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authorJohan Hovold <johan@kernel.org>2021-04-07 12:39:24 +0200
committerJohan Hovold <johan@kernel.org>2021-04-08 09:46:03 +0200
commitc12860c0f6e6b6b0301760a2b0e3e6b3f83eace8 (patch)
treec3005d1fa404d7b918a9072883b936c7cfe9b2d3 /drivers/usb/serial/ftdi_sio.c
parentUSB: serial: ftdi_sio: ignore baud_base changes (diff)
downloadlinux-dev-c12860c0f6e6b6b0301760a2b0e3e6b3f83eace8.tar.xz
linux-dev-c12860c0f6e6b6b0301760a2b0e3e6b3f83eace8.zip
USB: serial: ftdi_sio: simplify TIOCGSERIAL permission check
Changing the deprecated custom_divisor field is an unprivileged operation so after verifying that flag field does not contain any privileged changes both updates can be carried out by any user. Combine the two branches and drop the erroneous comment. Note that private flags field is only used for ASYNC flags so there's no need to try to retain any other bits when updating the flags. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'drivers/usb/serial/ftdi_sio.c')
-rw-r--r--drivers/usb/serial/ftdi_sio.c13
1 files changed, 1 insertions, 12 deletions
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 3fd7875200b9..9228e56a91c0 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1496,27 +1496,16 @@ static int set_serial_info(struct tty_struct *tty,
mutex_lock(&priv->cfg_lock);
old_priv = *priv;
- /* Do error checking and permission checking */
-
if (!capable(CAP_SYS_ADMIN)) {
if ((ss->flags ^ priv->flags) & ~ASYNC_USR_MASK) {
mutex_unlock(&priv->cfg_lock);
return -EPERM;
}
- priv->flags = ((priv->flags & ~ASYNC_USR_MASK) |
- (ss->flags & ASYNC_USR_MASK));
- priv->custom_divisor = ss->custom_divisor;
- goto check_and_exit;
}
-
- /* Make the changes - these are privileged changes! */
-
- priv->flags = ((priv->flags & ~ASYNC_FLAGS) |
- (ss->flags & ASYNC_FLAGS));
+ priv->flags = ss->flags & ASYNC_FLAGS;
priv->custom_divisor = ss->custom_divisor;
-check_and_exit:
write_latency_timer(port);
if ((priv->flags ^ old_priv.flags) & ASYNC_SPD_MASK ||