[PATCH 46/50] vt_compat_ioctl(): clean up, use compat_ptr() properly

From: Al Viro
Date: Wed Sep 12 2018 - 22:41:21 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

we need it for "convert the structure" cases too

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
drivers/tty/vt/vt_ioctl.c | 31 +++++++++----------------------
1 file changed, 9 insertions(+), 22 deletions(-)

diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c
index a78ad10a119b..82d38d7ba014 100644
--- a/drivers/tty/vt/vt_ioctl.c
+++ b/drivers/tty/vt/vt_ioctl.c
@@ -1171,17 +1171,13 @@ long vt_compat_ioctl(struct tty_struct *tty,
{
struct vc_data *vc = tty->driver_data;
struct console_font_op op; /* used in multiple places here */
- unsigned int console;
- void __user *up = (void __user *)arg;
+ unsigned int console = vc->vc_num;
+ void __user *up = compat_ptr(arg);
int perm;
- int ret = 0;

- console = vc->vc_num;

- if (!vc_cons_allocated(console)) { /* impossible? */
- ret = -ENOIOCTLCMD;
- goto out;
- }
+ if (!vc_cons_allocated(console)) /* impossible? */
+ return -ENOIOCTLCMD;

/*
* To have permissions to do most of the vt ioctls, we either have
@@ -1197,17 +1193,14 @@ long vt_compat_ioctl(struct tty_struct *tty,
*/
case PIO_FONTX:
case GIO_FONTX:
- ret = compat_fontx_ioctl(cmd, up, perm, &op);
- break;
+ return compat_fontx_ioctl(cmd, up, perm, &op);

case KDFONTOP:
- ret = compat_kdfontop_ioctl(up, perm, &op, vc);
- break;
+ return compat_kdfontop_ioctl(up, perm, &op, vc);

case PIO_UNIMAP:
case GIO_UNIMAP:
- ret = compat_unimap_ioctl(cmd, up, perm, vc);
- break;
+ return compat_unimap_ioctl(cmd, up, perm, vc);

/*
* all these treat 'arg' as an integer
@@ -1232,21 +1225,15 @@ long vt_compat_ioctl(struct tty_struct *tty,
case VT_DISALLOCATE:
case VT_RESIZE:
case VT_RESIZEX:
- goto fallback;
+ return vt_ioctl(tty, cmd, arg);

/*
* the rest has a compatible data structure behind arg,
* but we have to convert it to a proper 64 bit pointer.
*/
default:
- arg = (unsigned long)compat_ptr(arg);
- goto fallback;
+ return vt_ioctl(tty, cmd, (unsigned long)up);
}
-out:
- return ret;
-
-fallback:
- return vt_ioctl(tty, cmd, arg);
}


--
2.11.0