From ac5e4875e6d81f7f24a70247770c32585d773839 Mon Sep 17 00:00:00 2001 From: Jia-Ju Bai Date: Wed, 20 Jun 2018 10:58:01 +0800 Subject: [PATCH] staging: rtlwifi: Fix a possible sleep-in-atomic-context bug in _is_fw_read_cmd_down() The driver may sleep with holding a spinlock. The function call path (from bottom to top) in Linux-4.16.7 is: [FUNC] schedule drivers/staging/rtlwifi/halmac/rtl_halmac.c, 884: schedule in _is_fw_read_cmd_down drivers/staging/rtlwifi/halmac/rtl_halmac.c, 912: _is_fw_read_cmd_down in rtl_halmac_send_h2c drivers/staging/rtlwifi/halmac/rtl_halmac.c, 907: _raw_spin_lock_irqsave in rtl_halmac_send_h2c To fix this bug, schedule() is replaced with mdelay(1). This bug is found by my static analysis tool (DSAC-2) and checked by my code review. Signed-off-by: Jia-Ju Bai Signed-off-by: Greg Kroah-Hartman --- drivers/staging/rtlwifi/halmac/rtl_halmac.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/staging/rtlwifi/halmac/rtl_halmac.c b/drivers/staging/rtlwifi/halmac/rtl_halmac.c index ae433aa6ebbb..f0c6fc8c6aca 100644 --- a/drivers/staging/rtlwifi/halmac/rtl_halmac.c +++ b/drivers/staging/rtlwifi/halmac/rtl_halmac.c @@ -870,7 +870,7 @@ static bool _is_fw_read_cmd_down(struct rtl_priv *rtlpriv, u8 msgbox_num) if (valid == 0) read_down = true; else - schedule(); + mdelay(1); } while ((!read_down) && (retry_cnts--)); return read_down;