[PATCH 5.10 246/530] tty: fix return value for unsupported ioctls
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-05-12 15:56:57
Also in:
lkml
Subsystem:
the rest, tty layer and serial drivers · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
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 (local)
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 146bd6711562..bc5314092aa4 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c@@ -2492,14 +2492,14 @@ 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);
@@ -2517,7 +2517,7 @@ 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) */
@@ -2529,7 +2529,7 @@ 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 358446247ccd..7186d77f431e 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>
--
2.30.2