[PATCH] staging: rtl8188eu: Fix two sleep-in-atomic-context bugs in rtw_chk_hi_queue_cmd()

From: Jia-Ju Bai
Date: Sat Sep 01 2018 - 04:58:42 EST


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@xxxxxxxxx>
---
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