Commit 62d65bdd authored Mar 27, 2020 by Matthias Reichl Committed by Greg Kroah-Hartman Mar 27, 2020

USB: cdc-acm: restore capability check order



commit b401f8c4 ("USB: cdc-acm: fix rounding error in TIOCSSERIAL")
introduced a regression by changing the order of capability and close
settings change checks. When running with CAP_SYS_ADMIN setting the
close settings to the values already set resulted in -EOPNOTSUPP.

Fix this by changing the check order back to how it was before.

Fixes: b401f8c4 ("USB: cdc-acm: fix rounding error in TIOCSSERIAL")
Cc: Anthony Mallet <anthony.mallet@laas.fr>
Cc: stable <stable@vger.kernel.org>
Cc: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Matthias Reichl <hias@horus.com>
Link: https://lore.kernel.org/r/20200327150350.3657-1-hias@horus.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 70d8b9e5

drivers/usb/class/cdc-acm.c

+9 −9

Original line number	Diff line number	Diff line
		@@ -923,16 +923,16 @@ static int set_serial_info(struct tty_struct tty, struct serial_struct ss)

		mutex_lock(&acm->port.mutex);

		if (!capable(CAP_SYS_ADMIN)) {
		if ((ss->close_delay != old_close_delay) \|\|
		(ss->closing_wait != old_closing_wait)) {
		if (!capable(CAP_SYS_ADMIN))
		(ss->closing_wait != old_closing_wait))
		retval = -EPERM;
		else {
		else
		retval = -EOPNOTSUPP;
		} else {
		acm->port.close_delay = close_delay;
		acm->port.closing_wait = closing_wait;
		}
		} else
		retval = -EOPNOTSUPP;

		mutex_unlock(&acm->port.mutex);
		return retval;

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