drm/vmwgfx: Don't double-free the mode stored in par->set_mode

commit c2d3115538 upstream.

When calling vmw_fb_set_par(), the mode stored in par->set_mode gets free'd
twice. The first free is in vmw_fb_kms_detach(), the second is near the
end of vmw_fb_set_par() under the name of 'old_mode'. The mode-setting code
only works correctly if the mode doesn't actually change. Removing
'old_mode' in favor of using par->set_mode directly fixes the problem.

Cc: <stable@vger.kernel.org>
Fixes: a278724aa2 ("drm/vmwgfx: Implement fbdev on kms v2")
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Deepak Rawat <drawat@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Thomas Zimmermann 2019-03-18 15:47:58 +01:00 committed by Greg Kroah-Hartman
parent c179e6deb2
commit eea23ca21b
1 changed files with 3 additions and 9 deletions

View File

@ -531,11 +531,9 @@ static int vmw_fb_set_par(struct fb_info *info)
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PVSYNC)
};
struct drm_display_mode *old_mode;
struct drm_display_mode *mode;
int ret;
old_mode = par->set_mode;
mode = drm_mode_duplicate(vmw_priv->dev, &new_mode);
if (!mode) {
DRM_ERROR("Could not create new fb mode.\n");
@ -546,11 +544,7 @@ static int vmw_fb_set_par(struct fb_info *info)
mode->vdisplay = var->yres;
vmw_guess_mode_timing(mode);
if (old_mode && drm_mode_equal(old_mode, mode)) {
drm_mode_destroy(vmw_priv->dev, mode);
mode = old_mode;
old_mode = NULL;
} else if (!vmw_kms_validate_mode_vram(vmw_priv,
if (!vmw_kms_validate_mode_vram(vmw_priv,
mode->hdisplay *
DIV_ROUND_UP(var->bits_per_pixel, 8),
mode->vdisplay)) {
@ -613,8 +607,8 @@ static int vmw_fb_set_par(struct fb_info *info)
schedule_delayed_work(&par->local_work, 0);
out_unlock:
if (old_mode)
drm_mode_destroy(vmw_priv->dev, old_mode);
if (par->set_mode)
drm_mode_destroy(vmw_priv->dev, par->set_mode);
par->set_mode = mode;
drm_modeset_unlock_all(vmw_priv->dev);