Bluetooth: Fix a possible sleep-in-atomic bug in bluecard_write_wakeup
authorJia-Ju Bai <baijiaju1990@gmail.com>
Wed, 13 Dec 2017 09:28:04 +0000 (17:28 +0800)
committerMarcel Holtmann <marcel@holtmann.org>
Wed, 13 Dec 2017 13:38:59 +0000 (14:38 +0100)
The driver may sleep in the interrupt handler.
The function call path is:
bluecard_interrupt (interrupt handler)
  bluecard_write_wakeup
    schedule_timeout --> may sleep

To fix it, schedule_timeout is replaced with mdelay.

This bug is found by my static analysis tool(DSAC) and checked by my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
drivers/bluetooth/bluecard_cs.c

index d513ef4..82437a6 100644 (file)
@@ -302,9 +302,7 @@ static void bluecard_write_wakeup(struct bluecard_info *info)
                        }
 
                        /* Wait until the command reaches the baseband */
-                       prepare_to_wait(&wq, &wait, TASK_INTERRUPTIBLE);
-                       schedule_timeout(HZ/10);
-                       finish_wait(&wq, &wait);
+                       mdelay(100);
 
                        /* Set baud on baseband */
                        info->ctrl_reg &= ~0x03;
@@ -316,9 +314,7 @@ static void bluecard_write_wakeup(struct bluecard_info *info)
                        outb(info->ctrl_reg, iobase + REG_CONTROL);
 
                        /* Wait before the next HCI packet can be send */
-                       prepare_to_wait(&wq, &wait, TASK_INTERRUPTIBLE);
-                       schedule_timeout(HZ);
-                       finish_wait(&wq, &wait);
+                       mdelay(1000);
                }
 
                if (len == skb->len) {