From c7f800ec9773d02a5b26faf77f829aa263226dc2 Mon Sep 17 00:00:00 2001
From: Jia-Ju Bai <baijiaju1990@gmail.com>
Date: Sat, 1 Sep 2018 16:58:29 +0800
Subject: [PATCH] staging: rtl8188eu: Fix two sleep-in-atomic-context bugs in rtw_chk_hi_queue_cmd()
Git-commit: c7f800ec9773d02a5b26faf77f829aa263226dc2
Patch-mainline: v4.20-rc1
References: FATE#326906

usb_write_port_complete() in usb_ops_linux.c is a completion handler
function for the USB driver. So it should not sleep, but it is can sleep
according to the function call paths (from bottom to top) in Linux-4.16:

[FUNC] kzalloc(GFP_KERNEL)
drivers/staging/rtl8188eu/core/rtw_cmd.c, 1081:
	kzalloc in rtw_chk_hi_queue_cmd
drivers/staging/rtl8188eu/os_dep/usb_ops_linux.c, 604:
	rtw_chk_hi_queue_cmd in usb_write_port_complete

[FUNC] kzalloc(GFP_KERNEL)
drivers/staging/rtl8188eu/core/rtw_cmd.c, 1075:
	kzalloc in rtw_chk_hi_queue_cmd
drivers/staging/rtl8188eu/os_dep/usb_ops_linux.c, 604:
	rtw_chk_hi_queue_cmd in usb_write_port_complete

To fix these bugs, GFP_KERNEL is replaced with GFP_ATOMIC.

These bugs are found by my static analysis tool DSAC.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/staging/rtl8188eu/core/rtw_cmd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/rtl8188eu/core/rtw_cmd.c b/drivers/staging/rtl8188eu/core/rtw_cmd.c
index 59039211dad2..7f9536c55774 100644
--- a/drivers/staging/rtl8188eu/core/rtw_cmd.c
+++ b/drivers/staging/rtl8188eu/core/rtw_cmd.c
@@ -1064,13 +1064,13 @@ u8 rtw_chk_hi_queue_cmd(struct adapter *padapter)
 	struct cmd_priv	*pcmdpriv = &padapter->cmdpriv;
 	u8	res = _SUCCESS;
 
-	ph2c = kzalloc(sizeof(struct cmd_obj), GFP_KERNEL);
+	ph2c = kzalloc(sizeof(struct cmd_obj), GFP_ATOMIC);
 	if (!ph2c) {
 		res = _FAIL;
 		goto exit;
 	}
 
-	pdrvextra_cmd_parm = kzalloc(sizeof(struct drvextra_cmd_parm), GFP_KERNEL);
+	pdrvextra_cmd_parm = kzalloc(sizeof(struct drvextra_cmd_parm), GFP_ATOMIC);
 	if (!pdrvextra_cmd_parm) {
 		kfree(ph2c);
 		res = _FAIL;
-- 
2.19.1