tty: Add sysctl knob to globally disable TIOCSTI

Reviewed by:	markj
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D57233

This commit is contained in:

Ed Maste

2026-05-25 09:59:40 -04:00

parent 13fb6dbc73

commit c289291a67

1 changed files with 8 additions and 0 deletions

									
										sys/kern/tty.c
									
		+8
		
												View File
												
				@@ -101,6 +101,10 @@ static int  tty_drainwait = 5 * 60;

				SYSCTL_INT(_kern, OID_AUTO, tty_drainwait, CTLFLAG_RWTUN,

				    &tty_drainwait, 0, "Default output drain timeout in seconds");

				static bool tty_tiocsti = true;

				SYSCTL_BOOL(_security_bsd, OID_AUTO, tiocsti, CTLFLAG_RWTUN,

				    &tty_tiocsti, 0, "Allow TIOCSTI ioctl");

				/*

				 * Set TTY buffer sizes.

				 */

				@@ -1651,6 +1655,10 @@ tty_set_winsize(struct tty *tp, const struct winsize *wsz)

				static int

				tty_sti_check(struct tty *tp, int fflag, struct thread *td)

				{

					/* Check for global disable. */

					if (!tty_tiocsti)

						return (EPERM);

					/* Root can bypass all of our constraints. */

					if (priv_check(td, PRIV_TTY_STI) == 0)

						return (0);