From a626c4fddd784a76b06573165f44b6bbba2d1808 Mon Sep 17 00:00:00 2001 From: Jia-Ju Bai Date: Tue, 10 Apr 2018 20:23:54 +0800 Subject: [PATCH] staging: rtl8192u: Replace GFP_ATOMIC with GFP_KERNEL in prism2_wep_init prism2_wep_init() is never called in atomic context. prism2_wep_init() is only set as ".init" in struct ieee80211_crypto_ops. The call chains ending up at "->init" function are: [1] ->init() <- ieee80211_wpa_set_encryption() <- ieee80211_wpa_supplicant_ioctl() [2] ->init() <- ieee80211_wx_set_encode_ext_rsl() <- r8192_wx_set_enc_ext() [3] ->init() <- ieee80211_wx_set_encode_rsl() <- r8192_wx_set_enc() ieee80211_wpa_supplicant_ioctl(), r8192_wx_set_enc_ext() and r8192_wx_set_enc() call mutex_lock(), which indicates these functions are not called in atomic context. Despite never getting called from atomic context, prism2_wep_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 Signed-off-by: Greg Kroah-Hartman --- drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c index 7ba4b07aa842..b9f86be9e52b 100644 --- a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c +++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_wep.c @@ -41,7 +41,7 @@ static void *prism2_wep_init(int keyidx) { struct prism2_wep_data *priv; - priv = kzalloc(sizeof(*priv), GFP_ATOMIC); + priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return NULL; priv->key_idx = keyidx; -- 2.30.2