| Message ID | 20210408131602.27956-3-johan@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,1/3] Revert "USB: cdc-acm: fix rounding error in TIOCSSERIAL" | expand |
Am Donnerstag, den 08.04.2021, 15:16 +0200 schrieb Johan Hovold: > TIOCSSERIAL is a horrid, underspecified, legacy interface which for most > serial devices is only useful for setting the close_delay and > closing_wait parameters. > > A non-privileged user has only ever been able to set the since long > deprecated ASYNC_SPD flags and trying to change any other *supported* > feature should result in -EPERM being returned. Setting the current > values for any supported features should return success. > > Fix the cdc-acm implementation which instead indicated that the > TIOCSSERIAL ioctl was not even implemented when a non-privileged user > set the current values. > > Fixes: ba2d8ce9db0a ("cdc-acm: implement TIOCSSERIAL to avoid blocking close(2)") > Signed-off-by: Johan Hovold <johan@kernel.org> Acked-by: Oliver Neukum <oneukum@suse.com>
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 96e221803fa6..43e31dad4831 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -955,8 +955,6 @@ static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss) if ((close_delay != acm->port.close_delay) || (closing_wait != acm->port.closing_wait)) retval = -EPERM; - else - retval = -EOPNOTSUPP; } else { acm->port.close_delay = close_delay; acm->port.closing_wait = closing_wait;
TIOCSSERIAL is a horrid, underspecified, legacy interface which for most serial devices is only useful for setting the close_delay and closing_wait parameters. A non-privileged user has only ever been able to set the since long deprecated ASYNC_SPD flags and trying to change any other *supported* feature should result in -EPERM being returned. Setting the current values for any supported features should return success. Fix the cdc-acm implementation which instead indicated that the TIOCSSERIAL ioctl was not even implemented when a non-privileged user set the current values. Fixes: ba2d8ce9db0a ("cdc-acm: implement TIOCSSERIAL to avoid blocking close(2)") Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/usb/class/cdc-acm.c | 2 -- 1 file changed, 2 deletions(-)