diff options
| author | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2023-07-10 02:26:45 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-07-20 19:21:16 +0200 |
| commit | 690c8b804ad2eafbd35da5d3c95ad325ca7d5061 (patch) | |
| tree | 8c6cec078caf83d111474b36550e9812d493e6c4 /drivers/tty/tty_io.c | |
| parent | fdf0eaf11452d72945af31804e2a1048ee1b574c (diff) | |
TIOCSTI: always enable for CAP_SYS_ADMIN
83efeeeb3d04 ("tty: Allow TIOCSTI to be disabled") broke BRLTTY's
ability to simulate keypresses on the console, thus effectively breaking
braille keyboards of blind users.
This restores the TIOCSTI feature for CAP_SYS_ADMIN processes, which
BRLTTY is, thus fixing braille keyboards without re-opening the security
issue.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Kees Cook <keescook@chromium.org>
Fixes: 83efeeeb3d04 ("tty: Allow TIOCSTI to be disabled")
Cc: stable@vger.kernel.org
Reported-by: Nicolas Pitre <nico@fluxnic.net>
Link: https://lore.kernel.org/r/20230710002645.v565c7xq5iddruse@begin
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/tty_io.c')
| -rw-r--r-- | drivers/tty/tty_io.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 3959efc717aa..63db04b9113a 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -2285,7 +2285,7 @@ static int tiocsti(struct tty_struct *tty, char __user *p) char ch, mbz = 0; struct tty_ldisc *ld; - if (!tty_legacy_tiocsti) + if (!tty_legacy_tiocsti && !capable(CAP_SYS_ADMIN)) return -EIO; if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) |