VT_RESIZEX: get rid of field-by-field copyin

[ Upstream commit 1b3bce4d6bf839304a90951b4b25a5863533bf2a ]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c
index 638eb9b..d4c1b10 100644 (file)
--- a/drivers/tty/vt/vt_ioctl.c
+++ b/drivers/tty/vt/vt_ioctl.c
@@ -850,58 +850,44 @@ int vt_ioctl(struct tty_struct *tty,
 
        case VT_RESIZEX:
        {
-               struct vt_consize __user *vtconsize = up;
-               ushort ll,cc,vlin,clin,vcol,ccol;
+               struct vt_consize v;
                if (!perm)
                        return -EPERM;
-               if (!access_ok(VERIFY_READ, vtconsize,
-                               sizeof(struct vt_consize))) {
-                       ret = -EFAULT;
-                       break;
-               }
+               if (copy_from_user(&v, up, sizeof(struct vt_consize)))
+                       return -EFAULT;
                /* FIXME: Should check the copies properly */
-               __get_user(ll, &vtconsize->v_rows);
-               __get_user(cc, &vtconsize->v_cols);
-               __get_user(vlin, &vtconsize->v_vlin);
-               __get_user(clin, &vtconsize->v_clin);
-               __get_user(vcol, &vtconsize->v_vcol);
-               __get_user(ccol, &vtconsize->v_ccol);
-               vlin = vlin ? vlin : vc->vc_scan_lines;
-               if (clin) {
-                       if (ll) {
-                               if (ll != vlin/clin) {
-                                       /* Parameters don't add up */
-                                       ret = -EINVAL;
-                                       break;
-                               }
-                       } else 
-                               ll = vlin/clin;
+               if (!v.v_vlin)
+                       v.v_vlin = vc->vc_scan_lines;
+               if (v.v_clin) {
+                       int rows = v.v_vlin/v.v_clin;
+                       if (v.v_rows != rows) {
+                               if (v.v_rows) /* Parameters don't add up */
+                                       return -EINVAL;
+                               v.v_rows = rows;
+                       }
                }
-               if (vcol && ccol) {
-                       if (cc) {
-                               if (cc != vcol/ccol) {
-                                       ret = -EINVAL;
-                                       break;
-                               }
-                       } else
-                               cc = vcol/ccol;
+               if (v.v_vcol && v.v_ccol) {
+                       int cols = v.v_vcol/v.v_ccol;
+                       if (v.v_cols != cols) {
+                               if (v.v_cols)
+                                       return -EINVAL;
+                               v.v_cols = cols;
+                       }
                }
 
-               if (clin > 32) {
-                       ret =  -EINVAL;
-                       break;
-               }
-                   
+               if (v.v_clin > 32)
+                       return -EINVAL;
+
                for (i = 0; i < MAX_NR_CONSOLES; i++) {
                        if (!vc_cons[i].d)
                                continue;
                        console_lock();
-                       if (vlin)
-                               vc_cons[i].d->vc_scan_lines = vlin;
-                       if (clin)
-                               vc_cons[i].d->vc_font.height = clin;
+                       if (v.v_vlin)
+                               vc_cons[i].d->vc_scan_lines = v.v_vlin;
+                       if (v.v_clin)
+                               vc_cons[i].d->vc_font.height = v.v_clin;
                        vc_cons[i].d->vc_resize_user = 1;
-                       vc_resize(vc_cons[i].d, cc, ll);
+                       vc_resize(vc_cons[i].d, v.v_cols, v.v_rows);
                        console_unlock();
                }
                break;