Re: TTY: ntty, add one more sanity check

[Greg KH <greg@kroah.com>]

On Tue, Jun 07, 2011 at 07:30:31PM +0200, Jiri Slaby wrote:
> On 06/07/2011 07:20 PM, Greg KH wrote:
> > On Sun, Jun 05, 2011 at 02:16:17PM +0200, Jiri Slaby wrote:
> >> With the previous patch, we fixed another bug where read_buf was freed
> >> while we still was in n_tty_read. We currently check whether read_buf
> >> is NULL at the start of the function. Add one more check after we wake
> >> up from waiting for input.
> >>
> >> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
> >> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
> >> ---
> >>  drivers/tty/n_tty.c |    1 +
> >>  1 files changed, 1 insertions(+), 0 deletions(-)
> >>
> >> diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
> >> index 95d0a9c..c62c856 100644
> >> --- a/drivers/tty/n_tty.c
> >> +++ b/drivers/tty/n_tty.c
> >> @@ -1785,6 +1785,7 @@ do_it_again:
> >>  				break;
> >>  			}
> >>  			timeout = schedule_timeout(timeout);
> >> +			BUG_ON(!tty->read_buf);
> >>  			continue;
> >>  		}
> >>  		__set_current_state(TASK_RUNNING);
> > 
> > This doesn't apply anymore without some fuzz as stuff has changed in
> > this area in Linus's tree.
> > 
> > Can you refresh it and resend it so that I know it's correct?
> > 
> > Or, just verify that the diff below is correct, and I'll take that one.
> 
> Yes, it's correct.

Thanks for confirming, now applied.

greg k-h