vt_compat_ioctl(): clean up, use compat_ptr() properly
authorAl Viro <viro@zeniv.linux.org.uk>
Wed, 12 Sep 2018 23:02:10 +0000 (19:02 -0400)
committerAl Viro <viro@zeniv.linux.org.uk>
Sat, 13 Oct 2018 04:50:50 +0000 (00:50 -0400)
we need it for "convert the structure" cases too

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
drivers/tty/vt/vt_ioctl.c

index a78ad10..82d38d7 100644 (file)
@@ -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);
 }