# Re: \[PATCH\] isdn: i4l: isdn\_tty: Fix some concurrency double-free bugs

- From: David Miller \<davem@davemloft.net\>
- Date: 2019-01-12 01:57:15 
- List: netdev
- Page: https://ratatoskr.run/netdev/2019/01/5482165
- Thread: https://ratatoskr.run/netdev/2019/01/5477393/t.md

```text
From: Jia-Ju Bai <redacted>
Date: Tue,  8 Jan 2019 21:04:48 +0800

> The functions isdn_tty_tiocmset() and isdn_tty_set_termios() may be
> concurrently executed.
 ...
> These possible bugs are found by a static tool written by myself and 
> my manual code review.
> 
> To fix these possible bugs, the mutex lock "modem_info_mutex" used in
> isdn_tty_tiocmset() is added in isdn_tty_set_termios().
> 
> Signed-off-by: Jia-Ju Bai <redacted>

Applied.
```