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Don't allow opening the callout device when the callin device is already

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open (in disguise as the console device).  The only allowed combination
was supposed to be the callin device with the console.

Fix the assertion in ttydev_close() that was meant to detect this (it
only detected all 3 devices being open).  Assert this in ttydev_open()
too.

Submitted by:	bde
MFC after:	2 weeks
This commit is contained in:
Konstantin Belousov 2016-01-25 16:47:20 +00:00
parent 94241c6011
commit 2e77021e4c
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=294735
1 changed files with 6 additions and 3 deletions
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9
sys/kern/tty.c
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@ -263,10 +263,10 @@ ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
/*
* Make sure the "tty" and "cua" device cannot be opened at the
* same time.
* same time. The console is a "tty" device.
*/
if (TTY_CALLOUT(tp, dev)) {
if (tp->t_flags & TF_OPENED_IN) {
if (tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) {
error = EBUSY;
goto done;
}
@ -319,6 +319,8 @@ ttydev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
tp->t_flags |= TF_OPENED_OUT;
else
tp->t_flags |= TF_OPENED_IN;
MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
(tp->t_flags & TF_OPENED_OUT) == 0);
done: tp->t_flags &= ~TF_OPENCLOSE;
cv_broadcast(&tp->t_dcdwait);
@ -338,7 +340,8 @@ ttydev_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
* Don't actually close the device if it is being used as the
* console.
*/
MPASS((tp->t_flags & TF_OPENED) != TF_OPENED);
MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
(tp->t_flags & TF_OPENED_OUT) == 0);
if (dev == dev_console)
tp->t_flags &= ~TF_OPENED_CONS;
else