VT_RESIZEX: get rid of field-by-field copyin

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2017-09-29 12:34:13 -04:00
parent 7d5cb45655
commit 1b3bce4d6b

View File

@ -842,58 +842,44 @@ 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;