682,7 +2682,7 @@ void ieee80211_softmac_init(struct ieee80211_device *ieee)
for(i = 0; i < 5; i++) {
ieee->seq_ctrl[i] = 0;
}
- ieee->pDot11dInfo = kzalloc(sizeof(RT_DOT11D_INFO), GFP_ATOMIC);
+ ieee->pDot11dInfo = kzalloc(sizeof(RT_DOT11D_INFO), GFP_KERNEL);
if (!ieee->pDot11dInfo)
IEEE80211_DEBUG(IEEE80211_DL_ERR, "can't alloc memory for DOT11D\n");
//added for AP roaming
--
1.9.1