From: Johan Hovold johan@kernel.org
[ Upstream commit 1b8b20868a6d64cfe8174a21b25b74367bdf0560 ]
Drivers should return -ENOTTY ("Inappropriate I/O control operation") when an ioctl isn't supported, while -EINVAL is used for invalid arguments.
Fix up the TIOCMGET, TIOCMSET and TIOCGICOUNT helpers which returned -EINVAL when a tty driver did not implement the corresponding operations.
Note that the TIOCMGET and TIOCMSET helpers predate git and do not get a corresponding Fixes tag below.
Fixes: d281da7ff6f7 ("tty: Make tiocgicount a handler") Signed-off-by: Johan Hovold johan@kernel.org Link: https://lore.kernel.org/r/20210407095208.31838-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/tty_io.c | 8 ++++---- include/linux/tty_driver.h | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index d7e56de19c58..ae3af8debf67 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -2424,14 +2424,14 @@ out: * @p: pointer to result * * Obtain the modem status bits from the tty driver if the feature - * is supported. Return -EINVAL if it is not available. + * is supported. Return -ENOTTY if it is not available. * * Locking: none (up to the driver) */
static int tty_tiocmget(struct tty_struct *tty, int __user *p) { - int retval = -EINVAL; + int retval = -ENOTTY;
if (tty->ops->tiocmget) { retval = tty->ops->tiocmget(tty); @@ -2449,7 +2449,7 @@ static int tty_tiocmget(struct tty_struct *tty, int __user *p) * @p: pointer to desired bits * * Set the modem status bits from the tty driver if the feature - * is supported. Return -EINVAL if it is not available. + * is supported. Return -ENOTTY if it is not available. * * Locking: none (up to the driver) */ @@ -2461,7 +2461,7 @@ static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd, unsigned int set, clear, val;
if (tty->ops->tiocmset == NULL) - return -EINVAL; + return -ENOTTY;
retval = get_user(val, p); if (retval) diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h index 31c2b5b166de..ebca9e4a2fed 100644 --- a/include/linux/tty_driver.h +++ b/include/linux/tty_driver.h @@ -236,7 +236,7 @@ * * Called when the device receives a TIOCGICOUNT ioctl. Passed a kernel * structure to complete. This method is optional and will only be called - * if provided (otherwise EINVAL will be returned). + * if provided (otherwise ENOTTY will be returned). */
#include <linux/export.h>