Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Jia-Ju Bai <baijiaju1990@gmail.com>
To:     gregkh@linuxfoundation.org, jananis37@gmail.com
Cc:     devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org,
        Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [PATCH] staging: rtl8188eu: Fix two sleep-in-atomic-context bugs in rtw_chk_hi_queue_cmd()
Date:   Sat,  1 Sep 2018 16:58:29 +0800
Message-Id: <20180901085829.8246-1-baijiaju1990@gmail.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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>
---
 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 72099f5d6915..526baa699a57 100644
--- a/drivers/staging/rtl8188eu/core/rtw_cmd.c
+++ b/drivers/staging/rtl8188eu/core/rtw_cmd.c
@@ -1072,13 +1072,13 @@ 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;
-- 
2.17.0